Sports Nutrition Research Update
2007
With Exercise Physiology and
General Studies with Practical Application
G. Douglas Andersen, DC, DACBSP, CCN
www.andersEnchiro.com
Nutrient Timing Study
• 17 males, aged 18-28 with 1 to 5 years of
lifting experience.
• No past or current steroid history.
• No supplements in 3 months prior to study.
• 8 weeks prior to trial, started 4d/wk study
workout.
Nutrient Timing Study
Continued
• Diets analyzed 8-12 weeks prior and during
the 10 week experiment.
• Normal food patterns were established prior to
and confirmed throughout.
• Whole body scans, muscle biopsies and 1 rep
max at the beginning and end.
• Every workout done with personal trainers
blinded to groups.
Nutrient Timing Study
Supplements
• Protein, carbohydrates, and creatine
monhydrate drink – 2 times daily on workout
days.
• Dosed by percent of body weight. For 80kg
(175lb) – 270 calories - 32gm. Protein, 34.4gm.
Carbs, & 5.6gm. Creatine.
• 1 group doses AM and PM on workout days.
• 1 group doses Pre and Post workout days.
• Both groups had the same workouts and
supplements on same days, at different times.
Nutrient Timing Study
Results
• Pre/Post vs. AM/PM – PP had greater gains in
strength, lean mass and muscle hypertrophy
than AMPM.*
• Pre/Post vs AM/PM – PP had higher muscle
Glycogen, total Creatine, and Phosphocreatine.
*Measured as contractile protein accural + Type Ila
& Type IIx fiber cross-sectional area.
Nutrient Timing Study
Conclusion
• Both groups had no dietary restrictions so they could eat
before and after workouts.
• Both groups had an established high protein diets,
(2gmkgbwd) took the same % of additional protein, yet
pre/post had greater contractile protein accrual.
• Both groups took the same carb and creatine percent,
yet pre/post had higher glycogen and creatine levels.
• ONLY DIFFERENCE WAS THE TIME OF DAY THAT
THEY TOOK THE SUPPLEMENTS.
Cribb, P.J, Hayes, A., Effects of Supplement Timing and Resistance – Exercise on Skeletal Muscle Hypertrophy.
Med.Sci.. Sp. Ex. 2006; 38, (.11) 1918-26
Whey Protein vs. Casein
• 13 resistance trained males (~26.5yrs) divided into teo
groups for 10 week double-blind study
• 3 day a week freeweight-based, compound exercise,
high intensity supervised workouts were followed by both
groups
• Subjects supplemented with either whey or casein
protein at 1.5gm/kg/bw/d divided into four 0.4gm/kg/bw
doses
• Products were ingested with breakfast, lunch, dinner,
and following workouts.
• Diets were unchanged (pre vs. during)
Whey Protein vs. Casein
Continued
Average strength (kg)
Exercise
Squat
Pre
Post
Whey (n=6)
80.2
155.5
Casein (n=7)
71.0
123.2
Bench
Pre
Post
84.0
132.0
87.0
105.5
Pull-down
Pre
Post
84.0
106.8
72.0
92.7
Cribb, P.J., Williams, A.D., et. al. The Effect of Whey Isolate and Resisitance Training on Strength, Body Composition
and Plasma Glutamine. Int.J.Sp.Nutr.Metab. 2006: (16) 494-509
Whey Protein vs. Soy Protein
• 27 subjects ~23yrs (18f, 6m) not exercising prior to the
study
• Double-blind divided into 3 groups for the 6 week trial
• Each group (6f, 2m) lifted weights 3x/wk for 3 weeks
prior to experiment to familiarize and condition
• Workout was supervised and followed in 3 on- 1 off
pattern for 6 weeks
• Supplements: whey protein, soy protein or maltodextrin.
Amount: 1.2gmkgbwd taken in three .4gmkg doses
(~28gm x 3)
Time: 30 min. before, 30 min. following workouts and at
bedtime.
Whey Protein vs. Soy Protein
Continued
Whey
+26.7
+8.2
24%
2.5
Soy
+23.7
+7.6
30%
1.7
Placebo
+14.1
+4.0
42%
0.3
Squat (kg)
Bench (kg)
Urinary (3-mh*)
Lean mass (kg)
*Urinary 3 methyl histidine (umol/kg lean tissue mass) an
indicator of protein catabolism
• Protein increased strength and lean mass vs. isocaloric
placebo with no difference between whey and soy
Candow, D.G., Burke, N.C., et. al. Effect of Whey and Soy Protein Supplementation Combined with Resistance
Training in Young Adults. Int.J.Sp.Nutr>Metab. 2006: (16) 233-244
HMB, KIC and DOM’S
• Beta hydroxy beta methylbutyrate (HMB) with
ketoisocaproic acid (KIC)
• HMB and KIC have been used to reduce muscle
damage and speed recovery following
resistance exercise.
• 8 males (~ 23 years) in a randomized crossover
design who were unaccustomed to eccentric
exercise
• 3 gm/d HMB plus 0.3 gm/d KIC or placebo for 14
days
• On day 15 eccentric exercise was performed
(dosing was continued through day 17)
HMB, KIC and DOM’S
Continued
Results:
There were no changes in delayed onset muscle
soreness, range of motion, plasma, creatinine
kinase activity, peak isometric torque, or peak
isokinetic torque.
Conclusion:
HMB and KIC were not effective in reducing the signs or
Symptoms of eccentrically induced muscle soreness.
Hewitt, J., Nunan, D., et al. HMB and KIC Supplementation Does Not Reduce Signs and Symptoms of Exercise
Induced Muscle Damage. Med Sci Sp Ex. 2006;38(5)S401:A2233.
Iron Levels and Mental
Acuity in Women
• 149 women (age 18-35) were tested for both iron levels
and cognitive function in preparation for the study
Results before intervention
• Subjects Iron levels: 42 were normal, 73 were low, 34
were deficient
• Cognitive Tasks: As iron declines so did task accuracy
• Processing Speed: Lower iron = slower processing
Iron Levels and Mental
Acuity in Women
Continued
• Subjects were divided into 2 groups, either
– 160 mg/d ferrous sulfate providing 60 mg of elemental iron
– Placebo
• Following 4 months of daily dosing the women were retested
Results Following Intervention
• Elevated serum ferritin levels were associated with improved
cognitive performance
• Elevated hemoglobin levels were associated with faster
processing speed
Murray-Kolb, L.E., Beard, J.L. Iron Treatment normalizes Cognitive Functioning in Young Women. Am J Clin Nutr.
2007;85(3):778-787.
