Database: MEDLINE <1966 to May Week 4 2002>
Search Strategy: (free weights vs machines)
------------------------------------------------------------------------------1
free weight$.af. (177)
2
(machine$ or mechanical).af. (120314)
3
1 and 2 (12)
4
open chain.af. (281)
5
close$ chain.af. (58)
6
exercise$.af. (116497)
7
1 and 2 and 3 (12)
8
3 or 7 (12)
9
(1 or 2) and 6 (2523)
10
1 and 6 (74)
11
limit 10 to review (4)
12
limit 10 to yr=2000-2002 (19)
13
8 or 11 or 12 (27)
14
(4 or 5) and 6 (28)
15
13 or 14 (55)
16
limit 15 to english language (53)
17
from 16 keep 1-53 (53)
18
from 17 keep 1-53 (53)
***************************
<1>
Unique Identifier
11541605
Medline Identifier
99601818
Authors
Berg HE. Tesch PA.
Institution
Department of Physiology and Pharmacology, Karolinska Institute,
Stockholm, Sweden.
Title
Force and power characteristics of a resistive exercise device for use
in space.
Source
Acta Astronautica. 42(1-8):219-30, 1998 Jan-Apr.
Abstract
We have developed a non-gravity dependent mechanical device, which
provides resistance during coupled concentric and eccentric muscle
actions, through the inertia of a spinning fly-wheel (Fly-Wheel
Ergometry; FWE). Our research shows that lower-limb FWE exercise can
produce forces and thus muscular stress comparable to what is typical of
advanced resistance training using free weights. FWE also offers greater
training stimuli during eccentric relative to concentric muscle actions,
as evidenced by force and electromyographic (EMG) measurements. Muscle
use of specific muscle groups, as assessed by the exercise-induced
contrast shift of magnetic resonance images, is similar during lower-limb
FWE and the barbell squat. Unlike free-weight exercise, FWE allows for
maximal voluntary effort in each repetition of an exercise bout.
Likewise, FWE exercise, not unassisted free-weight exercise, produces
eccentric "overload". Collectively, the inherent features of this
resistive exercise device and the results of the physiological
evaluations we have performed, suggest that resistance exercise using FWE
could be used as an effective exercise counter-measure in space. The
flywheel principle can be employed to any exercise configuration and
designed into a compact device allowing for exercises stressing those
muscles and bone structures, which are thought to be most affected by
long-duration spaceflight.
<2>
Unique Identifier
8526273
Medline Identifier
96089267
Authors
Shelbourne KD. Klootwyk TE. Wilckens JH. De Carlo MS.
Institution
Methodist Sports Medicine Center, Indianapolis, Indiana, USA.
Title
Ligament stability two to six years after anterior cruciate ligament
reconstruction with autogenous patellar tendon graft and participation in
accelerated rehabilitation program.
Source
American Journal of Sports Medicine. 23(5):575-9, 1995 Sep-Oct.
Abstract
We studied patients who participated in our accelerated rehabilitation
program after anterior cruciate ligament reconstructive surgery to
determine if they showed signs of patellar tendon graft stretching. This
program initiated in 1987 emphasizes early full hyperextension, early
weightbearing as tolerated, and closed-chain functional activities with
rapid return to sports when the patient has attained full range of
motion, approximately 65% of strength, and has accomplished the running
and agility drills prescribed. A total of 209 patients met the criteria
of KT-1000 arthrometer followup at the time full range of motion (5
degrees/0 degrees/135 degrees) was attained and at 2 years or more after
surgery. The KT-1000 arthrometer manual maximum difference between the
reconstructed and normal knees was used as the indicator of change in the
graft length. All patients completed postoperative subjective
questionnaires. The mean KT-1000 arthrometer value was 2.06 mm (SD, +/2.2) at full range of motion and 2.10 mm (SD, +/- 1.9) at more than 2
years of followup (P = 0.7961). The patients' subjective stability scores
averaged 19.6 with 97% reporting no instability episodes. Based on our
findings, we conclude that an accelerated rehabilitation program after
this type of reconstruction does not affect long-term stability as
measured by the KT-1000 arthrometer.
<3>
Unique Identifier
8037271
Medline Identifier
94311385
Authors
Rubinstein RA Jr. Shelbourne KD. VanMeter CD. McCarroll JC. Rettig
AC.
Institution
Methodist Sports Medicine Center, Indianapolis, Indiana 46202.
Title
Isolated autogenous bone-patellar tendon-bone graft site morbidity.
Source
American Journal of Sports Medicine. 22(3):324-7, 1994 May-Jun.
Abstract
To distinguish between morbidity caused by the isolated patellar tendon
graft harvest and morbidity associated with anterior cruciate ligament
reconstruction when the graft is harvested from the involved knee, we
studied 20 patients who had an isolated contralateral graft harvest for
anterior cruciate ligament reconstruction in the opposite knee. We
defined and quantitated the morbidity by evaluating the uninjured knee
from preoperative studies to current followup (range, 0.5 to 5 years;
average, 2 years). All graft harvest surgeries were performed in an
identical fashion. Rehabilitation of the harvest knee included immediate
range of motion, weightbearing, and closed chain kinetic exercises with a
emphasis on early strengthening. All patients regained full knee range of
motion by 3 weeks. At final followup, there was no clinical or
radiographic evidence of patella contracture or baja. Quadriceps strength
averaged 69% at 6 weeks and returned to 93% at 1 year and 95% at 2 years.
Activity-related soreness at the donor site (patellar tendinitis) was
rarely restricting and resolved after the 1st year. No patient complained
of patellofemoral joint pain in the donor knee. The modified Noyes
subjective questionnaire score averaged 97 of 100 at last followup. The
morbidity of an isolated autogenous patellar tendon graft harvest appears
to be of short duration and largely reversible.
<4>
Unique Identifier
8638746
Medline Identifier
96203385
Authors
Rennison M.
Title
Open versus closed chain kinetic exercises after anterior cruciate
ligament reconstruction. A prospective randomized study. [letter;
comment.].
Comments
Comment on: Am J Sports Med. 1995 Jul-Aug;23(4):401-6 ; 7573647
Source
American Journal of Sports Medicine. 24(1):125, 1996 Jan-Feb.
<5>
Unique Identifier
11032216
Medline Identifier
20484955
Authors
Kraemer WJ. Ratamess N. Fry AC. Triplett-McBride T. Koziris LP.
Bauer JA. Lynch JM. Fleck SJ.
Institution
The Human Performance Laboratory, Ball State University, Muncie,
Indiana 47306, USA.
Title
Influence of resistance training volume and periodization on
physiological and performance adaptations in collegiate women tennis
players.
Source
American Journal of Sports Medicine. 28(5):626-33, 2000 Sep-Oct.
Abstract
Few data exist on the long-term adaptations to heavy resistance
training in women. The purpose of this investigation was to examine the
effect of volume of resistance exercise on the development of physical
performance abilities in competitive, collegiate women tennis players.
Twenty-four tennis players were matched for tennis ability and randomly
placed into one of three groups: a no resistance exercise control group,
a periodized multiple-set resistance training group, or a single-set
circuit resistance training group. No significant changes in body mass
were observed in any of the groups throughout the entire training period.
However, significant increases in fat-free mass and decreases in percent
body fat were observed in the periodized training group after 4, 6, and 9
months of training. A significant increase in power output was observed
after 9 months of training in the periodized training group only. Onerepetition maximum strength for the bench press, free-weight shoulder
press, and leg press increased significantly after 4, 6, and 9 months of
training in the periodized training group, whereas the single-set circuit
group increased only after 4 months of training. Significant increases in
serve velocity were observed after 4 and 9 months of training in the
periodized training group, whereas no significant changes were observed
in the single-set circuit group. These data demonstrate that sportspecific resistance training using a periodized multiple-set training
method is superior to low-volume single-set resistance exercise protocols
in the development of physical abilities in competitive, collegiate women
tennis players.
<6>
Unique Identifier
11032216
Medline Identifier
20484955
Authors
Kraemer WJ. Ratamess N. Fry AC. Triplett-McBride T. Koziris LP.
Bauer JA. Lynch JM. Fleck SJ.
Institution
The Human Performance Laboratory, Ball State University, Muncie,
Indiana 47306, USA.
Title
Influence of resistance training volume and periodization on
physiological and performance adaptations in collegiate women tennis
players.
Source
American Journal of Sports Medicine. 28(5):626-33, 2000 Sep-Oct.
Abstract
Few data exist on the long-term adaptations to heavy resistance
training in women. The purpose of this investigation was to examine the
effect of volume of resistance exercise on the development of physical
performance abilities in competitive, collegiate women tennis players.
Twenty-four tennis players were matched for tennis ability and randomly
placed into one of three groups: a no resistance exercise control group,
a periodized multiple-set resistance training group, or a single-set
circuit resistance training group. No significant changes in body mass
were observed in any of the groups throughout the entire training period.
However, significant increases in fat-free mass and decreases in percent
body fat were observed in the periodized training group after 4, 6, and 9
months of training. A significant increase in power output was observed
after 9 months of training in the periodized training group only. Onerepetition maximum strength for the bench press, free-weight shoulder
press, and leg press increased significantly after 4, 6, and 9 months of
training in the periodized training group, whereas the single-set circuit
group increased only after 4 months of training. Significant increases in
serve velocity were observed after 4 and 9 months of training in the
periodized training group, whereas no significant changes were observed
in the single-set circuit group. These data demonstrate that sportspecific resistance training using a periodized multiple-set training
method is superior to low-volume single-set resistance exercise protocols
in the development of physical abilities in competitive, collegiate women
tennis players.
<7>
Unique Identifier
11476390
Medline Identifier
21368628
Authors
Cohen ZA. Roglic H. Grelsamer RP. Henry JH. Levine WN. Mow VC.
Ateshian GA.
Institution
Department of Mechanical Engineering, Columbia University, New York,
New York 10032, USA.
Title
Patellofemoral stresses during open and closed kinetic chain exercises.
An analysis using computer simulation.
Source
American Journal of Sports Medicine. 29(4):480-7, 2001 Jul-Aug.
Abstract
Rehabilitation of the symptomatic patellofemoral joint aims to
strengthen the quadriceps muscles while limiting stresses on the
articular cartilage. Some investigators have advocated closed kinetic
chain exercises, such as squats, because open kinetic chain exercises,
such as leg extensions, have been suspected of placing supraphysiologic
stresses on patellofemoral cartilage. We performed computer simulations
on geometric data from five cadaveric knees to compare three types of
open kinetic chain leg extension exercises (no external load on the
ankle, 25-N ankle load, and 100-N ankle load) with closed kinetic chain
knee-bend exercises in the range of 20 degrees to 90 degrees of flexion.
The exercises were compared in terms of the quadriceps muscle forces,
patellofemoral joint contact forces and stresses, and "benefit indices"
(the ratio of the quadriceps muscle force to the contact stress). The
study revealed that, throughout the entire flexion range, the open
kinetic chain stresses were not supraphysiologic nor significantly higher
than the closed kinetic chain exercise stresses. These findings are
important for patients who have undergone an operation and may feel too
unstable on their feet to do closed chain kinetic chain exercises. Open
kinetic chain exercises at low flexion angles are also recommended for
patients whose proximal patellar lesions preclude loading the
patellofemoral joint in deeper flexion.
<8>
Unique Identifier
7573647
Medline Identifier
96040427
Authors
Bynum EB. Barrack RL. Alexander AH.
Institution
Department of Orthopaedic Surgery, Naval Medical Center, Oakland, CA
94627-2260, USA.
Title
Open versus closed chain kinetic exercises after anterior cruciate
ligament reconstruction. A prospective randomized study. [see comments.].
Comments
Comment in: Am J Sports Med. 1996 Jan-Feb;24(1):125 ; 8638746
Source
American Journal of Sports Medicine. 23(4):401-6, 1995 Jul-Aug.