Cherry Juice and DOM’s
• 14 males (22 yrs) randomized placebo cross over study
• 12 oz fresh cherry juice 2x / day or placebo for 8 days.
16 days later procedure was repeated with opposite
drink.
Results
• In the 4 days following the exercise, mean strength loss
was 22% for placebo and 4% for cherry juice group.
• There was also less muscle soreness in the cherry juice
group
Connolly, D McHugh, M. Padilla-Zakour, o. “The efficiency of tart cherry juice blend in preventing the symptoms of
muscle damage” Br J Sports Med 2006; 6-21-06, pre print Epub
Echinacea Raises EPO But Not
Erythropoietic Status
•
24 M (~ 25 yr) divided into 2 groups - 8 gm daily of echinacea purpurea or placebo
Results:
Day
7
14
21
Serum EPO (mU/mL)
Echinacea
15.75
18.88
16.06
Placebo
10.01
11.02
9.20
There were no statistically significant increases in hematocrit, hemoglobin,
or red cell count despite positive trends.
•
•
Conclusion:
Echinacea significantly increased EPO but concomitant increases reaching
statistical and physiological significance in associated indices did not occur.
Therefore, this raises doubt to use echinacea to increase endogenous EPO
for purposes of enhanced athletic performance
Whitehead, MT The Effect of Four Weeks of Echinacea Supplementation on Erythropoietin and Indices of Erythropoietic Status Med Sci Sp Ex.
2006; 38(5)S407:A2256.
Chromium Picolinate
Fat Loss and Muscle Gain
• 86 F (19-50 yr) divided into 3 groups:
Group 1 – 200 mcg of chromium picolinate
Group 2 – Picolinate capsules
Group 3 – Placebo capsules
• Subjects ate the same low-calorie diets (3 meals + 1
snack were delivered daily)
• Trial period was 90 days
Chromium Picolinate
Fat Loss and Muscle Gain
Continued
Results:
Body Fat (%)
Lean Mass (%)
Cr pic
-2.1
+1.1
pic
-2.0
+1.2
placebo
-2.0
+1.2
Conclusion: No difference between chromium picolinate
and placebo regarding fat loss or muscle gain in women
who consumed the same low-calorie diet while maintaining
their pretrial activity levels.
Lukaski, H.C., Penland, J.G. No Effect of Chromium Picolinate Supplementation on Body Weight/Composition of
Women Fed Controlled Diets. Med Sci Sp Ex. 2006;38(5)S126:1122
Quercetin and Endurance
• A flavanoid found in onions, kale, apples and broccoli
• Typical US diet contains ~107mg/d
• Estimated intake of persons with the highest intake of
fruits and vegetables (90th percentile) ~225mg/d
• Quercetin is a powerful antioxidant (much stronger than
vitamin C) with high levels anticarcinogenic activity and
other properties including protection of proteins, DNA
and regulation of gene expression
• Studies on antioxidants and exercise are mixed with a
trend toward reducing muscle damage but seldom
showing improved performance.
Quercetin and Endurance
Continued
• 12 elite cyclists were recruited for a double-blind in
season study and had at least 1 race during the two 6
week legs of the trial
• 11 completed both legs that consisted of baseline week
3, 6, crossover and week 12 – 30km (18.6 miles) time
trials on an exercise bike
• Subjects drank 2/srv/d for 6 weeks of a product which
contained 150mg of vitamin C, 50mg of vitamin E,
300mg of green tea extract, 45mg caffeine, and small
amounts of B, B2, B6, and B12 per serving. The same
formula with 300mg of quercetin per serving was also
consumed 2x/d 6 wks.
• No changes were made to subjects diets, training or
racing schedules throughout the 12 week study.
Quercetin and Endurance
Continued
Results
30k time (min/sec)
Baseline
52:18
6 wks/sup
51:31
6 wks/sup+Q
50:42
Final 5K (min/sec)
Speed (km/hr)
Power (watts)
7:44
32.24
277
7:37
34.76
293
7:29
35.24
303
• No change in heart rate, VO2 max or perceived exertion
• Quercetin improved 30km time ~3.1% and final 5k ~2%
Macrae, H., Meffered, K. Dietary Antioxidant Supplementation Combined with Qeurcetin Improves Cycling Time Trial
Performance. Int.J.Sp.Nutr.Ex. Metab. 2006: (16) 405-419.
Testosterone, Ergogenesis and Detection
• 18 M (~ 25 yr) consented to a double-blind trial
• Subjects were match-paired for bench press, leg
press, and 10 second cycle sprints
• Random assignments of testosterone enanthate
3.5 mg/kg/bw or saline via IM injection once
weekly for 6 weeks
• 280 mg of testosterone per week for an 80 kg
(176 pound) subject
Testosterone, Ergogenesis and Detection
Continued
• All subjects were tested at baseline, week 3, and
week 6
• Week 3: single repetition bench press increased
9% in testosterone group, no change in placebo
group; cycle speed increased in testosterone
group
• Week 6: bench press increased 15% in
testosterone group, no change placebo; body
mass increased 7% in testosterone group, no
change placebo.
Testosterone, Ergogenesis and Detection
Continued
Laboratory Results:
T/E ratio of 4:1 from urine is currently the level used to
screen for anabolic steroid use.
– 9/9 in testosterone group had improved performance
– The T/E range in the 9 subjects was 2:1 to 37:1
– 4/9 in testosterone group had T/E ratio below 4:1
Conclusion:
4 of 9 subjects used testosterone for 6 weeks, yet did
not test above the allowable limit.
Deakin, G., Rogerson, S., et al. Performance Enhancement and Urinary Detection After Short-Term Testosterone
Enanthate Use. Med Sci Sp Ex. 2006;38(5)S405:A2249.
Creatine Use & Free Radicals
•
•
•
•
•
•
29 M (~ 17 yr) divided into 3 groups: creatine 10, placebo 10, control 9
32 days of either creatine or placebo supplementation while undergoing a
resistance training program
Pre and post testing included oxidative stress, total antioxidant status, uric
acid, and bench press maximum
Results:
Bench press increase averaged 10 kg (22 lb) in creatine group compared to
placebo or control
Total antioxidant status decreased in creatine group 1.11 vs 0.6 mmol/l in
placebo
Conclusion:
Strength gains caused by creatine may tax antioxidant system by enhancing
the ability to perform work thus exceeding reserves
Conte, M., Percario, S., et al. Increase of Free Radical Production in Athletes Undergone Creatine Supplementation and Resistance Training.