Abstract
We conducted a prospective, randomized study of open and closed kinetic
chain exercises during accelerated rehabilitation after anterior cruciate
ligament reconstruction to determine if closed kinetic chain exercises
are safe and if they offer any advantages over conventional
rehabilitation. The closed kinetic chain group used a length of elastic
tubing, the Sport Cord, to perform weightbearing exercises and the open
kinetic chain group used conventional physical therapy equipment. Results
are reported with a minimum 1-year followup (mean, 19 months). Pre- and
postoperative evaluation included the Lysholm knee function scoring
scale, Tegner activity rating scale and KT-1000 arthrometer measurements.
Overall, stability was restored in over 90% of the knees. Preoperative
patellofemoral pain was reduced significantly; 95% of the patients had a
full range of motion. The closed kinetic chain group had lower mean KT1000 arthrometer side-to-side differences, less patellofemoral pain, was
generally more satisfied with the end result, and more often thought they
returned to normal daily activities and sports sooner than expected. We
concluded that closed kinetic chain exercises are safe and effective and
offer some important advantages over open kinetic chain exercises. As a
result of this study, we now use the closed kinetic chain protocol
exclusively after anterior cruciate ligament reconstruction.
<9>
Unique Identifier
11932855
Medline Identifier
21929322
Authors
Rossi MD. Brown LE. Whitehurst M. Charni C. Hankins J. Taylor CL.
Institution
Department of Exercise Science and Health, Florida Atlantic University,
2912 College Ave., Davie, FL 33314, USA. mark.rossi@eudoramail.com
Title
Comparison of knee extensor strength between limbs in individuals with
bilateral total knee replacement.
Source
Archives of Physical Medicine & Rehabilitation. 83(4):523-6, 2002 Apr.
Abstract
OBJECTIVES: To determine and compare force production of the knee
extensors between limbs after bilateral total knee arthroplasty (TKA).
DESIGN: Two repeated-measures designs (2 factors: limb, time) assessing
for differences in strength between limbs over 3 times at 2 different
testing speeds. SETTING: Private and institutional practice.
PARTICIPANTS: Fourteen volunteers (6 men, 8 women; mean age +/- standard
deviation, 74.57 +/- 5.5 y; height, 169.91 +/- 9.43 cm; weight, 76.42 +/9.85 kg) with bilateral TKA. Open-chain knee extensor strength was
measured in both legs before surgery and 30 and 60 days after TKA at 60
degrees /s and 180 degrees /s. INTERVENTION: Rehabilitation 3 times
weekly for 8 weeks. Treatment consisted of gait, transfer training,
stationary cycle work, and a progressive resistance-training program.
MAIN OUTCOME MEASURE: Peak torque measured isokinetically. RESULTS: Limb
by time interaction was not significant for either 60 degrees /s (F(2,26)
=.75, P =.351) or 180 degrees /s (F(2,26) =.78, P =.393). A significant
main effect of time was found at 60 degrees /s (F(2,26) = 14.22, P
=.0001) and 180 degrees /s (F(2,26) = 10.47, P =.003). CONCLUSIONS:
During the first month after TKA, bilateral knee extensor forceproduction decreased significantly compared with preoperative force
production. Copyright 2002 by the American Congress of Rehabilitation
Medicine and the American Academy of Physical Medicine and Rehabilitation
<10>
Unique Identifier
10976119
Medline Identifier
20433461
Authors
Wright RW. Heller MA. Quick DC. Buss DD.
Institution
Department of Orthopaedic Surgery, Washington University School of
Medicine at Barnes-Jewish Hospital, St. Louis, Missouri, USA.
wrightr@msnotes.wustl.edu
Title
Arthroscopic decompression for impingement syndrome secondary to an
unstable os acromiale.
Source
Arthroscopy. 16(6):595-9, 2000 Sep.
Abstract
PURPOSE: The purpose of this study was to examine cases of patients
with impingement syndrome secondary to an unfused, unstable, os
acromiale. TYPE OF STUDY: Retrospective case series. MATERIALS AND
METHODS: Twelve consecutive patients (13 shoulders) presented with
impingement symptoms in the presence of an os acromiale. The os
acromiale, at the meso-acromion level, was seen on standard radiographs.
The patients were all treated conservatively with rotator cuff
strengthening, stretching, anti-inflammatory medications, and steroid
injections. All patients underwent an impingement test with lidocaine,
resulting in complete relief of their pain. After failure of the
conservative management, the 12 patients (13 shoulders) underwent an
extended arthroscopic subacromial decompression. The goal of the modified
arthroscopic acromioplasty was resection of adequate bone to remove the
mobile anterior acromial tip. In general, this consisted of more bony
resection than the typical arthroscopic acromioplasty. Postoperatively,
the patients began a rehabilitation program emphasizing early range of
motion followed by isolated free-weight rotator cuff strengthening
exercises. Five shoulders had a partial-thickness tear of the rotator
cuff. Four involved less than 50% of the thickness of the rotator cuff.
These 4 partial-thickness tears underwent arthroscopic rotator cuff
debridement. One partial-thickness tear was greater than 50% and repair
was performed with a mini-open deltoid-splitting technique. RESULTS:
Results were evaluated using UCLA shoulder scoring. Preoperatively, the
score averaged 17. The 3-month postoperative score was 27, and at 6 and
12 months, averaged 28. The final follow-up score averaged 31. There were
11 satisfactory results with UCLA scores >/=28. Two unsatisfactory
results showed UCLA scores in the fair category. Full strength of the
anterior deltoid and rotator cuff muscles was achieved in all patients by
6 months postoperatively as evaluated by manual muscle testing. Twelve of
the 13 shoulders were rated by the patients as having a satisfactory
result. All of the patients rated their cosmetic results as acceptable.
There was no evidence of postoperative deltoid detachment. No patient
developed pain at the pseudarthrosis point. CONCLUSIONS: Given the
previously reported poor results with attempts at fusion of an unstable
os acromiale and open complete excision of meso-acromial fragments, the
authors conclude that an extended arthroscopic subacromial decompression
results in a reasonable outcome for patients with impingement syndromes
secondary to an unstable os acromiale.
<11>
Unique Identifier
9115554
Medline Identifier
97133493
Authors
McGuire DA. Barber FA. Hendricks SD.
Institution
Plano Orthopedic and Sports Medicine Center, Texas, USA.
Title
Meniscal impingement syndrome.
Source
Arthroscopy. 12(6):675-9, 1996 Dec.
Abstract
The meniscal impingement syndrome consists of three elements: impaction
on the anterior medial femoral condyle by the leading edge of the medial
meniscus, articular cartilage damage of at least Outerbridge grade 3, and
knee hyperextension of at least 5 degrees. This report reviews this
condition in a series of seven knees with an average follow-up of 39
months. The time from the onset of symptoms until surgery averaged 45
months. Treatment consisted of a thorough arthroscopic knee evaluation
and debridement of the articular cartilage fragmentation and any
impinging synovitis. Postoperative rehabilitation includes extension
block bracing, hamstring strengthening, and closed-chain exercise. With
this regimen, there was improvement in the Tegner scores and a reduction
in postoperative knee hyperextension. Identification of this uncommon
condition requires a complete evaluation of the medial femoral condyle in
patients with knee hyperextension.
<12>
Unique Identifier
9531129
Medline Identifier
98189614
Authors
Dalldorf PG. Alexander J. Lintner DM.
Institution
Department of Orthopaedic Surgery, Baylor College of Medicine, Houston,
Texas, USA.
Title
One- and two-incision anterior cruciate ligament reconstruction: a
biomechanical comparison including the effect of simulated closed-chain
exercise.
Source
Arthroscopy. 14(2):176-81, 1998 Mar.
Abstract
The purpose of this study was to evaluate the effect of simulated
closed-chain exercise on anterior translation in the anterior cruciate
ligament (ACL) reconstructed knee comparing patellar tendon grafts
secured with endoscopic and two-incision techniques. ACL reconstructions,
were performed on five matched pairs of fresh frozen cadaver lower
extremities. One of each pair had endoscopic (inside-out) placement of
the femoral interference screw and other had outside-in femoral screw
placement. A model for closed-chain exercise was developed to simulate
half squat exercises using a custom apparatus on the Material Testing
machine with a 356 N (80 lb) axial load and 40 N (9 lb) static hamstring
force. Knee motion from near full extension to 60 degrees flexion was
achieved by varying the quadricep force. One thousand squats were
performed, and KT-1000 arthometry was done before and after cycling each
specimen. The femur-graft-tibia constructs were then stressed to failure.
Closed-chain cycling resulted in no significant change in anterior
translation in either group. The mean maximum load to failure of the
femur-graft-tibia construct was 340.4N in the one-incision group and
434.2 N in the two-incision group. P=.048 was considered statistically
significant. Anterior translation did not increase after 1,000 simulated
half knee bends in either the one- or two-incision groups. Shallow knee
bends are an important part of aggressive rehabilitation programs, and
our data support the position that these closed-chain exercises do not
deleteriously affect the graft. Though the maximum strength to failure
differed significantly between the one- and two-incision groups, both
techniques offered sufficient strength to withstand an aggressive
simulated rehabilitation protocol.
<13>
Unique Identifier
9731386
Medline Identifier
98401573
Authors
Hefzy MS. al Khazim M. Harrison L.
Institution
Department of Biological & Medical Research, King Faisal Specialist
Hospital and Research Center, Riyadh, Kingdom of Saudi Arabia.
Title
Co-activation of the hamstrings and quadriceps during the lunge
exercise.
Source
Biomedical Sciences Instrumentation. 33:360-5, 1997.
Abstract
The anterior lunge exercise is a closed chain kinetic exercise that has
been developed to improve the function of the lower limb and to
strengthen the hamstrings and quadriceps, simultaneously. In this study,
a three-dimensional biomechanical analysis of this exercise was conducted
in order to understand the mechanics of this rehabilitation activity.
Experimental conditions were recorded using an active optoelectronic
kinematic data capture system (OPTOTRAK), two force plates (AMTI) and
electromyography (EMG). Data were collected from healthy male subjects
while performing several lunges. When the distance between the toe of the
rear leg and the heel of the front leg (lunging distance) was maximum, a
large net flexion moment was predicted in the front leg in the extented
position. This moment was reversed to a large net extension moment in the
flexed position. A large increase in the net extension moment in the rear
leg was also predicted as the front knee was bent from 5 degrees to 90
degrees of flexion. These data suggest that quadriceps and hamstring
muscles co-contraction occur during a maximum lunge in the front leg when
it is in the flexed position.
<14>
Unique Identifier
11347451
Medline Identifier
21245949
Authors
Ruttley TM. Colosky PE Jr. James SP.
Institution
Department of Mechanical Engineering and Biomedical Engineering
Program, Colorado State University, Fort Collins, CO 80523, USA.
Title
A gravity-independent constant force resistive exercise unit.
Source
Biomedical Sciences Instrumentation. 37:87-93, 2001.
Abstract
This study designed, developed and tested a novel, practical, gravityindependent exercise machine, the Constant Force Resistance Exercise Unit
(CFREU). A CFREU prototype was designed and built according to National
Aeronautic and Space Administration (NASA) hardware and physiological
requirements, and was evaluated for potential exercise countermeasure
viability. Life cycle data exhibit lower life than required by NASA
guidelines; however, current CFREU re-designs are addressing this issue.
Electromyography (EMG) data indicate that the CFREU used on the ground
and in microgravity during exercise is capable of providing forces on the
muscles that are similar to a standard free-weight machine used in
gravity. Given the results of this study, the CFREU has proven to be a
viable potential resistive exercise countermeasure to the deconditioning
of the musculoskeletal system in microgravity.
<15>
Unique Identifier
10821873
Medline Identifier
20283435
Authors
Maddalozzo GF. Snow CM.