Med Sci Sp Ex. 2006;38(5)S405:A2250
Amino Acid Muscle Uptake
• 9 seniors (5 F, 4 M; ~ 68 years) ingested 7gm of
essential amino acids
• 10 seniors (3 F, 7 M; ~ 67 years) ingested 15gm
of whey protein which also contained 7gm of
essential amino acids.
• Phenylalanine was measured before and 3.5
hours following ingestion via leg muscle biopsy
and femoral arteriovenous blood draw
Amino Acid Muscle Uptake
Continued
Test
Whey
EAAs
Phenylalanine
uptake*
23 mg (±5)
10 mg (±4)
Fractional
synthetic rate**
0.029 h (±0.009)
0.008 h (±0.006)
*Blood **Biopsy
The whole whey protein increased protein synthesis more than it’s
essential amino acid content. Probably caused by greater insulin
response to ingestion.
Katsanos, C.S., Paddon-Jones, D., Zhang, X., et al. Muscle Protein Synthesis in the Elderly Following Ingestion of
Whey Protein or its Corresponding Essential Amino Acid Content. Med Sci Sp Ex. 2006;38(5)S112:A1061.
Intramuscular Buffering with Beta-Alanine
• Carnosine is a dipeptide synthesized from Histidine and
Beta-Alanine
• Beta-Alanine is the rate-limiting substrate in Carnosine
synthesis
• Beta-alanine ingestion will increase muscle Carnosine
levels
• 20 subjects (~ 25 years) took 2 weeks of Beta-Alanine or
placebo
• Dosed at 1.6 gm with ~ 50 gm carbohydrate 4x/d (6.4gm
total)
• Muscle endurance was measured by the time subjects
could maintain an isometric leg extension
Intramuscular Buffering with Beta-Alanine
Continued
Results:
Isometric Endurance Time
Test
Control Group
Beta-Alanine Group
Pre
Post
74.5 (±4) sec
73.8 (±3.5) sec
70 (±5) sec
78 (±3.3) sec
Researchers concluded the 11.4% increase in isometric
endurance was consistent with an increased intramuscular
buffering capacity supporting their previous work that pH
can limit exercise performance.
Harris, R.C., Hill, C.A., Sale, C., et al. Effect of 14 Days Beta-Alanine Supplementation on Isometric Endurance of the
Knee Extensors. Med Sci Sp Ex. 2006;38(5)S125:1119.
Taurine and Endurance
• Taurine is the second most abundant free amino acid in
muscle
• A common ingredient in energy drinks, made from
cysteine
• Best understood for its role in bile formation
• Possesses antioxidant, hypotensive, detoxifying
capabilities
• May slow the breakdown of hyaluronic acid
• Small studies show improved energy in congestive heart
failure patients
Taurine and Endurance
Continued
• 11 (~ 28 years) triathletes and cyclists did 3 separate trials
• 90 minute submaximal ride (65% VO2) followed by a time trial
• Subjects ingested each drink in random order: Crystal Light™
placebo, CL with 2000 mg taurine added, CL placebo #2 –
researchers falsely stated taurine was added (it was not).
Results:
No difference in time trial, 02 consumption, or CO2 production
Rutherford, J., Stellingwerff, T., Spriet, L.L. The Effect of Acute Taurine Ingestion on Endurance Performance in Well
Trained Cyclists. Med Sci Sp Ex. 2006;38(5)S127:A1124.
Branch Chain Amino Acids and Fatigue
• Central fatigue hypothesis contends that a high
tryptophan to BCAA ratio can contribute to fatigue
• 8 untrained men (30-48 yr) were tested on 2 occasions
• An exercise bike ride of 4 hours (or until exhaustion) at
50% VO2 max was performed and repeated 1 month
later
• 8 gm of branch chain amino acids in 1 liter of fluid or a
zero calorie placebo beverage was consumed
throughout the ride
Branch Chain Amino Acids and Fatigue
Continued
• Plasma BCAA concentration increased
when BCAAs were ingested
• Free tryptophan to BCAA ratio was
reduced
• There was no change in exercise time
• Subjective fatigue was lower with BCAAs
than placebo
Yoshida, M., Tanaka, H., et al. Effects of BCAA Supplementation on Plasma Amino Acids and Subjective Fatigue and
Muscle Soreness During Low-Intensity Prolonged Exercise. Med Sci Sp Ex. 2006;38(5)S404:A2246
Vitamin C and EIA
• 8 subjects with exercise-induced asthma (EIA) consented
to this trial
• 1500 mg of vitamin C or placebo was taken for 2 weeks
• Following a one-week washout, protocol was repeated
with the opposite treatment
• Procedure: pre and post-exercise pulmonary function
was evaluated, pre and post-exercise urine samples
were assayed for proinflammatory chemicals, and preand post-exercise exhaled breath nitric oxide was
measured
Vitamin C and EIA
Continued
Results:
Test
Vitamin C
Post exercise nitric oxide (ppb)
23.7
Post ex. leukotriene (ng/mmol/cr)
5.3
Post ex. prostaglandin F2 (ng/mmol/cr) 8.5
Post ex. hydrogen peroxide (mmol/L)
5.6
Placebo
34.1
11.1
13.0
12.6
Conclusion: In this trial vitamin C reduces severity of
exercise-induced asthma
Tecklenburg, S., Stager, J.M., et al. Ascorbic Acid Supplementation Reduces Severity of Exercise-Induced Asthma. Med
Sci Sp Ex. 2006;38(5)S382:2158.
Variability Of Sweat NA and Fluid Loss
Endurance Athletes
• 132 subjects (84 M, 48 F) ~ 39.5 years of age
• Exercise bike for 30 min at 70-75% of max heart
rate
• Sweat rate was calculated by weighing before
and after the workout
• Sodium loss was calculated by a chemical
analysis of absorbent patches worn on the
forearm and scapula
Variability Of Sweat NA and Fluid Loss
Endurance Athletes
Continued
Results:
• Sweat rate was 1.4 ± 0.5 l/hr
• Fluid coefficient of variation (CV) was approximately
34%
• Sweat sodium was 66.6 ± 40.7 mEq/hr (~ 1400 mg ±
900 mg)
• Sodium CV was 61%
Pahnke, M.D., Trinity, J.D., Coyle, E.F. Large Interindividual Variability in Sweat Sodium Loss in Well-Trained
Endurance Athletes. Med Sci Sp Ex. 2006;38(5)S218:A1509.