Institution
Bone Research Laboratory, Department of Exercise and Sport Science, 20
Women's Building, 230 Langton Hall, Oregon State University, Corvallis,
Oregon 97331-6802, USA.
Title
High intensity resistance training: effects on bone in older men and
women.
Source
Calcified Tissue International. 66(6):399-404, 2000 Jun.
Abstract
There is evidence that high intensity resistance training promotes bone
maintenance in older women, however, the effect of high intensity free
weight training has not been investigated in older men or women.
Furthermore, little is known about the chronic effect of weight training
on serum insulin growth factor-I (IGF-I) in this population. We compared
the effects of a moderate intensity seated resistance-training program
with a high intensity standing free weight exercise program on bone mass
and serum levels of IGF-I and IGFBP3 in healthy older men and women.
Twenty-eight men (54.6 +/- 3. 2 years) and 26 nonestrogen-replaced women
(52.8 +/- 3.3 years) served as their own controls for 12 weeks, then were
randomly assigned to a moderate or high intensity training group and
trained three times/week for 24 weeks. Prior to and after the control
period and at the end of training, bone mass and body composition were
assessed by dual energy X-ray absorptiometry (DXA), muscle strength by
isokinetic dynamometry, muscular power by Wingate Anaerobic Power Test,
and IGF-I by radioimmunoassay (RIA). A repeated measures analysis of
covariance (ANCOVA) revealed that high intensity training resulted in a
gain in spine BMD in men (1.9%), P < 0.05, but not in women, whereas
moderate intensity training produced no changes in either gender at this
site. Increases were observed at the greater trochanter, P < 0.03, in men
regardless of training intensity, but not in women at any hip site.
However, when compared with zero, both men and women in the high
intensity group demonstrated significant increases in trochanteric BMD
(1.3% and 2. 0%, respectively) and a decrease in femoral BMD (-1.8%).
Neither circulating serum IGF-I nor IGFBP3 were altered by either
training regimen, but both training programs resulted in improvements in
total body strength (37.62%) and lean mass (males 4.1%, females 3. 1%).
We conclude that although resistance training of moderate to high
intensity produced similar muscle changes in older adults, a higher
magnitude is necessary to stimulate osteogenesis at the spine. However,
at the spine, intensity was not sufficient to offset low levels of
estrogen in early postmenopausal women. Furthermore, bone changes were
not accompanied by changes in circulating serum levels of IGF-I or
IGFBP3.
<16>
Unique Identifier
10656977
Medline Identifier
20124275
Authors
McGinty G. Irrgang JJ. Pezzullo D.
Institution
Department of Physicial Therapy, University of Pittsburgh School of
Health and Rehabilitation Sciences, Room 6010-A, Forbes Tower, Meyran
Avenue, Pittsburgh, PA 15260, USA.
Title
Biomechanical considerations for rehabilitation of the knee. [Review]
[39 refs]
Source
Clinical Biomechanics. 15(3):160-6, 2000 Mar.
Abstract
Knowledge of the anatomy and biomechanics of the knee is critical for
successful rehabilitation following knee injury and/or surgery.
Biomechanics of both the tibiofemoral and patellofemoral joints must be
considered. The purpose of this paper is to provide a framework for
rehabilitation of the knee by reviewing the biomechanics of the
tibiofemoral and patellofemoral joints. This will include discussion of
the relevant arthrokinematics as well as the effects of open and closed
chain exercises. The implications for rehabilitation of the knee will be
highlighted. [References: 39]
<17>
Unique Identifier
7954889
Medline Identifier
95042829
Authors
Wilk KE.
Institution
American Sports Medicine Institute, Birmingham, Alabama.
Title
Rehabilitation of isolated and combined posterior cruciate ligament
injuries. [Review] [70 refs]
Source
Clinics in Sports Medicine. 13(3):649-77, 1994 Jul.
Abstract
In conclusion, PCL injuries occur more commonly than previously noted.
The PCL-deficient knee is a serious pathology; it is one of functional
disability, not functional instability as seen with an ACL disruption.
This functional disability is secondary to pain and inflammation from
articular cartilage degeneration. The degeneration process occurs over a
period of time normally greater than 5 years; eventually knee function is
seriously limited. The rehabilitation of the PCL reconstructive or
nonoperative patient is greatly dependent on dynamic quadriceps
stability. The biomechanics of the PCL and PLC during various exercises
are not well understood; however, research is being performed to advance
the clinical management following these injuries. The clinician must
realize that tremendous tibiofemoral shear forces are created during
various knee exercises, in both the closed and open chain. In particular,
various knee exercises, in both the closed and open chain. In particular,
there are tremendous stresses applied to the PCL during OKC-resisted knee
flexion. The clinician must also realize the role of the hamstrings
during most closed chain exercises; therefore the author recommends an
early program emphasizing isolated open chain quadriceps strengthening
progressing to closed chain drills once adequate quadriceps strength has
been established. The numerous clinical challenges for the rehabilitation
team to hurdle when treating a PCL-injured knee patient have been
discussed in this article. The PCL rehabilitation program can no longer
be thought of an an ACL rehabilitation program "turned around." The
anatomy, biomechanics, and natural history of the PCL-deficient knee
differs dramatically from the ACL-deficient knee, and the treatment
approach should reflect these considerations. [References: 70]
<18>
Unique Identifier
7712559
Medline Identifier
95228140
Authors
Kibler WB.
Institution
Lexington Clinic, Sports Medicine Center, Kentucky, USA.
Title
Biomechanical analysis of the shoulder during tennis activities.
Source
Clinics in Sports Medicine. 14(1):79-85, 1995 Jan.
Abstract
Biomechanical analysis of the shoulder in tennis is still in early
stages; however, the available data do allow some conclusions and some
recommendations for conditioning, evaluation, and rehabilitation. Normal
shoulder biomechanical function requires an intact kinetic chain to
create the energy, produce the forces and stabilize the joint in tennis
activities. Only through this mechanism can optimum performance with
minimal injury risk be maintained. Conditioning of the shoulder for
tennis should take this into account. Exercises should involve force
generation by the large leg and trunk muscles, scapular stabilization,
and closed chain co-contraction activity for the shoulder stabilizers.
Similarly, clinical evaluation for shoulder problems must include
assessment of areas distant to the shoulder. Kinetic chain failure can
cause extra stress on the shoulder, causing or exacerbating clinical
symptoms at the shoulder. Clinical evaluation of shoulder joint
structures also is enhanced by knowledge of the integration of the
constraint systems, and the fact that more than one system may be
involved in shoulder pathology. Finally, rehabilitation efforts for
shoulder problems need to focus on allowing functional return of the
shoulder joint in the context of the entire kinetic chain of tennis
specific activity. Rehabilitation of all areas of kinetic chain failure,
such as trunk inflexibility or scapulothoracic dyskinesis, should be
undertaken in conjunction with rehabilitation techniques for the
shoulder. The sports medicine clinician will have a more functional
framework for assessing shoulder activity and injury in tennis through
the understanding of these biomechanical principles.
<19>
Unique Identifier
11138574
Medline Identifier
21019511
Authors
Walker M. Klentrou P. Chow R. Plyley M.
Institution
Faculty of Applied Health Sciences, Brock University, St Catharines,
Ontario, Canada. nota@arnie.pec.brocku.ca
Title
Longitudinal evaluation of supervised versus unsupervised exercise
programs for the treatment of osteoporosis.
Source
European Journal of Applied Physiology. 83(4 -5):349-55, 2000 Nov.
Abstract
The efficacy of an exercise program was investigated in a study of 89
post-menopausal women with osteoporosis over a 5-year follow-up period.
The study attempted to examine and compare potential differences in bone
mineral density (BMD), incidence of fracture, and loss of height, between
a group of patients (n = 42) who attended the supervised exercise program
in the hospital, and a group (n = 47) who exercised at home. Habitual
physical activity, as estimated using the Harvard Alumni Questionnaire,
and a Physical Activity Index were combined to obtain an estimate of
overall weekly caloric expenditure over the 5-year period. The exercise
program involved weight-bearing aerobic activities of moderate intensity,
and muscle strengthening exercise using free weights. The mean percentage
change for the lumbar BMD was + 4.4% in the hospital group and +3.4% in
the home group while for the femoral neck BMD was + 1.1% in the hospital
group and -0.9% in the home group. There was a significant reduction in
the number of fractures and no significant loss of height over the 5-year
follow-up period for both groups. As the correlation between BMD and
weekly caloric expenditure of the subjects was not significant, no
conclusion can be drawn as to the minimum level of caloric expenditure
necessary in order to retard bone loss. It was concluded that for the
post-menopausal women with osteoporosis who participated in the program
it was possible to stabilize their height and the BMD of the lumbar site,
and to reduce fractures over the 5-year study period regardless if they
exercised in a supervised or in an unsupervised setting.
<20>
Unique Identifier
11072776
Medline Identifier
20522928
Authors
Osternig LR. Ferber R. Mercer J. Davis H.
Institution
Department of Exercise and Movement Science, University of Oregon,
Eugene 97403, USA. louiso@oregon.uoregon.edu
Title
Human hip and knee torque accommodations to anterior cruciate ligament
dysfunction.
Source
European Journal of Applied Physiology. 83(1):71-6, 2000 Sep.
Abstract
It has been postulated that the adaptations of lower extremity function
exhibited by anterior cruciate ligament (ACL) deficient and post-ACL
surgical patients represent early accommodations to the loss of ACL
function after injury so that excessive anterior displacement of the
tibia is prevented. Prior studies have suggested that compensation
patterns in ACL deficient and post-ACL surgical subjects may affect joint
moments of the knee as well as the hip. However, the variance in knee and
hip forces between ACL deficient, post-surgical ACL and uninjured groups
has not been clearly elucidated. The purpose of this study was to assess
hip:knee extensor torque ratios relative to anterior tibia shear in presurgical-ACL deficient, post-surgical and uninjured subjects.
Measurements of hip and knee joint moments and anterior tibia shear were
recorded from 45 injured and uninjured subjects (21 men, 24 women) during
lower extremity, variable resistance exercise. Anterior tibia shear was
computed by decomposing joint moments and reaction forces according to a
model derived from cadaver knee dissections and radiography, in
combination, to estimate the tibio-femoral compressive and shear forces
generated by the patellar tendon at various angles throughout the knee
joint range. Three groups of subjects were studied: recently injured ACL
deficient pre-surgical subjects who were scheduled for immediate surgery
(PRE; n = 15); postsurgical subjects who had undergone ACL reconstructive
surgery at least 1 year prior to testing (POST; n = 15); and uninjured
controls (CON; n = 15). All PRE and POST subjects had a normal
contralateral limb. Tests were conducted under six conditions: 1 and 1.5
Hz cadence and maximal speed at 33% and 50% one repetition maximum
resistance. The results revealed that the hip:knee ratios were
significantly greater for the post-ACL surgical group than the PRE and
CON groups (P<0.01; P<0.03). There were significant negative correlations
between the hip extensor:knee extensor torque ratios and maximal anterior
tibia shear across all groups. The hip:knee extensor torque ratio
increased with decreased anterior tibia shear in all groups with
significant correlations ranging from -0.55 to -0.88 (P<0.01) for the
injured limbs of PRE and POST groups, and -0.64 to -0.78; (P<0.01) for
the CON group. The highest overall correlations were found for the postsurgical subjects. The results revealed that anterior tibia shear
declined significantly with speed (P<0.01) in all groups. However, the
converse was true for the hip:knee extensor torque ratio across speeds.