Variability Of Sweat NA and Fluid Loss
Professional Hockey Players
Game vs Practice
•
10 NHL players were weighed before and after a pre-season practice and a
pre-season game
• On both occasions they wore absorbent patches in order to calculate
sodium losses
Results:
• Total sweat losses in players were greater during the game: 3.71 ± 0.9 than
in practice, 2.6 ± 0.6
• Total sodium losses were greater during the game: 252 ± 104 vs 168 ± 118
mmol
(1 mmol/na = 23 mg/na)
Conclusion:
• Professional ice hockey players experience greater sweat and sodium
losses during games compared to practices.
• Sodium replacement may be necessary due to high sodium losses.
Comment: This study should be replicated with a larger sample size.
Godek, S.F., Godek, J., McCrossin, J., Bartolozzi, A. Sweat and Sodium Losses in Professional Ice Hockey Players
During a Pre-Season Practice and Game.
Sodium Loading
• 8 endurance trained males, (~36 yrs) doubleblind trial
• High vs. Low sodium beverage prior to a run to
exhaustion @ 70% VO2 max in 90 degree heat
with 50% relative humidity
• Repeated 2 weeks later with opposite treatment
• 65 minutes prior to the run, subjects drank 25
oz. in equal portions (3.5 oz. every 9 minutes)
• High sodium 164mmol Na/L
• Low sodium 10mmol Na/L
Sodium Loading
Continued
Times in minutes
Subject
1
2
3
4
5
6
7
8
Hi Na
49.1
82.2
85.2
136.3
59.0
59.3
70.0
37.4
Low Na_____
47.0
47.0
59.8
125.9
48.8
38.3
53.2
38.4
High Na increased plasma volume, decreased perceived exertion and
improved exercise capacity in the heat in 7/8 subjects.
Sims, S.T, Vliet, L., et. al. Sodium Loading Aids Fluid Blance and Reduces Physiological Strain of Trained Men
Exercising in the Het. Med.Sci.Sp.Ex. 2007; 39 (1) 123-130
Heat Impairs Exercise - Marathons
• Results of 7 annual marathons (# of yrs) – Boston (36),
New York (29), Twin Cities (22), Duluth (23), Richmond
(6), Hartford (12), and Vancouver (10) were analyzed for
times and temperatures by both gender and fitness level.
Findings:
Times were slower as temperatures increased. Men,
women, elites, and recreational runners were all affected
in a linear fashion. Slower runners had greater sensitivity
to heat than elites.
1Ely,
M R., Cheuvront, S.N., Roberts, W.O., Montain, S.J. Impact of Weather on Marathon Running Performance. Med
Sci Sp Ex. 2007;39(3)487-501.
Heat Impairs Exercise - Squash
• Squash players either 1) rested or 2) rested in cool water
for 60 min prior to intervention
• Intervention consisted of a simulated 60 min match
followed by skill tests in 82° weather
Results:
– Compared to rest only, the rest with whole body
precooling players had lower core temps, greater heat
storage, and lower heart rates throughout the workout
– Athletes who were precooled also had increased
target accuracy and reduced errors in the skill tests
which followed the 60 minute simulated match
Sherman, R. Batterham, A. Influence of Pre-Cooling on Skill Performance During Intermittent Exercise in the Heat. Med
Sci Sp Ex. 2006;38(5)S58:A824.
Patient Impression of Exercise Exertion
• 88 subjects age 27-30 (50 male, 38 female) were exercise
tested (based on 85% age-adjusted heart rate) and then
questioned about their effort
• 47% overestimated, 34% underestimated, 19% were accurate
when asked how hard they worked during the test.
• Gender breakdown revealed: 53% F, 42% M over-estimated,
18% F, 46% M underestimated
Comment:
Apparent unsuccessful office-designed programs need onfield observational confirmation.
Matthews III, M.L., Aaron, D.J., Jekal, Y., et al. Comparison of Predicted vs. Actual Rating of Perceived Exertion (RPE)
for a Submaximal Exercise Test. Med Sci Sp Ex. 2006;38(5)S79:A917
Effects of Dehydration on Basketball
• 8 elite males (17-22 yr) basketball players were
tested on 5 occasions
• In random order the tests performed were at 1%,
2%, 3%, and 4% dehydration and euhydrated
• Compared to the euhydrated state, as the
subjects’ fluid deficit increased, sprinting speed
and shooting accuracy decreased in a linear
fashion
Effects of Dehydration on Basketball
Continued
Baker, L.B., Doherty, K.A., Chow, M., Kenney, W.L. Progressive Dehydration Causes a Progressive Decline in Basketball
Performance in 17-22-Year-Old Men. Med Sci Sp Ex. 2006;38(5)S177:A1341.
Basketball, Fluids, and Performance
•
15 boys (12-15) played basketball 2¼ hours
on 3 occasions
•
The 3 trials were double blind and consisted
of drills to simulate a 4 quarter game
Each subject played:
1. Dehydrated 2%
2. Euhydrated with Gatorade
3. Euhydrated with a flavored placebo
Basketball, Fluids, and Performance
Continued
Results:
Dehydrated
Placebo Water
Gatorade
Shooting percent*
45%
53%
60%
Sprint Times**
40s
37s
35s
Lateral Movement
Times***
43s
41s
41s
*15 feet around the world, and free throws
**Suicide sprints times (seconds)
***10 width of court sprints (seconds)
Dougherty, K.A., Baker, L.B., Chow, M., et al. Two Percent Dehydration Impairs and Six Percent Carbohydrate Drink
Improves Boys Basketball Skills. Med Sci Sp Ex. 2006;38(9):1650-1658.
Added Protein to CHO Drink Aids Fluid
Retention
• 13 endurance trained subjects (5f, 8m) ~24 yrs
cycled in 3 counter-balanced, blinded tests
• Subjects rode to dehydration (-2.5% bw) at 80%
max heart rate in 77 degree heat.
• Fluid was replaced (+2.5% bw) during 20
minutes following ride
• Recovery was monitored for 3 hours
• Beverages were 6% CHO, 6% CHO+1.5% PRO,
or flavored water.
Added Protein to CHO Drink Aids Fluid
Retention
Continued
• Rehydration involves:
1. Gastric emptying
2. Intestinal absorption
3. System retention
Fluid Retention at 3 hours
Water
CHO
CHO+PRO
Total (mL)
880
1245
1519
Percent
53%
75%
88%
• Na dependant amino acid co-transporters differ from Na/dependant
glucose co-transporters
• Fluid retention is increased by activation of mutiple transporters
(provided osmolality of fluid is below 400mOsm/kg)
Seifert, J., Harmon, J., DeClercq, P. Protein Added to a Sports Drink Improves Fluid Retention. Int.J.Sp.Mutr.Metab.
2006: (16) 420-428
Added Protein to CHO Drink Benefits
Endurance Following Recovery
• Double-blind placebo crossover of 12 male cyclists
• Subjects performed a 2 hour ride at 70% VO2 max followed by a 30
minute timed trial, a 4 hour rest, a ride to fatigue at 85% VO2 max,
and one set of leg extensions to exhaustion
• Subjects consumed either a carbohydrate sports drink or the same
drink with added protein
Results
There was no difference in the 2 hour ride, the first timed trial, or leg
extensions to exhaustion. Adding protein increased the time to
fatigue following the 4 hour rest by 24%.
Millard-Stafford, M., Warren, G.L., Hitchcock, K.M., et al. Added Protein to Carbohydrate: No Acute Performance
Benefit but May Facilitate Subsequent Endurance Capacity. Med Sci Sp Ex. 2006;38(5)S113:1066.
1.8% Protein Added To CHO
Drink Improves Time to Exhaustion
• 38 cyclists were pooled from 3 previous studies
performed by the authors
• Subjects were tested with a 7.3% CHO drink or a 7.3%
CHO + 1.8% PRO (CHO-PRO)
• The data from rides to exhaustion at 75% VO2 max was
reanalyzed and averaged
Results averaged over 3 trials:
CHO-PRO time to exhaustion 1hr 56 min
CHO time to exhaustion 1 hr 37 min
Saunders, M.K., Todd, M.K., Valentine, R.J. Inter-Study Examination of Physiological Variables Associated with
Improved Endurance Performance with Carbohydrate/Protein Administration. Med Sci Sp Ex. 2006;38(5)S113:1067.
Protein Added to Sports Drink Improves
Time Trial Following Glycogen Depletion
• 8 triathletes (6 M, 2 F, ~ 21 years) performed two 2 hour
intense rides to deplete glycogen, 7 days apart in
random order
• Following each ride subjects drank approximately 16 oz
of a CHO-PRO or CHO beverage 3 times an hour for 2
hours
• A 10K time trial was performed
Results (Average time)
CHO-PRO - 9 min 31 sec
CHO - 9 min 40 sec
Kuro awa, Y., Kime, R., Murase, N., et al. Milk Peptide Intake Enhances Bicycle Exercise Performance After Exhaustive
Exercise. Med Sci Sp Ex. 2006;38(5)S125:1118.
No Difference: Sports Drink vs. Addition
of Protein
• 10 trained male cyclists (~ 24 years) performed 80K timed trials in
random order 7 days apart with 1 of 3 beverages:
– Placebo
– 6% CHO
– 6% CHO plus 1.8% PRO
• The beverages were consumed at a rate of ~ 8 oz every 15 min
Results
Timed trial average:
CHO – 2 hours 15 minutes
CHO-PRO – 2 hours 15 minutes
Placebo – 2 hours 21 minutes
Van Essen, M., Gibala, M.J. Failure of Protein to Improve Timed Trial Performance When Added to a Sports Drink. Med
Sci Sp Ex. 2006;38(8):1476-1483
Time to Exhaustion Improved With
Added Protein
• 14 cyclists performed 2 rides 1 day apart on 2
occasions ~ 10 days between tests
• Day 1 was a 70% VO2 max ride to exhaustion
• Day 2 was an 80% VO2 max ride to exhaustion
• Approximately every 15 min during the ride
subjects consumed either 9.3% CHO or 7.5%
CHO +1.8% PRO
• Creatine kinase was measured before and after
both rides
Time to Exhaustion Improved With Added Protein
Continued
Average Time to Exhaustion
VO2
CHO Time
CHO-PRO
70%
80%
1:35:48
42:18
1:38:06
42:54
Creatine Kinase U/L
Time
CHO
CHO-PRO
Pre
Post
202.6
582.0
187.5
272.9
Romano-Ely, B.C., Todd, M.K., Saunders, M.J., St. Laurent, T. Reduced Post Exercise Muscle Damage with CHO
PRO versus CHO. Med Sci Sp Ex. 2006;38(9):1608-1616.
Sports Drink Beats Added Protein In Time
Trial Following Endurance Exercise
•
10 cyclists rode for 2 hours followed by a
timed trial on 3 occasions
1. 6% CHO beverage
2. Placebo beverage
3. 6.6% CHO + 1.6% PRO
•
Rides were performed in a double-blind
placebo-controlled manner
Sports Drink Beats Added Protein In Time Trial
Following Endurance Exercise
Continued
Results
Timed trial times:
Drink
Time
6% CHO
37:24
CHO+PRO
39:12
Placebo
40:48
Osterberg, K.L., Zachwieja, J.J., Smith, J.E., Murray, R. Relative Benefits of Carbohydrate and Carbohydrate + Protein
for Cycling Time-Trial Performance. Med Sci Sp Ex. 2006;38(5)S189:1392.
CHO Beats PRO-CHO During Simulated
Football Game
• 18 college football players (~ 20 years)
completed simulated game-type activities over 2
halves with a 20-minute halftime 3 times, with
each treatment7 days apart
• Muscle power was assessed by jump and reach
tests
• At halftime subjects drank either an
unsweetened placebo beverage, 270 calories of
a CHO beverage, or 270 calories of a CHO-PRO
beverage with a CHO to PRO ratio of 3:1
Sports Drink Beats Added protein During
Simulated Football Game
Continued
Results
Beverage
CHO
Placebo
CHO-PRO
Jump Power (in watts)
1587.4
1582.5
1577.4
Crawford, G.E., Miller, G.S., Womack, J.W., Green, J.S. Effect of Carbohydrate and Carbohydrate-Protein
Supplementation on Power Performance in Collegiate Football Players. Med Sci Sp Ex. 2006;38(5)S340:A199
Added Protein vs. Two Sports Drinks
Reduces Post Exercise Muscle Damage
•
•
12 male cyclists (~ 20 years) performed 4 rides to
exhaustion at 75% VO2 max ~ 7 days apart in a
double-blind fashion using 1 of 4 beverages:
Beverages:
1. Placebo
2. 7.3% CHO
3. 9.1% CHO
4. 7.1% CHO + 1.8% PRO
Postexercise muscle damage 24 hours later was
1) measured by creatine plasma creatine kinase levels
2) tested by one set of single leg extensions (70%
1 RM) to exhaustion
Added Protein vs. Two Sports Drinks
Reduces Post Exercise Muscle Damage
Continued
Results
Treatment
Placebo
Hi CHO
Low CHO
CHO-PRO
Creatine
Kinase IU*
+194
+203
+224
-16
Leg Extension
(reps to exhaustion)
8.8
9.5
9.7
11.3
St. Laurent, Jr., T.G., Todd, M.K., Saunders, M.J. Carbohydrate-Protein Beverage Improves Muscle Damage and
Function Versus ISO carbohydrate and ISO Caloric Carbohydrate-Only Beverages. Med Sci Sp Ex.