The ratio increased significantly with speed (P<0.001) for all groups at
the 33% and 50% resistances. The results suggest (1) that post-ACL
surgical subjects appear to accommodate to ACL substitution by using hip
extensors to a significantly greater extent than the uninjured controls
in closed-chain lower extremity exercise; (2) that the hip:knee extensor
torque ratio is significantly related to the magnitude of anterior tibia
shear; and (3) that the anterior tibia shear is significantly reduced as
speed increases in closed-chain lower extremity exercise.
<21>
Unique Identifier
8727745
Medline Identifier
96284375
Authors
Shelbourne KD. Patel DV.
Institution
Methodist Sports Medicine Center, Indianapolis, Indiana, USA.
Title
Rehabilitation after autogenous bone-patellar tendon-bone ACL
reconstruction.
Source
Instructional Course Lectures. 45:263-73, 1996.
Abstract
In the past decade, changes in the rehabilitation of patients with ACL
injuries have made a dramatic impact on the management of the surgically
treated ACL-deficient knee. Our rehabilitation program following the ACL
reconstruction has been developed over the past 12 years. With close
follow-up of our patients, we have modified the rehabilitation program in
an attempt to eliminate postoperative complications, ensure long-term
knee stability, and allow a safe and rapid return to athletic activities.
Our present rehabilitation protocol is divided into four phases. The
initial phase encompasses the preoperative period. The second phase
involves the first 2 weeks after ACL reconstruction. The third phase
extends from 2 to 5 weeks postoperation, and the final phase (> than 5
weeks postoperation) involves a safe return to athletic activities. An
aggressive preoperative phase and close attention to full hyperextension,
control of swelling, and good leg control during the first postoperative
phase are the cornerstones of the rehabilitation program. We continue to
evaluate our results closely and to advance our rehabilitation program
guided by our patients and continuous follow-up evaluations. We propose
that the avoidance of immediate surgery and appropriate preoperative
patient preparation, along with postoperative rehabilitation program that
emphasizes extension and closed chain function exercises, will optimize
the final result.
<22>
Unique Identifier
9130147
Medline Identifier
97276394
Authors
Ninos JC. Irrgang JJ. Burdett R. Weiss JR.
Institution
Physical Therapy Services, Allentown Sports Medicine and Human
Performance Center, PA 18103, USA.
Title
Electromyographic analysis of the squat performed in self-selected
lower extremity neutral rotation and 30 degrees of lower extremity turnout from the self-selected neutral position.
Source
Journal of Orthopaedic & Sports Physical Therapy. 25(5):307-15, 1997
May.
Abstract
Little research is available on the muscle activity patterns of the
lower extremity muscles during dynamic closed chain squatting activities.
The purpose of this study was to examine the effect of lower extremity
position during an Olympic squat on the muscle activity patterns of the
vastus medialis, vastus lateralis, semimembranosus/semitendinosus, and
biceps femoris. Twenty-five healthy, untrained subjects, 18-35 years old,
were randomly assigned initial squatting positions of either selfselected neutral or 30 degrees of lower extremity turn-out from the selfselected neutral position. Surface electromyography and motion analysis
data were collected simultaneously in 10 degrees intervals and analyzed
from 10-60 degrees of knee flexion in both the ascending and descending
phases of the squat. A four-way analysis of variance indicated that the
main effect of lower extremity position and the interaction of extremity
position and knee joint angles were not found to cause significant
changes in muscle activity patterns. Significant changes in muscle
activity did occur with changes in knee flexion angles in the vastus
medialis and vastus lateralis but not in the
semimembranosus/semitendinosus or biceps femoris.
<23>
Unique Identifier
8808512
Medline Identifier
96404234
Authors
Doucette SA. Child DD.
Institution
Mountain West Physical Therapy, Logan, UT 84341, USA.
Title
The effect of open and closed chain exercise and knee joint position on
patellar tracking in lateral patellar compression syndrome.
Source
Journal of Orthopaedic & Sports Physical Therapy. 23(2):104-10, 1996
Feb.
Abstract
There are numerous rehabilitation protocols for patellofemoral
problems, but there is little objective data to determine the most
effective exercise program to conservatively treat this disorder. The
purpose of this study was to determine the effect of open and closed
chain exercise and knee joint position on patellar tracking in lateral
patellar compression syndrome. Computed tomography scans of the
patellofemoral joint were performed with the leg in three muscle
conditions and at five knee angles in 16 subjects with lateral patellar
compression syndrome. Patellar tracking was evaluated by measuring
congruence angle. Relaxed and closed chain conditions demonstrated
improved congruence as compared with the open chain condition at 0, 10,
and 20 degrees of knee flexion (p < .0001). Open chain strengthening
techniques appear to be most appropriate after 30 degrees of knee
flexion. The three muscle conditions demonstrated progressively improved
patellar congruence from 0 to 40 degrees of knee flexion.
<24>
Unique Identifier
8467333
Medline Identifier
93222879
Authors
Wilk KE. Andrews JR.
Institution
HEALTHSOUTH Rehabilitation Corporation, Birmingham, AL.
Title
The effects of pad placement and angular velocity on tibial
displacement during isokinetic exercise.
Source
Journal of Orthopaedic & Sports Physical Therapy. 17(1):24-30, 1993
Jan.
Abstract
The purpose of this study was to compare the effects of proximal single
resistance pad placement (PSPP) and distal single pad placement (DSPP) on
tibial displacement during isokinetic exercise on anterior cruciate
ligament (ACL)-deficient knees. This study is important to the clinician
because it documents tibial displacement during open chain isokinetic
knee extension exercise at various isokinetic speeds. In addition, this
study documents the range of motion where the greatest amount of anterior
tibial displacement occurs. The anterior displacement of the tibia was
recorded by a computerized knee laxity testing device during isokinetic
exercise. Data were collected from 12 ACL-deficient knees. Each subject
was tested on an OSI Knee Signature System for quantifiable tibial
displacement during a Lachman's test, anterior drawer test, and active
vs. passive knee extension. Following this, each subject was tested on a
Biodex isokinetic dynamometer at isokinetic velocities of 60, 180, and
300 degrees/sec with the computerized knee laxity testing device in
place. Pad placement consisted of distal single pad placement, which is 1
inch proximal to the medial malleolus, and proximal single pad placement,
which is 3 inches proximal to the DSPP location. The testing procedure
was standardized, and peak torque was monitored to ensure consistent
maximal effort throughout the study. The results indicated that PSPP
resulted in less anterior tibial displacement at all three test speeds.
The peak anterior tibial displacement occurred in a range from 30 to 15
degrees of knee flexion at both pad placements and all three test
speeds.(ABSTRACT TRUNCATED AT 250 WORDS)
<25>
Unique Identifier
11034431
Medline Identifier
20487244
Authors
Beckham SG. Earnest CP.
Institution
Department of Exercise Sport and Health Studies, University of Texas at
Arlington, 76019, USA.
Title
Metabolic cost of free weight circuit weight training.
Source
Journal of Sports Medicine & Physical Fitness. 40(2):118-25, 2000 Jun.
Abstract
BACKGROUND: Free weight circuit weight training (CWT) classes are
popular group exercise classes designed to improve aerobic capacity, body
composition, and muscular strength and endurance. The purpose of this
investigation was to determine the training intensity and caloric
expenditure associated with free weight CWT. METHODS: Twelve males and
eighteen females (age 25.1+/-6.6 years) participated in a Bruce treadmill
test to measure VO2max (47.9+/-10.6 ml/kg min). Subjects subsequently
performed a learning trial, exercising to a 14 minute video-taped free
weight CWT sequence which included squats and upper body exercises
performed consecutively. All subjects then completed two randomly
assigned video exercise bouts with light resistance (LR = 1.4 kg for
males and females) and moderate resistance (MR = 5.9 kg for females and
10.5 kg for males), loads recommended by instructors for sedentary and
fit individuals, respectively. RESULTS: Statistical analysis by RM ANOVA
(p<0.0036) revealed significant increases in absolute and relative VO2,
HR, and energy expenditure at MR as compared to LR for males and females.
Mean VO2 and caloric expenditure values at MR were 15.7+/-2.3 ml/kg min
and 6.21+/-1.01 kcal/min for males and 13.5+/-1.4 ml/kg min and 4.04+/1.45 kcal/min for females. Associated HR responses were 129.5+/-18.4 and
119.2+/-19.4 bpm for males and females, respectively. The training
stimulus was <32% VO2max, significantly below ACSM recommendations (50%
VO2max) for improving cardiovascular fitness; HR criteria (60% HRmax),
however were met. Free weight CWT performed with loads < or =10.5 kg may
not provide a sufficient cardiovascular training stimulus. CONCLUSIONS:
HR should not be used to assess exercise intensity in these classes.
<26>
Unique Identifier
11034431
Medline Identifier
20487244
Authors
Beckham SG. Earnest CP.
Institution
Department of Exercise Sport and Health Studies, University of Texas at
Arlington, 76019, USA.
Title
Metabolic cost of free weight circuit weight training.
Source
Journal of Sports Medicine & Physical Fitness. 40(2):118-25, 2000 Jun.
Abstract
BACKGROUND: Free weight circuit weight training (CWT) classes are
popular group exercise classes designed to improve aerobic capacity, body
composition, and muscular strength and endurance. The purpose of this
investigation was to determine the training intensity and caloric
expenditure associated with free weight CWT. METHODS: Twelve males and
eighteen females (age 25.1+/-6.6 years) participated in a Bruce treadmill
test to measure VO2max (47.9+/-10.6 ml/kg min). Subjects subsequently
performed a learning trial, exercising to a 14 minute video-taped free
weight CWT sequence which included squats and upper body exercises
performed consecutively. All subjects then completed two randomly
assigned video exercise bouts with light resistance (LR = 1.4 kg for
males and females) and moderate resistance (MR = 5.9 kg for females and
10.5 kg for males), loads recommended by instructors for sedentary and
fit individuals, respectively. RESULTS: Statistical analysis by RM ANOVA
(p<0.0036) revealed significant increases in absolute and relative VO2,
HR, and energy expenditure at MR as compared to LR for males and females.
Mean VO2 and caloric expenditure values at MR were 15.7+/-2.3 ml/kg min
and 6.21+/-1.01 kcal/min for males and 13.5+/-1.4 ml/kg min and 4.04+/1.45 kcal/min for females. Associated HR responses were 129.5+/-18.4 and
119.2+/-19.4 bpm for males and females, respectively. The training
stimulus was <32% VO2max, significantly below ACSM recommendations (50%
VO2max) for improving cardiovascular fitness; HR criteria (60% HRmax),
however were met. Free weight CWT performed with loads < or =10.5 kg may
not provide a sufficient cardiovascular training stimulus. CONCLUSIONS:
HR should not be used to assess exercise intensity in these classes.
<27>
Unique Identifier
11832872
Medline Identifier
21822366
Authors
Van Zant RS. Conway JM. Seale JL.
Institution
Department of Physical Therapy, University of Findlay, Findlay, Ohio
45840, USA.
Title
A moderate carbohydrate and fat diet does not impair strength
performance in moderately trained males.
Source
Journal of Sports Medicine & Physical Fitness. 42(1):31-7, 2002 Mar.
Abstract
BACKGROUND: The purpose of this investigation was to study the effects
of varied levels of dietary carbohydrate and fat intake on exercise
training and high intensity exercise performance in moderately strength
trained, aerobic trained and untrained males. METHODS: Subjects (6
strength trained, 6 aerobically trained serving as an active control
group, 6 sedentary) consumed isoenergetic diets considered either high
CHO/low fat (HC/LF: total energy 62% CHO, 20% fat, 18% protein) or
moderate CHO and fat (MC/MF: total energy 42% CHO, 40% fat, 18% protein)
in a randomly assigned crossover design. Each dietary treatment was three
weeks in length. Prior to the study and following each dietary treatment,
muscular strength and endurance was determined (isokinetic knee extension
and flexion, standard concentric free weight bench press). RESULTS: No
differences as a result of the dietary treatment were seen in isokinetic
peak torque, total work production, single repetition maximum (1 RM)
bench press, or number of bench press repetitions at 80% 1 RM. Selfreported exercise log data showed no dietary effect on the subject's
ability to maintain training level. CONCLUSIONS: These findings indicate
that varying dietary macronutrient content (HC/LF or MC/MF) had no effect
on exercise training or strength exercise performance in moderately
trained (aerobic and strength) or sedentary males.