2006;(38(5)S340:1993
Cholesterol and Recovery
• Blood cholesterol reduction appears ~ 2 hours after
eccentric resistance exercise and may remain decreased
for up to 2 days
• This observed decrease is theoretically due to postactivity membrane disruption allowing and/or attracting
cholesterol entry into the fatigued muscle cell.
• Lead author Steve Riechmans’ (PhD) team discovered
dietary cholesterol augments lean mass accrual
following resistance exercise.
Cholesterol and Recovery
Continued
• 8 men (~21 yrs.) performed 2 sets of ~100 eccentric
single leg extensions separated by 4 weeks
• Dietary cholesterol was limited to under 200mg/d for 4
weeks
• Subjects received either 3 whole eggs or 3 egg whites
mixed in a protein shake prior to the trial
• Strength and delayed onset muscle soreness were
measured at 1, 2 & 3 days after the eccentric exercise
test.
• Treatment was reversed and repeated 30 days later
Cholesterol and Recovery
Continued
Results:
Subjects who received the whole eggs (~900mg cholesterol) in the first
test had:
• 1. Greater strength loss at 1, 2, & 3 days post-exercise
• 2. More soreness at 1, 2 & 3 days post-exercise
• 3. Less muscle soreness after the second test (30 days)
• 4. More strength at 30 days
Conclusion:
Cholesterol increases the initial degree of post-exercise muscle
damage and appears to enhance long term recovery.
Riechman, S., Kean, D., et. al. Dietary Cholesterol Alters Recovery From Eccentric Muscle Damage In Humans. Med.Sci.Sp.Ex. 2006: 38 (5) 5386:A2172
C-Spine DJD – Who hurts?
• 50 (37m-23f) Healthy seniors x-rayed
• 52 (39m-23f) Seniors w/c-Spine s/s xrayed
• Both groups had similar levels of
significant DJD and spurring
• Healthy group history of more lifetime
exercise/activity than unhealthy
C-Spine DJD – Who hurts?
Continued
Pain-fee group characteristics (via x-ray)
• Little or no lordosis
• Kyphotic and/or linear alignment
• Males had 3.5mm canal diameters
• Females had 2.9mm canal diameters
• 60% show spontaneous fusion of vertebral
bodies & anterior longitudinal lig.
ossification
C-Spine DJD – Who hurts?
Continued
Unhealthy characteristics (via x-ray)
• Lordosis
• Hyperlordosis
• Smaller canal diameters
Matsunaga S. et al., The Roentgenographic Characteristics Of The Cervical Spine In Healthy Elders,
Presented At The
Annual Meeting Of The North American Spine Society, Seattle, 2006; as yet published.
Body Fat and Inflammation
• 444 teenagers, (13-18 yrs) 249 males and
195 females
• Tested for fitness, weighed, divided into
groups:
Normal weight fit, normal weight unfit,
overweight fit, overweight unfit
• C-reactive protein was tested
Warnberg, J., Ruiz, J.R., Sjostrom, M., et al. Association of Fitness and Fatness to Low-Grade Systemic Inflammation
in Adolescents. The AVENA Study. Med Sci Sp Ex. 2006;38(5)S8:A613.
Body Fat and Inflammation
Continued
Results
Group
Normal weight, fit
Normal weight, unfit
Overweight, fit
Overweight, unfit
Elevated CRP
23%
24%
50%
56%
Conclusion:
Weight gain leads to systemic inflammation
Effect of Time of Glycogen Replacing
Meals on Insulin
•
6 subjects were inactive and hypercaloric 48 hours prior to each of 4
conditions to decrease insulin sensitivity
Control
Pre-exercise meal
Post-exercise meal
3 hours post-exercise meal
•
Exercise was designed to deplete glycogen 30% (65 min ride + ten 30sec sprints)
•
12 hours after each meal insulin was measured via glucose infusion
Effect of Time of Glycogen Replacing
Meals on Insulin
Continued
12 hour postControl
prandial
glucose infusion
Insulin uU/ml
24.2
Pre-exercise
meal
19.8
Postexercise
meal
19.7
3 hours postexercise meal
18.8
Comment:
“There is no such thing as a bad time to exercise for
persons who want to increase insulin sensitivity.” (GDA)
Stephens, B.R., Sautter, J.M., Holtz, K.A., et al. The Influence of Meal Timing on Insulin Action Following Exercise.
Med Sci Sp Ex. 2006;38(5)S91:A967.
The Metabolic Changes Of Detraining In Fit
Young Women
• 16 F collegiate dancers (~ 20 yr)
• Measured at baseline and following an 8
week detraining period
Test
Tolerance
Fasting Cholesterol
BMI
Body Weight
*At 8 weeks
Change from Baseline* Glucose
N/C
N/C
N/C
N/C
The Metabolic Changes Of Detraining In Fit
Young Women
Continued
Test
Changes from Baseline_
Insulin Response to Glucose Challenge
↑↑
Fasting Free Fatty Acids
↑↑
Fasting Triglycerides
↑↑
Fasting Insulin
↑
Waist Size
↑
Waist to Hip Ratio
↑
Conclusion:
The markers of obesity development due to inactivity occur
prior to weight gain.
Hou, C.W., Lin, C.H., Kung, H.W. Effect of a 2-Month Detraining on Body Composition and Insulin Sensitivity in Young
Female Dancers. Med Sci Sp Ex. 2006;38(5)S188:1387.
Vitamin D and Balance in Seniors
•
•
•
124 nursing home residents (mean age 89 years)
Subjects were divided into 5 groups
For 5 months they received a daily dose of either
1.
2.
3.
4.
5.
Placebo
Vitamin D 200 IU
Vitamin D 400 IU
Vitamin D 600 IU
Vitamin D 800 IU
Vitamin D and Balance in Seniors
Continued
Results
Treatment
Placebo
Vitamin D 200 IU
Vitamin D 400 IU
Vitamin D 600 IU
Vitamin D 800 IU
# of Subjects
25
26
25
25
23
# of Falls
12
15
15
15
5
• No statistically significant differences between fall rates
below 600 IU per day
• In the 800 IU group, the fall rate was only 20%
Broe, K.E., Chen, T.C., et al. A Higher Dose of Vitamin D Reduces the Risks of Falls in Nursing Home Residents: A
Randomized, Multiple-Dose Study. Journal of American Geriatric Society. 2007;55(2):234-239.