<28>
Unique Identifier
11832877
Medline Identifier
21822371
Authors
Engels HJ. Currie JS. Lueck CC. Wirth JC.
Institution
Division of HPR--Exercise Science, Wayne State University, Detroit,
Michigan 48202, USA. Engels@wayne.edu
Title
Bench/step training with and without extremity loading. Effects on
muscular fitness, body composition profile, and psychological affect.
Source
Journal of Sports Medicine & Physical Fitness. 42(1):71-8, 2002 Mar.
Abstract
BACKGROUND: To study the effect of bench/step group exercise with and
without extremity loading on muscular fitness, body composition, and
psychological affect. METHODS: Experimental design: a prospective
training study. SETTING: general community fitness center. PARTICIPANTS:
44 healthy adult females (age: 21-51 yrs). Interventions: 12 weeks of
bench/ step exercise (3 sessions/week, 50 min/session, 60-90% HRmax).
Subjects were randomly assigned to groups that trained with (WT, n=16)
and without (NWT, n=16) 0.68 kg/ankle and 1.36 kg/hand weights while 12
subjects served as non-training controls (NTC). MEASURES: Pre- and
postintervention muscular strength and endurance for knee and elbow
flexion and extension, and for shoulder abduction and adduction were
examined by isokinetic dynamometry. Body composition was assessed with
hydrostatic weighing and psychological affect by questionnaire. RESULTS:
Thirty-two subjects completed the study. ANOVA revealed that pre- to
postintervention changes for body fat (2.6%), fat-free weight (+0.7 kg),
fat weight (-1.9 kg), and knee flexion peak torque were significantly
different in the bench/step exercise trained (WT+NWT) compared to the NTC
study group. Specific comparisons of muscle strength and endurance change
scores of WT+NWT relative to NTC, and of WT relative to NWT revealed no
other significant differences between groups. Positive and negative
affective states were similar among study groups before and after the
intervention. CONCLUSIONS: Participation in bench/step group exercise
improved body composition but was of limited or no value as a modality to
change muscular fitness and psychological affect in healthy adult
females. The use of ankle and hand weights failed to enhance training
adaptations.
<29>
Unique Identifier
10737266
Medline Identifier
20199527
Authors
Too D. Landwer GE.
Institution
Department of Physical Education and Sport, State University of New
York at Brockport, 14420-2989, USA. dtoo@po.brockport.edu
Title
The effect of pedal crank arm length on joint angle and power
production in upright cycle ergometry.
Source
Journal of Sports Sciences. 18(3):153-61, 2000 Mar.
Abstract
The aim of this study was to determine the effect of five pedal crank
arm lengths (110, 145, 180, 230 and 265 mm) on hip, knee and ankle angles
and on the peak, mean and minimum power production of 11 males (26.6+/3.8 years, 179+/-8 cm, 79.6+/-9.5 kg) during upright cycle ergometry.
Computerized 30 s Wingate power tests were performed on a free weight
Monark cycle ergometer against a resistance of 8.5% body weight. Joint
angles were determined, with an Ariel Performance Analysis System, from
videotape recorded at 100 Hz. Repeated-measures analysis of variance and
contrast comparisons revealed that, with increasing crank arm lengths,
there was a significant decrement in the minimum hip and knee angles, a
significant increment in the ranges of motion of the joints, and a
parabolic curve to describe power production. The largest peak and mean
powers occurred with a crank arm length of 180 mm. We conclude that 35 mm
changes in pedal crank arm length significantly alter both hip and knee
joint angles and thus affect cycling performance.
<30>
Unique Identifier
11543414
Medline Identifier
20604482
Authors
Bamman MM. Caruso JF.
Institution
Division of Exercise Physiology, Department of Human Studies, The
University of Alabama at Birmingham, USA.
Title
Resistance exercise countermeasures for space flight: implications of
training specificity.
Source
Journal of Strength & Conditioning Research. 14(1):45-9, 2000 Feb.
Abstract
While resistance exercise should be a logical choice for prevention of
strength loss during unloading, the principle of training specificity
cannot be overlooked. Our purpose was to explore training specificity in
describing the effect of our constant load exercise countermeasure on
isokinetic strength performance. Twelve healthy men (mean +/- SD: 28.0
+/- 5.2 years, 179.4 +/- 3.9 cm, 77.5 +/- 13.6 kg) were randomly assigned
to no exercise or resistance exercise (REX) during 14 days of bed rest.
REX performed five sets of leg press exercise to volitional fatigue (6-10
repetitions) every other day. Unilateral isokinetic concentric-eccentric
knee extension testing performed before and on day 15 prior to
reambulation included torque-velocity and power-velocity relationships at
four velocities (0.52, 1.75, 2.97, and 4.19 rad s-1), torque-position
relationship, and contractile work capacity (10 repetitions at 1.05 rad
s-1). Two (group) x 2 (time) ANOVA revealed no group x time interactions;
thus, groups were combined. Across velocities, angle-specific torque fell
18% and average power fell 20% (p < 0.05). No velocity x time or mode
(concentric/eccentric) x time interactions were noted. Torque x position
decreased on average 24% (p < 0.05). Total contractile work dropped 27%
(p < 0.05). Results indicate bed rest induces rapid and marked reductions
in strength and our constant load resistance training protocol did not
prevent isokinetic strength losses. Differences between closed-chain
training and open-chain testing may explain the lack of protection.
<31>
Unique Identifier
11834118
Medline Identifier
21824090
Authors
Brindle TJ. Nyland J. Ford K. Coppola A. Shapiro R.
Institution
Biodynamics Laboratory, University of Kentucky, Lexington, Kentucky
40506, USA.
Title
Electromyographic comparison of standard and modified closed-chain
isometric knee extension exercises.
Source
Journal of Strength & Conditioning Research. 16(1):129-34, 2002 Feb.
Abstract
The purpose of this study was to compare electromyographic (EMG)
activity during open kinetic chain (OKC) and a modified closed kinetic
chain (MCKC) knee extension exercises. Both OKC and closed kinetic chain
(CKC) exercises provide benefits when devising conditioning programs;
however, there are no exercises that combine the benefits of both
exercises. Subjects performed maximum isometric knee extensions for both
traditional OKC and MCKC knee extension exercises. Surface electrodes
were placed on 8 lower-extremity muscles. One second of integrated EMG
activity followed 95% maximal knee extension force. The following muscles
demonstrated greater EMG activity during the MCKC vs. the OKC knee
extension exercises: vastus medialis, medial hamstring, lateral
hamstrings, and gluteus maximus. There was no difference between force
output between the 2 conditions. This study demonstrates that
modifications to traditional OKC exercises demonstrate some
characteristics of CKC exercises, and therefore provide another avenue of
rehabilitation or strengthening.
<32>
Unique Identifier
11726263
Medline Identifier
21583685
Authors
Morriss CJ. Tolfrey K. Coppack RJ.
Institution
Department of Exercise and Sport Science, Manchester Metropolitan
University, Crewe + Alsager Faculty, Alsager, Stoke-on-Trent, ST7 2HL,
UK.
Title
Effects of short-term isokinetic training on standing long-jump
performance in untrained men.
Source
Journal of Strength & Conditioning Research. 15(4):498-502, 2001 Nov.
Abstract
The purpose of this study was to examine the effects of a 6-week
isokinetic training program on quadriceps and hamstrings peak torque (PT)
and standing long-jump (SLJ) performance. Twelve untrained men (age 31.4
+/- 4.2 years, mean +/- SD) were tested at a velocity of 1.75 rad.s(-1)
(100 degrees.s(-1)), before and after a 6-week control period and on
completion of a 6-week training program. Training consisted of 3 sets of
10 repetitions, 3 days per week, for 6 weeks. Repeated-measures analysisof-variance analyses revealed that quadriceps PT increased, on average,
by 10.5% as a result of training (p < 0.01). No significant changes in
hamstrings PT (p = 0.062) and SLJ performance occurred as a result of
training (p > 0.05). The major finding of this study was that PT gains
subsequent to isokinetic resistance training did not influence functional
performance. That open-chain training did not affect the performance of a
closed-chain activity is unsurprising, but on these grounds of
nonfunctionality, the use of moderate velocity isokinetic dynamometry in
rehabilitation and performance assessment for closed-chain sports needs
addressing in future research.
<33>
Unique Identifier
11708701
Medline Identifier
21565015
Authors
Baker D. Nance S. Moore M.
Institution
Department of Sport and Exercise Science, Sunshine Coast University,
QLD, Australia.
Title
The load that maximizes the average mechanical power output during
explosive bench press throws in highly trained athletes.
Source
Journal of Strength & Conditioning Research. 15(1):20-4, 2001 Feb.
Abstract
The power output generated with different barbell loads and which
resistance generated the maximum mechanical power output (Pmax) during
explosive bench press-type throws (BT) in a smith machine device were
investigated in power-trained athletes. Thirty-one rugby league players
were tested for 1 repetition maximum (1RM) free-weight bench press
strength (1RM BP). Maximal power output was assessed by the Plyometric
Power System during BT using resistances of 40, 50, 60, 70, and 80 kg (BT
P40, BT P50, BT P60, BT P70, and BT P80). It was found that BT Pmax
occurred with resistance of 70.1 +/- 7.9 kg, representing 55 +/- 5.3% of
1RM BP of 129.7 +/- 14.3 kg. The power output with all loads except the
BT P70 were different from the BT Pmax. The BT P70 and BT P80 were not
different from each other. Furthermore, the BT P60 and BT P80 were not
different from each other. This suggests that although resistances of 55%
1RM BP may maximize power output during explosive BT, loads in the range
of 46-62% also allow for high power outputs. Resistances of 31-45% of 1RM
BP resulted in significantly lower power outputs. Compared with previous
research of BT in strength-trained athletes, the results of this
investigation suggest that power-trained athletes may generate their Pmax
at higher percentages of 1RM.
<34>
Unique Identifier
11710399
Medline Identifier
21566627
Authors
Livolsi JM. Adams GM. Laguna PL.
Institution
Division of Kinesiology and Health Promotion, California State
University-Fullerton, 92634-9480, USA.
Title
The effect of chromium picolinate on muscular strength and body
composition in women athletes.
Source
Journal of Strength & Conditioning Research. 15(2):161-6, 2001 May.
Abstract
Fifteen women softball athletes were randomly divided into 2 groups,
the chromium treatment group (n = 8) and the placebo control group (n =
7) to examine the effect of chromium, in the form of chromium picolinate
(CrPic) supplementation, on muscular strength, body composition (body
weight, percent body fat, and lean body mass), and urinary excretion. The
CrPic supplementation consisted of a 500 ug dosage taken once per day.
All participants trained 3 times per week with 2-3 sets of 8-12
repetitions at 80% of 1 repetition maximum (1RM) using variable
resistance machines and free weights. No significant (p < 0.05)
differences in muscular strength or body composition were found after 6
weeks of resistance training. In addition, chromium excretion (microg per
24 every hours) was examined and increased significantly with the
treatment group after the 6-week period.
<35>
Unique Identifier
11730332
Medline Identifier
21588126
Authors
Kibler WB. Livingston B.
Institution
Lexington Sports Medicine Center, 1221 South Broadway, Lexington, KY
40504, USA.