Fasting and Balance
• 22 women (~ 22 years) were tested twice 2 weeks apart
in either a fasted (15 hours) or non-fasted state
• In a fasting state, subjects demonstrated significant
decline in functional reach (dynamic balance) and:
– Timed single limb stance (static balance) with open
eyes
– Timed single limb stance (static balance) with closed
eyes
• These findings may have application to sports such as
gymnastics
Johnson, S, Leck, K. The Effect of Dietary Fasting on Physical Balance. Med Sci Sp Ex. 2006;38(5)S117:1085
Decline in Energy Intake Causes
Decline in Energy Output
•
•
•
•
19 postmenopausal women cut 400 kcal/d for 5 months
Average weight loss was 21 lb
6 days per month subjects wore activity monitors
Spontaneous physical activity energy expenditure
dropped 10% after the first month and remained lower
for the next 4 months
Conclusion:
Reduced energy expenditure in response to energy
intake should be discussed
Wang, X., Tongjian, Y., Johnson, J., et al. Physical Activity Energy Expenditure Decreases During a 5-Month Calorie
Deficit Diet in Obese, Postmenopausal Women. Med Sci Sp Ex. 2006;38(5)S14:A636.
Obesity and Meal
Frequency Patterns
• 75 Obese subjects enrolled in a weight-loss program
• Diets ranged from 1200 to 1500 calories per day based
on subject size
• Subjects completed daily food logs that included
frequency of eating episodes
Results:
• Week 12 - 63 subjects replied and had an average
weight loss of 13.2 pounds
• Week 20 - 55 subjects replied and had an average
weight loss of 18.9 pounds
Obesity And Meal
Frequency Patterns
Continued
•
1.
2.
Conclusion:
Number of meals was not associated with the amount
of weight lost, but
Number of meals WAS associated with absolute body
weight
The smaller participants (measured by body weight)
reported eating more meals and snacks than the
individuals who weighed more
Mohr, C.R., Otto, A.D., Jakicic, J.M. Effects of Meal Periodicity on Weight Loss. Med Sci Sp Ex.
2006;38(5)S465:A2490.
Strategies of Maintaining Weight Loss
• 550 people in a university-based weight-loss program
were surveyed
• The program was based on the participants consuming
over 5 servings of fruits and vegetables a day and
performing 5 hours of exercise a week.
• For the first 3 months there were weekly meetings
followed by a maintenance program of 6-21 weeks
• 229 people responded to the survey
• 50% had maintained or continued to lose weight
• 50% had regained their lost weight
Strategies of Maintaining Weight Loss
Continued
Results:
Continued to eat 5 or more servings
of fresh fruits and vegetables a day:
Maitainers
77%
22%
•
Continued to practice portion control:
85%
14%
•
Planned ahead to eat healthy snacks
and meals:
80%
20%
•
Continued to exercise 30-60 min/day
85%
15%
•
•
Continued use of pedometer to monitor
activity level
84%
16%
•
Regainers
Stewart, E.E., Dubose, K.D., Smith, B.K., Donnelly, J.E. Weight Management Strategies of Successful Weight
Maintainers Subsequent to Clinically Relevant Weight Loss. Med Sci Sp Ex. 2006;S188:A1344
Fitness Age – An Unexpected Finding In A
Weight Loss Study
• 23 obese females underwent a 2-part program
• Part 1 – Intervention phase, 12 weeks, consisting of
water aerobics twice a week and circuit weight training
on Nautilus machines twice a week
• Part 2 – 12 weeks of weight maintenance consisting of 1
meeting per week
• The study was designed to focus on adiponectin (an
adipose-derived hormone), which increases when obese
subjects lose weight
• Other measurement factors included visceral adipose
tissue, blood lipids, and general fitness
Fitness Age – An Unexpected Finding In A
Weight Loss Study
Continued
•
•
•
•
•
Results:
Average weight loss at week 12 was 10 pounds
Triglyceride reduction was 55 mg/dL
LDL reduction was 19 mg/dL
Weight and lipid losses were maintained in the 12 week
maintenance phase
Fitness age reduced by 6.5 years in the 12 week intervention phase
and was maintained in the following 12 week maintenance phase
Comment:
• 12 weeks of moderate exercise resulted in a 6.5 year reduction in
fitness age
• This was not the reason for the study, but was the most important
finding
Fukuda, R., Nakagaichi, M., Tahara, Y. The Effect of Exercise and Weight Loss on Adiponectin on Obese Women. Med
Sci Sp Ex. 2006;38(5)S467:A2498.
Herbal Weight Loss
• A nutritional supplement claimed increased energy and
weight reduction by taking a unique formula in the
morning, afternoon, and evening that turns your body
into a “fat burning machine”
• The proprietary blend of ingredients: vitamin B12,
hypercium extract, caffeine, gugglesterones, magnesium
salicylate, bitter orange extract, guarana, theobromine,
yohimbine extract, L-tyrosine, citrin K, psyllium husk,
valerian root, ho shou wu, turkey rhubarb, cascara
sagrada, senna extract, and piper nigrum.
• 10 subjects took the product or a placebo morning, noon,
and night in a randomized, double-blind, crossover
manner
Herbal Weight Loss
Continued
• Pre- and post measurements of resting metabolic rate, respiratory
exchange ratio, heart rate (beats per minute), wingate, (A test for
anaerobic exercise performance) and body mass were all
unchanged when the placebo treatment was compared to morning,
afternoon, or evening supplementation.
Results:
• The product did not live up to its advertised claims.
• This result could be due to:
1) inadequate amounts of stimulatory substances*
2) possible ingredient antagonism
*Note: As a proprietary formula, specific amounts of the ingredients were
not disclosed
Comment: Spend your $199 elsewhere
Stahlnecker IV, A.C., Brown, G.A. Acute Effects of a Weight-Loss Supplement on Resting Metabolic Rate and
Anaerobic Exercise Performance. Med Sci Sp Ex. 2006;38(5)S403:A2242.
Ultrasound and DOM’s
• 36 subjects, divided into 4 groups:
1 control, 2 eccentric exercise, 3 eccentric exercise with
ultrasound, 4 eccentric exercise with sham
• Treated for 4 days
Results:
Ultrasound group had less swelling and stiffness
No difference between placebo group (sham US) and
untreated groups (sham US)
Plaza, P.L., Penailillo, L., Gurovich, A.N. Effects of Sham Therapeutic Ultrasound in a Controlled Trial. Med Sci Sp Ex.