Title
Closed-chain rehabilitation for upper and lower extremities. [Review]
[26 refs]
Source
Journal of the American Academy of Orthopaedic Surgeons. 9(6):412-21,
2001 Nov-Dec.
Abstract
Closed-chain exercise protocols are used extensively in rehabilitation
of knee injuries and are increasingly used in rehabilitation of shoulder
injuries. They are felt to be preferable to other exercise programs in
that they simulate normal physiologic and biomechanical functions, create
little shear stress across injured or healing joints, and reproduce
proprioceptive stimuli. Because of these advantages, they may be used
early in rehabilitation and have been integral parts of "accelerated"
rehabilitation programs. The authors review the important components of a
closed-chain rehabilitation program and provide examples of specific
exercises that are used for rehabilitation of knee and shoulder injuries.
[References: 26]
<36>
Unique Identifier
7493216
Medline Identifier
96067368
Authors
Hurley BF.
Institution
Department of Kinesiology, College of Health and Human Performance,
University of Maryland, College Park, USA.
Title
Age, gender, and muscular strength. [Review] [50 refs]
Source
Journals of Gerontology Series A-Biological Sciences & Medical
Sciences. 50 Spec No:41-4, 1995 Nov.
Abstract
Muscular strength can be measured by cable tensiometry, non-motorized
dynamometry (e.g., handgrip dynamometer), motorized dynamometry, or with
free weights or exercise machines. Advantages and disadvantages of each
are discussed. Cross-sectional studies indicate that isometric and
concentric strength levels peak between the second and third decade,
remain unchanged until the fourth or fifth decade, and start to decline
from about the fifth decade at a rate of 12% to 15% per decade until the
eighth decade in men. Greater strength losses in both men and women have
been suggested from the few longitudinal studies available on this topic.
However, concentric strength levels in women tend to peak sooner, start
to decline earlier, and decrease at a slightly slower rate than men. Ageand inactivity-induced sarcopenia explains some but not all of the losses
in strength with age. There is a need to determine the separate roles of
disease, inactivity, and normal aging on these losses. New findings from
the Baltimore Longitudinal Study of Aging suggest a preservation of
eccentric strength levels with age in women. [References: 50]
<37>
Unique Identifier
7493224
Medline Identifier
96067375
Authors
Kenney WL. Buskirk ER.
Institution
Noll Physiological Research Center, Pennsylvania State University, USA.
Title
Functional consequences of sarcopenia: effects on thermoregulation.
[Review] [73 refs]
Source
Journals of Gerontology Series A-Biological Sciences & Medical
Sciences. 50 Spec No:78-85, 1995 Nov.
Abstract
The loss of skeletal muscle mass with aging (sarcopenia), and related
changes in body size and composition, may impact body temperature and
thermoregulation in both hot and cold environmental conditions.
Sarcopenia alters the thermal properties of the body as a passive system
because of differences in water content, and thus specific heat, of
muscle and adipose tissue. With respect to active thermoregulation in
warm environments, differences in fat-free weight (FFW) can explain more
than 80% of the variance in absolute blood volume (BV) among individuals
(Allen et al., 1956) and BV, in turn, profoundly influences the
cardiovascular responses to exercise and heat stress. For example, a
lower BV for a given body weight may explain more than half of the
variability in maximal oxygen uptake (VO2max). Thus, as VO2max declines,
any absolute task represents a higher relative VO2max (% VO2max) and
proportionately greater cardiovascular strain. Because BV is an important
determinant of left-ventricular filling pressure, and because older
individuals rely more on the Frank-Starling mechanism to increase cardiac
output (Q), a lower BV may also be associated with an inability to
increase Q appropriately. These effects are particularly important under
conditions of heat stress, where a larger increase in Q is necessary to
perfuse both skin and active muscle vascular beds. With exposure to cold,
age-related changes in body composition affect the insulation provided by
the peripheral tissues, especially in the limbs. This results in an
increased reliance on peripheral vasoconstriction to minimize heat loss,
yet this vasoconstriction is attenuated in older individuals.(ABSTRACT
TRUNCATED AT 250 WORDS) [References: 73]
<38>
Unique Identifier
11581553
Medline Identifier
21465113
Authors
Blazevich AJ. Giorgi A.
Institution
Department of Sport Sciences, Brunel University, Osterley Campus,
Isleworth, Middlesex TW7 5DU, United Kingdom.
anthony.blazevich@brunel.ac.uk
Title
Effect of testosterone administration and weight training on muscle
architecture.
Source
Medicine & Science in Sports & Exercise. 33(10):1688-93, 2001 Oct.
Abstract
PURPOSE: The purpose of this study was to assess muscle architecture
changes in subjects who were administered supraphysiologic doses of
testosterone enanthate (TE) and concurrently performed heavy resistance
training. METHODS: Ten subjects were randomly selected from the 21
subjects who participated in a previously published study (12). Subjects
were allocated to one of two groups as per Giorgi et al. (12) and
received either a saline-based placebo (nonTE) or a 3.5-mg.kg-1 body
weight dose of TE by deep intramuscular injection once a week for 12 wk.
Subjects also performed heavy resistance training using exercises that
targeted the triceps brachii muscle. Before and after the training
period, free-weight one-repetition-maximum (1-RM) bench press strength
was tested, muscle thickness and pennation of the triceps brachii
lateralis were measured using ultrasound imaging, and fascicle length was
estimated from ultrasound photographs. RESULTS: There were no significant
between-group differences in muscle thickness changes despite a trend
toward increased thickness in TE subjects (TE, 23.5%, vs nonTE, 13.8%).
However, 1-RM bench press performance and muscle pennation increased
significantly in TE subjects compared with nonTE subjects (P < 0.05).
There was also a trend toward longer fascicle lengths in the muscles of
nonTE subjects. CONCLUSION: The results of the present study suggest that
the use of TE in conjunction with heavy resistance training is associated
with muscle architecture changes that are commonly associated with highforce production. Since there was little difference between the groups in
muscle thickness, changes in pennation and possibly fascicle length may
have contributed to strength gains seen in TE subjects.
<39>
Unique Identifier
11445752
Medline Identifier
21338889
Authors
Osternig LR. Ferber R. Mercer J. Davis H.
Institution
Department of Exercise and Movement Science, University of Oregon,
Eugene, OR 97403, USA. louiso@oregon.uoregon.edu
Title
Effects of position and speed on joint torques and knee shear after ACL
injury.
Source
Medicine & Science in Sports & Exercise. 33(7):1073-80, 2001 Jul.
Abstract
PURPOSE: The purpose of this study was to assess the effect of joint
position and movement speed on hip (HT) and knee (KT) extensor torque,
HT/KT ratio (HKR), and anterior tibial shear (S) in presurgical-ACL
deficient (PRE; N = 15), post-ACL reconstructed (POST; N = 15), and
uninjured controls (CON; N = 15). METHODS: Measurements were recorded on
a semirecumbent variable resistance, closed-chain dynamometer. Tests were
conducted at 1 and 1.5 Hz and maximum speed at 33% and 50% 1RM. HT, KT,
and S were recorded during the extension phase of the cycle (85 degrees 25 degrees of knee flexion). RESULTS: KT was greatest when the knee was
more flexed, whereas HT dominated when it was more extended. This
suggests that the hamstrings, as a component of the hip extensors, may
generate considerable propulsive force during knee extension, which may
help counter anterior tibial shear. S increased whereas KT decreased,
suggesting that the quadriceps continue to generate shear force despite
the decreasing mechanical advantage producing KT. Increasing knee
extension speed significantly decreased S in the POST and CON groups. The
correlations between KT and S changed from significantly negative to
significantly positive as the knee extended from 85 degrees to 25 degrees
in the POST and CON groups. This may be related to the orientation of the
patellar tendon, relative to the tibial longitudinal axis that shifts
from a posterior to anterior direction, as the knee extends. CONCLUSIONS:
Joint position and movement speeds affect the magnitude of hip and knee
torques and anterior tibial shear. Reducing the magnitude of S during
heavy loads may be a normal phenomenon, and POST surgical subjects may
retain or regain this function by 1 yr after surgery.
<40>
Unique Identifier
10862549
Medline Identifier
20318212
Authors
Mazzetti SA. Kraemer WJ. Volek JS. Duncan ND. Ratamess NA. Gomez
AL. Newton RU. Hakkinen K. Fleck SJ.
Institution
The Human Performance Laboratory, Ball State University, Muncie, IN
47306, USA.
Title
The influence of direct supervision of resistance training on strength
performance.
Source
Medicine & Science in Sports & Exercise. 32(6):1175-84, 2000 Jun.
Abstract
PURPOSE: The purpose of this study was to compare changes in maximal
strength, power, and muscular endurance after 12 wk of periodized heavyresistance training directly supervised by a personal trainer (SUP)
versus unsupervised training (UNSUP). METHODS: Twenty moderately trained
men aged 24.6 +/- 1.0 yr (mean +/- SE) were randomly assigned to either
the SUP group (N = 10) or the UNSUP group (N = 8). Both groups performed
identical linear periodized resistance training programs consisting of
preparatory (10-12 repetitions maximum (RM)), hypertrophy (8 to 10-RM),
strength (5 to 8-RM), and peaking phases (3 to 6-RM) using free-weight
and variable-resistance machine exercises. Subjects were tested for
maximal squat and bench press strength (1-RM), squat jump power output,
bench press muscular endurance, and body composition at week 0 and after
12 wk of training. RESULTS: Mean training loads (kg per set) per week
were significantly (P < 0.05) greater in the SUP group than the UNSUP
group at weeks 7 through 11 for the squat, and weeks 3 and 7 through 12
for the bench press exercises. The rates of increase (slope) of squat and
bench press kg per set were significantly greater in the SUP group.
Maximal squat and bench press strength were significantly greater at week
12 in the SUP group. Squat and bench press 1-RM, and mean and peak power
output increased significantly after training in both groups. Relative
local muscular endurance (80% of 1-RM) was not compromised in either
group despite significantly greater loads utilized in bench press
muscular endurance testing after training. Body mass, fat mass, and fatfree mass increased significantly after training in the SUP group.
CONCLUSION: Directly supervised, heavy-resistance training in moderately
trained men resulted in a greater rate of training load increase and
magnitude which resulted in greater maximal strength gains compared with
unsupervised training.
<41>
Unique Identifier
11528347
Medline Identifier
21419587
Authors
Adams KJ. Swank AM. Berning JM. Sevene-Adams PG. Barnard KL.
Shimp-Bowerman J.
Institution
Exercise Physiology Lab, University of Louisville, Louisville, KY
40292, USA. kent@louisville.edu
Title
Progressive strength training in sedentary, older African American
women.
Source
Medicine & Science in Sports & Exercise. 33(9):1567-76, 2001 Sep.
Abstract
PURPOSE: This study investigated effects of an 8-wk, low-frequency and
low-volume, supervised, progressive strength training program emphasizing
free weight, multijoint movements on the muscular power, strength,
endurance, and flexibility of African American women 44 to 68 yr of age.
METHODS: Nineteen sedentary African American women were randomly assigned
to a strength training (ST) only group (N = 12; mean age, 51 yr) or a
nonexercise control (C) group (N = 7; mean age, 52 yr). Maximal power,
strength, absolute endurance, and flexibility were assessed before and
after training. Subjects trained 2 d x wk(-1) using free weight (barbells
and dumbbells) and machine (plate loaded) exercises for two to three sets
of 8 to 10 repetitions on both primary and assistance exercises. RESULTS:
Upper body power (medicine ball put distance) significantly increased
statistically (P = 0.002), but gains possibly lacked practical
significance because of measurement variation. Lower body power (peak
watts on bicycle) experienced a small, nonsignificant increase in the ST
group. Significant increases (P = 0.000) in 1RM muscle strength occurred
in the ST group (leg press, +99.8%; bench press, +34.4%). Absolute
endurance significantly increased (P = 0.000) in the ST group (leg press
repetitions to failure at 70% pretest 1RM, +221%; bench press repetitions
to failure at 50% pretest 1RM, +112%). Significant flexibility gains
occurred in the ST group (sit-and-reach test, +8.2%; P = 0.017). No
significant changes occurred in power, strength, absolute endurance, or
flexibility in the C group. CONCLUSION: This study demonstrates that 8 wk
of low-frequency, supervised, progressive strength training emphasizing
free weight, multijoint movements can safely cause significant gains in
muscle strength, absolute endurance, and flexibility in older African
American women.
<42>
Unique Identifier
11194105
Medline Identifier
21034542
Authors
Dolny DG. Collins MG. Wilson T. Germann ML. Davis HP.
Institution
Human Performance Laboratory, University of Idaho, Moscow 83844, USA.
ddolny@uidaho.edu
Title
Validity of lower extremity strength and power utilizing a new closed
chain dynamometer.
Source
Medicine & Science in Sports & Exercise. 33(1):171-5, 2001 Jan.
Abstract
PURPOSE: The purpose of this study was to compare selected variables
measured on a traditional isokinetic dynamometer (Cybex II) with a new
lower extremity, closed chain dynamometer (Omnikinetic, OmK). METHODS:
Twelve subjects (6 male, 6 female, age = 28+/-5 yr, mean +/- SD)
performed Cybex II knee flexion and extension at 1.05, 3.14, and 5.23 rad
x s(-1). A maximal effort of 10 repetitions of lower extremity concentric
extension and eccentric flexion at 36% of subject's 1-RM was performed on
the OmK. Crank power and joint (ankle, knee, and hip) kinetics were
recorded as a mean of 10 repetitions. RESULTS: t-Tests revealed right
versus left leg differences (P < 0.05) for Cybex II peak torque flexion
at 5.23 rad x s(-1), and OmK knee and hip peak power and hip root mean
square power (RMS) power. Cybex peak knee torques were related (Pearson r
values 0.78-0.92, P < 0.01) to OmK peak knee torques. Cybex average power
was related to OmK knee power (Pearson r values 0.71-0.96, P < 0.01) and
OmK crank power (r = 0.62-0.94, P < .01). Correlations tended to be
stronger comparing the OmK with the fastest (5.23 rad x s(-1)) Cybex II
speed. CONCLUSIONS: These results suggest that the OmK knee and crank
kinetic data are comparable to Cybex It isokinetic dynamometry. The
ability to evaluate lower extremity joint exercise at a subject's maximal
movement speed, in addition to the use of a closed-chain, multi-joint
motion, may allow for the OmK to provide a more global evaluation of
lower extremity kinetics during seated concentric-extension, eccentricflexion exercise.
<43>
Unique Identifier
11581557
Medline Identifier
21465117
Authors
Matheson JW. Kernozek TW. Fater DC. Davies GJ.
Institution
Program in Physical Therapy, Health Science Center, University of
Wisconsin-La Crosse, La Crosse, WI 54601, USA. montana@fflax.net
Title
Electromyographic activity and applied load during seated quadriceps
exercises.
Source
Medicine & Science in Sports & Exercise. 33(10):1713-25, 2001 Oct.
Abstract
PURPOSE: The aim of this study was to quantify and compare mean
quadriceps muscle activity and applied load for eight seated quadriceps
exercises using four types of resistance. METHODS: Using surface
electromyography (EMG), the right rectus femoris (RF), vastus lateralis
(VL), and vastus medialis oblique (VMO) muscles of 52 university students
aged 23.5 +/- 3.4 yr (35 female and 17 male subjects) were examined
during the exercises. Resistance devices included an ankle weight (78 N),
blue Thera-Band tubing, a Cybex 340 isokinetic dynamometer, and an
Inertial Exercise Trainer (IET). Electrogoniometer data were collected to
determine the range of motion (ROM), angular velocity, and phase
(concentric/eccentric) of exercise. Load cell data were analyzed to
determine tubing and IET applied loads during exercise. A within-subjects
criterion was used to improve intrasubject EMG reliability. All EMG
values were normalized to a 100% maximum voluntary isometric contraction.
Repeated measures ANOVAs with Bonferroni comparisons were used for
statistical analysis. RESULTS: Within-subject effects of muscle and
exercise were significant (P < 0.05) for both the concentric and
eccentric muscle activity. The interaction effect of mean average EMG
amplitude across exercises for the concentric phases of knee extension
was significant (P = 0.001). No significant interactions were found for
the eccentric phases of all seated quadriceps exercises. None of the
exercises selectively isolated the VMO over the VL; however, the VMO/VL
ratio was less (P < 0.05) during the concentric phases of the free weight
and elastic tubing exercise when compared with the others. Eccentric
phase VMO/VL ratios revealed that inertial resistance elicited greater
muscle activity than other forms of resistance exercise. CONCLUSION:
These findings suggest clinicians should consider biomechanical and
resistance data when developing a strengthening program for the
quadriceps muscle. Some seated quadriceps exercises may be more
appropriate for certain rehabilitation goals than others.
<44>
Unique Identifier
10862549
Medline Identifier
20318212
Authors
Mazzetti SA. Kraemer WJ. Volek JS. Duncan ND. Ratamess NA. Gomez
AL. Newton RU. Hakkinen K. Fleck SJ.
Institution
The Human Performance Laboratory, Ball State University, Muncie, IN
47306, USA.
Title
The influence of direct supervision of resistance training on strength
performance.
Source
Medicine & Science in Sports & Exercise. 32(6):1175-84, 2000 Jun.
Abstract
PURPOSE: The purpose of this study was to compare changes in maximal
strength, power, and muscular endurance after 12 wk of periodized heavyresistance training directly supervised by a personal trainer (SUP)
versus unsupervised training (UNSUP). METHODS: Twenty moderately trained
men aged 24.6 +/- 1.0 yr (mean +/- SE) were randomly assigned to either
the SUP group (N = 10) or the UNSUP group (N = 8). Both groups performed
identical linear periodized resistance training programs consisting of
preparatory (10-12 repetitions maximum (RM)), hypertrophy (8 to 10-RM),
strength (5 to 8-RM), and peaking phases (3 to 6-RM) using free-weight
and variable-resistance machine exercises. Subjects were tested for
maximal squat and bench press strength (1-RM), squat jump power output,
bench press muscular endurance, and body composition at week 0 and after
12 wk of training. RESULTS: Mean training loads (kg per set) per week
were significantly (P < 0.05) greater in the SUP group than the UNSUP
group at weeks 7 through 11 for the squat, and weeks 3 and 7 through 12
for the bench press exercises. The rates of increase (slope) of squat and
bench press kg per set were significantly greater in the SUP group.
Maximal squat and bench press strength were significantly greater at week
12 in the SUP group. Squat and bench press 1-RM, and mean and peak power
output increased significantly after training in both groups. Relative
local muscular endurance (80% of 1-RM) was not compromised in either
group despite significantly greater loads utilized in bench press
muscular endurance testing after training. Body mass, fat mass, and fatfree mass increased significantly after training in the SUP group.
CONCLUSION: Directly supervised, heavy-resistance training in moderately
trained men resulted in a greater rate of training load increase and
magnitude which resulted in greater maximal strength gains compared with
unsupervised training.
<45>
Unique Identifier
10978853
Medline Identifier
20435536
Authors
Panton LB. Rathmacher JA. Baier S. Nissen S.
Institution
Department of Education, East Tennessee State University, Johnson City,
Tennessee 37614, USA. panton@etsu-tn.edu
Title
Nutritional supplementation of the leucine metabolite beta-hydroxybeta-methylbutyrate (hmb) during resistance training.
Source
Nutrition. 16(9):734-9, 2000 Sep.
Abstract
The effects of supplementation of the leucine metabolite beta-hydroxybeta-methylbutyrate (HMB) were examined in a resistance training study.
Thirty-nine men and 36 women between the ages of 20-40 y were randomized
to either a placebo (P) supplemented or HMB supplemented (3.0 g HMB/d)
group in two gender cohorts. All subjects trained three times per week
for 4 wk. In the HMB group, plasma creatine phosphokinase levels tended
to be suppressed compared to the placebo group following the 4 wk of
resistance training (HMB:174. 4 +/- 26.8 to 173.5 +/- 17.0 U/L; P:155.0
+/- 20.8 to 195.2 +/- 23.5 U/L). There were no significant differences in
strength gains based on prior training status or gender with HMB
supplementation. The HMB group had a greater increase in upper body
strength than the placebo group (HMB:7.5 +/- 0.6 kg; P:5.2 +/- 0.6 kg; P
= 0.008). The HMB groups increased fat-free weight by 1.4 +/- 0.2 kg and
decreased percent fat by 1.1% +/- 0.2% while the placebo groups increased
fat-free weight by 0.9 +/- 0.2 kg and decreased percent fat by 0.5% +/0.2% (fat-free weight P = 0.08, percent fat P = 0.08, HMB compared to
placebo). In summary, this is the first short-term study to investigate
the roles of gender and training status on the effects of HMB
supplementation on strength and body composition. This study showed,
regardless of gender or training status, HMB may increase upper body
strength and minimize muscle damage when combined with an exercise
program.
<46>
Unique Identifier
11888148
Medline Identifier
21884991
Authors
Kibler W B. McMullen J. Uhl T.
Institution
Lexington Sports Medicine Center, University of Kentucky, USA.
Title
Shoulder rehabilitation strategies, guidelines, and practice. [Review]
[39 refs]
Source
Orthopedic Clinics of North America. 32(3):527-38, 2001 Jul.
Abstract
This framework for rehabilitation is consistent with the proximal-todistal kinetic chain biomechanical model and applies current concepts of
motor control and closed chain exercises. This framework approaches the
final goal--glenohumeral motion and function-through facilitation by
scapular control, and scapular control through facilitation by hip and
trunk activation. This article supplies guidelines for rehabilitation and
practices to implement the guidelines that have proved effective in our
hands. Other protocols may be effective, as long as they adhere to
several basic concepts of kinetic chain-based shoulder rehabilitation: 1.
Functional shoulder rehabilitation requires that the muscle activations
and joint motions follow a proximal-to-distal pathway along the
appropriate kinetic chain. 2. Muscles around the shoulder function in an
integrated fashion and should be rehabilitated in integrated patterns.
Specific muscles may need isolated activation, but this activation should
be facilitated by placing the proximal segments in a facilitating
function. 3. Scapular control and coupled rotator cuff activation is
vital to normal shoulder function. 4. Closed chain axial loading
exercises are the primary means of early shoulder rehabilitation and are
the mainstays of functional rehabilitation protocols. [References: 39]
<47>
Unique Identifier
10810766
Medline Identifier
20271063
Authors
Kibler WB.
Institution
Lexington Sports Medicine Center, Kentucky, USA.
Title
Closed kinetic chain rehabilitation for sports injuries. [Review] [33
refs]
Source
Physical Medicine & Rehabilitation Clinics of North America.
11(2):369-84, 2000 May.
Abstract
Closed chain techniques can increase the effectiveness of
rehabilitation protocols because they allow more normal physiologic
activations and biomechanical motions, especially in the early
rehabilitation phase. They have been shown to be effective in knee/leg
rehabilitation, but are also useful in shoulder/scapula rehabilitation.
Facilitation patterns allow muscles to be activated in normal sequences,
but also allow them to be isolated to recover their normal strength.
Closed chain exercises are an integral part of accelerated rehabilitation
programs. [References: 33]
<48>
Unique Identifier
10842410
Medline Identifier
20303052
Authors
Yeung SS. Ng GY.
Institution
Department of Rehabilitation Sciences, The Hong Kong Polytechnic
University, Hung Hom, Kowloon, Hong Kong.
Title
Effects of squat lift training and free weight muscle training on
maximum lifting load and isolinetic peak torque of young adults without
impairments.
Source
Physical Therapy. 80(6):570-7, 2000 Jun.
Abstract
BACKGROUND AND PURPOSE: Manual lifting is a frequent cause of back
injury, and there is no evidence as to which training mode can provide
the best training effect for lifting performance and muscle force. The
purpose of this study was to examine the effects of a squat lift training
and a free weight muscle training program on the maximum lifting load and
isokinetic peak torque in subjects without known neuromuscular or
musculoskeletal impairments. SUBJECTS: Thirty-six adults (20 male, 16
female) without known neuromuscular or musculoskeletal impairments
participated. The subjects' mean age was 21.25 years (SD=1.16, range=2024). METHODS: Subjects were divided into 3 groups. Subjects in group 1
(n=12) performed squat lift training. Subjects in group 2 (n=12)
participated in free weight resistance training of their shoulder
abductors, elbow flexors, knee extensors and trunk extensors. Subjects in
group 3 (n=12) served as controls. The maximum lifting load and
isokinetic peak torques of the trunk extensors, knee extensors, elbow
flexors, and shoulder abductors of each subject were measured before and
after the study. Training was conducted on alternate days for 4 weeks,
with an initial load of 80% of each subject's maximum capacity and with
the load increased by 5% weekly. RESULTS: All groups were comparable for
all measured variables before the study. After 4 weeks, subjects in
groups 1 and 2 demonstrated more improvement in maximum lifting load and
isokinetic peak torque of the back extensors compared with the subjects
in group 3, but the 2 training groups were not different. CONCLUSION AND
DISCUSSION: The findings demonstrate that both squat lift and free weight
resistance training are equally effective in improving the lifting load
and isokinetic back extension performance of individuals without
impairments.
<49>
Unique Identifier
8091049
Medline Identifier
94377798
Authors
Paletta GA. Warren RF.
Institution
Hospital for Special Surgery, New York, New York.
Title
Knee injuries and Alpine skiing. Treatment and rehabilitation. [Review]
[92 refs]
Source
Sports Medicine. 17(6):411-23, 1994 Jun.
Abstract
Alpine skiing is an increasingly popular recreational sport worldwide.
While the overall injury rate has declined and the pattern of injury
changed over the years, the incidence of knee injuries has not changed
substantially and accounts for 20 to 30% of all alpine skiing injuries.
Medial collateral ligament (MCL) injuries are the most common in skiing,
accounting for 15 to 20% of all skiing injuries and 60% of knee injuries
in skiers. Tears are commonly isolated, but may occur in association with
other ligamentous injuries. Associated meniscal pathology is rare.
Isolated MCL injuries are treated nonoperatively with a programme of
initial immobilisation, early range-of-motion, and isometric quadriceps
strengthening exercises. When full range of motion is achieved, a
programme of progressive resistance exercises, isokinetic and closed
chain exercises, and functional rehabilitation is instituted. Good
results with return to skiing can be expected in most cases. Isolated
lateral collateral ligament (LCL) injuries are rare in skiers. There is
usually associated cruciate or arcuate ligament complex. Careful physical
examination is essential to rule out associated ligament injuries and
more complex instability patterns. In the rare case of isolated LCL
injury, a similar approach to isolated MCL injury should be instituted.
Anterior cruciate ligament (ACL) injuries have become increasingly common
in skiers. This may reflect a true increase in the incidence or an
improved awareness and ability to diagnose ACL injury. Physical
examination and arthrometric analysis are important in assessing the
integrity of the ACL. Radiographic and magnetic resonance imaging (MRI)
evaluation may be helpful in assessing associated meniscal pathology.
Treatment of the ACL-deficient knee is usually surgical. However, prior
to reconstruction, a programme aimed at reducing effusion and regaining a
full, pain-free range of motion is recommended. Surgical reconstruction
is usually with the central third of the patella tendon using a bonetendon-bone autograft. Postoperative rehabilitation employs a functional
staged approach, requiring vigilant supervision by the surgeon. Isolated
posterior cruciate ligament (PCL) injury is rare in skiing, constituting
less than 1% of all knee injuries in most series. Careful physical
examination must be employed to rule out associated arcuate ligament
complex injury and more complex patterns of instability. Most isolated
PCL injuries are treated nonoperatively with a programme of initial
immobilisation in extension, ice, protected weight-bearing, early rangeof-motion exercises and progressive isometric strengthening.(ABSTRACT
TRUNCATED AT 400 WORDS) [References: 92]
<50>
Unique Identifier
8356377
Medline Identifier
93361887
Authors
Mazur LJ. Yetman RJ. Risser WL.
Institution
Department of Pediatrics, University of Texas-Houston Health Science
Center.
Title
Weight-training injuries. Common injuries and preventative methods.
[Review] [29 refs]
Source
Sports Medicine. 16(1):57-63, 1993 Jul.
Abstract
The use of weights is an increasingly popular conditioning technique,
competitive sport and recreational activity among children, adolescents
and young adults. Weight-training can cause significant musculoskeletal
injuries such as fractures, dislocations, spondylolysis,
spondylolisthesis, intervertebral disk herniation, and meniscal injuries
of the knee. Although injuries can occur during the use of weight
machines, most apparently happen during the aggressive use of free
weights. Prepubescent and older athletes who are well trained and
supervised appear to have low injury rates in strength training
programmes. Good coaching and proper weightlifting techniques and other
injury prevention methods are likely to minimise the number of
musculoskeletal problems caused by weight-training. [References: 29]
<51>
Unique Identifier
1579776
Medline Identifier
92253908
Authors
Verrill D. Shoup E. McElveen G. Witt K. Bergey D.
Institution
Noninvasive Cardiac Laboratory, Mecklenburg Cardiovascular Consultants,
P.A., Charlotte, North Carolina.
Title
Resistive exercise training in cardiac patients. Recommendations.
[Review] [152 refs]
Source
Sports Medicine. 13(3):171-93, 1992 Mar.
Abstract
Resistive exercise training has recently gained popularity in
cardiopulmonary rehabilitation programmes. Improvement in muscular
strength is important to facilitate return to daily vocational and
recreational activities after a cardiac event. Resistive exercise has
been shown to be haemodynamically safe for selected individuals with
cardiovascular impairment, even at relatively high workloads. This form
of training may enhance muscular strength and endurance, body
composition, blood lipid and lipoprotein levels, and cardiovascular
endurance, although further research is needed in cardiac populations.
Patients should be clinically screened and perform a symptom-limited
maximal graded exercise test prior to resistive training. Patients who
have characteristics associated with an increased risk of cardiac event
during exercise should avoid heavy resistive training. Free weights, cuff
and hand weights, isotonic/isokinetic machines, elastics, and other
resistive modalities may be used for exercise of major muscle groups in
cardiopulmonary rehabilitation. Resistive training workloads may be
determined by gradual acclimatisation or 1 repetition maximum testing.
Heart rate, blood pressure, rate-pressure product and rating of perceived
exertion should be determined during lifting movements. Circuit weight-
training has been recommended and has been reported to improve strength,
lean body mass, self-efficacy, and may decrease risk factors for coronary
artery disease. Nonsustained isometric or combined dynamic/isometric
exercises have also been recommended for cardiac patients since many
vocations involve lifting/pushing movements or frequent isometric muscle
contraction. There appears to be considerable benefit and minimal risk of
resistive exercise training for patients with cardiovascular impairment.
This mode of exercise may allow patients to perform daily strength tasks
safely, more efficiently, and with greater self-confidence. [References:
152]
<52>
Unique Identifier
1763251
Medline Identifier
92108329
Authors
Frndak PA. Berasi CC.
Institution
Doctors Hospital, Columbus, Ohio.
Title
Rehabilitation concerns following anterior cruciate ligament
reconstruction. [Review] [56 refs]
Source
Sports Medicine. 12(5):338-46, 1991 Nov.
Abstract
Rehabilitation following anterior cruciate ligament reconstruction is a
subject of controversy in the orthopaedic and rehabilitation literature.
With an increasing number of these operations currently being performed
and with the advent of arthroscopically assisted ACL reconstruction over
the past several years, particular rehabilitation needs and problems have
been identified in association with these patients. Various authors have
stressed one or a combination of a few basic themes which outline the
basic rehabilitation concerns following ACL reconstruction. The most
fundamental concern is the need to initiate motion very soon after
surgery. Prolonged postoperative immobilisation is known to cause serious
complications after ACL reconstruction which can be avoided by early
motion. Positions or activities which may apply excessive stress to a
newly reconstructed ACL must also be considered. The amount of protection
required by the graft will vary depending upon the type of graft used and
the quality of fixation obtained intraoperatively. Most authors agree
that nonweightbearing, active resistive quadriceps exercises should be
avoided for an extended period, while closed chain exercises may be
initiated much earlier. Strength recovery is obviously important for the
quadriceps postoperatively, but maximal strength returns of all of the
muscles about the knee must be pursued. Hamstring strength is of
particular concern as this may provide an active support to the
reconstructed ACL. Sensory loss in the knee after ACL disruption should
also be addressed during rehabilitation, prior to a patient's return to
full athletic activity. Progressive neuromuscular re-education exercises
which rely on sensory input from intact pericapsular structures are
encouraged. A final concern is the role of bracing after ACL
reconstruction.(ABSTRACT TRUNCATED AT 250 WORDS) [References: 56]
<53>
Unique Identifier
2017606
Medline Identifier
91205161
Authors
Poehlman ET. Melby CL. Goran MI.
Institution
College of Medicine, Department of Medicine, University of Vermont,
Burlington.
Title
The impact of exercise and diet restriction on daily energy
expenditure. [Review] [95 refs]
Source
Sports Medicine. 11(2):78-101, 1991 Feb.
Abstract
In addition to the direct energy cost of physical activity, exercise
may influence resting energy expenditure in 3 ways: (a) a prolonged
increase in postexercise metabolic rate from an acute exercise challenge;
(b) a chronic increase in resting metabolic rate associated with exercise
training; and (c) a possible increase in energy expenditure during
nonexercising time. It seems apparent that the greater the exercise
perturbation, the greater the magnitude of the increase in postexercise
metabolic rate. An exercise prescription for the general population that
consists of exercise of low (less than 50% VO2max) or moderate intensity
(50 to 75% VO2max) does not appear to produce a prolonged elevation of
postexercise metabolic rate that would influence body-weight.
Inconsistent results have been found with respect to the effects of
exercise training and the trained state on resting metabolic rate.
Whereas some investigators have found a higher resting metabolic rate in
trained than untrained individuals and in individuals after an exercise
training programme, other investigators have found no chronic exercise
effect on resting metabolic rate. Differences in experimental design,
genetic variation and alterations in energy balance may contribute to the
discrepant findings among investigators. A relatively unexplored area
concerns the influence of exercise training on energy expenditure during
nonexercising time. It is presently unclear whether exercise training
increases or decreases the energy expenditure associated with spontaneous
or nonpurposeful physical activity which includes fidgeting, muscular
activity, etc. The doubly labelled water technique represents a
methodological advance in this area and permits the determination of
total daily energy expenditure. Concomitant with the determination of the
other components of daily energy expenditure (resting metabolic rate and
thermic effect of a meal), it will now be possible to examine the
adaptive changes in energy expenditure during nonexercising time. A
plethora of studies have examined the combined effects of diet and
exercise on body composition and resting metabolic rate. The hypothesis
is that combining diet and exercise will accelerate fat loss, preserve
fat-free weight and prevent or decelerate the decline in resting
metabolic rate more effectively than with diet restriction alone. The
optimal combination of diet and exercise, however, remains elusive. It
appears that the combination of a large quantity of aerobic exercise with
a very low calorie diet resulting in substantial loss of bodyweight may
actually accelerate the decline in resting metabolic rate. These findings
may cause us to re-examine the quantity of exercise and diet needed to
achieve optimal fat loss and preservation of resting metabolic rate.
[References: 95]