2006;38(5)S25:A685.
Ultrasound and Fractures
• Preliminary evidence has emerged that specialized ultrasound
machines may accelerate fracture healing
• Researchers tested how typical ultrasound machines would affect
fractures
• Laboratory rats sustained a limb fracture and received ultrasound
therapy
• At 25 days no changes noted
• At 40 days showed 16.9% increase in bone mineral content
• BMC did not come from more minerals but from 25.8% increase in
bone area
Warden, S.J., Stewart, R.L., Fuchs, R.K., et al. Ultrasound Produced by a Conventional Therapeutic Ultrasound Unit
Accelerates Fracture Repair. Med Sci Sp Ex. 2006;38(5)S26:A686.
Biomechanics of Runners with
Achilles Tendinopathy
• 25 runners with Achilles tendinopathy were compared to 34
healthy runners
• 10 trials were done and data was collected from strain gauge
force plate, 6 infrared cameras, and a telemetric EMG system
Results:
Runners with AT have decreased knee flexion (26.2 vs 21.9
degrees). AT runners EMG data showed decreased lateral
gastroc, gluteus medius, and rectus femoris activity after heel
strike, and decreased tibialis anterior activity before heel strike.
RE: Tibialis anterior findings – researchers stated it was
“...either a novel etiological factor, or an adaptive response to
injury.”
Azevedo, L.B., Lambert, M., Vaughan, C.L., Schwellnus, M.P. Lower Limb Biomechanics and EMG Activity in Runners with
Achilles Tendinopathy. Med Sci Sp Ex. 2006;28(5)S123:A1109.
Pathogenesis Of Distal
Iliotibial Band Syndrome
• Distal iliotibial band syndrome is a common cause of lateral
knee pain
• It is currently believed that repetitive friction in an anterior to
posterior fashion over the lateral femoral condyle is the cause
of this condition
• The study was to confirm anterior to posterior movement of
the ITB over the lateral femoral condyle and thus, is indeed, a
friction syndrome
Methods:
• 8 subjects underwent MRI (6 asymptomatic and 2 with ITBS)
• Histological studies were performed on 15 cadavers
Pathogenesis Of Distal
Iliobial Band Syndrome
Continued
Results:
• The ITB is anchored to the distal femur by fibrous bands.
• MRI in healthy subjects demonstrates a firm insertion by fibrous bands of
the iliotibial tract onto the distal femur
• There is a layer of highly innervated and vascularized fat between the femur
and dense fibrous tissue confirmed by dissection
• MRI of healthy subjects reveals the insertion prevents anterior to posterior
translation
• MRI of symptomatic people displayed signal changes in the fat layer deep
to the ITB
• The cause appears to be a compression of the tract against the highly
innervated layer of fat between the ITB and epicondyle rather than repetitive
A to P frictioning.
In conclusion, ITB syndrome is caused by repetitive compression rather than
repetitive friction.
Fairclough, J., Hayashi, K., Toumi, H.H., et al. The Structure of Iliotibial Band in Relation to Iliotibial Band Friction
Syndrome. Med Sci Sp Ex. 2006;38(5)S552:A2837.
Low Back Pain In Runners
• Lifetime prevalence of low back pain in the
general population is estimated to range
between 50-90%
• Lifetime incidence of total injuries in long
distance runners is estimated to range between
37-50%
• Lifetime incidence of spinal injuries in runners is
estimated to range from 5-17%
• 99 runners (45 M, 54 F) ages 17-72 were
recruited from community running events and
surveyed
Low Back Pain In Runners
Continued
Runners with lower back pain
• Lifetime incidence of LBP
• Running aggravated LBP
• Running relieved LBP
• LBP unchanged with run
• Did not answer follow-up
58%
30%
26%
30%
14%
Low Back Pain In Runners
Continued
• Gender, age, speed, mileage & orthotics were all
categorized
• None were significant predictors of an improving or
exacerbating LBP during running
• When miles per week exceeded 20, the risk of persistent
LBP was increased 5 fold
• Not using orthotics increased the risk of persistent LBP
by 10 fold
• Neither miles per week nor orthotics were associated
with acute bouts of LBP
Gonzalez, P., Akuthota, V., et al. Prevalence of Low Back Pain in Recreational Distance Runners. Med Sci Sp Ex.
2006;38(5)S349:A2026.
Shoe Review - Purchase
• There are 3 basic types of running shoe – stability,
motion control, and cushioning
• It is best to buy a running shoe at a specialty store with
trained employees
• Must buy at a specialty store if person does not know
what type of shoe is required
• Always purchase shoes in the evening (feet will swell
during the day)
• Running shoes should be used for running only until a
replacement is purchased
Shoe Review - Breakdown
• Taking shoes off while still tied accelerates breakdown of
heel counter
• Running in wet shoes reduces shock absorption by 50%
and accelerates mid sole breakdown
• Drying damp or wet shoes with high heat accelerates
material aging; avoid the clothes dryer, hair dryer, or
space heaters and allow shoes to dry naturally
• The older the shoe, the greater the risk of injury
Shoe Review – Shock Absorption
• The mid sole is the key shock-absorbing structure of a
running shoe
• The upper and the sole may still pass visual inspection
when the mid sole has sustained significant breakdown
• Most protection is lost by 500 miles
• There is a 40% decline of cushioning by 250 miles
• Mid sole breakdown also occurs with age; a shoe that
has sat on a shelf for 2 years will have reduction in
shock absorption capability
• For higher mileage/endurance runners, alternating 2
pairs (every other run) will last as long as 3 pairs worn
continuously
Asplund, C.A., Brown, D.L. The Running Shoe Prescription. Physician and Sports Medicine. 2005;33:17-24.
Household Activity Reduces
Breast Cancer Risk
• 218,169 women age 20-80 were prospectively
studied
• Over a 6-1/3 year followup 3423 cases of breast
cancer occurred
• Regression analysis adjusted for factors
including age, alcohol use, tobacco use, body
mass index, age at menarche, age at first
pregnancy, number of pregnancies, history of
oral contraceptive use, history of hormonereplacement therapy use, and education
Household Activity Reduces
Breast Cancer Risk
Continued
Results
• Postmenopausal women in the highest quarter of
household activity had a 19% reduced risk of breast
cancer compared to postmenopausal women in the
lower quarter of household activity.
• Premenopausal women in the highest quarter of
household activity had a 29% reduced risk of breast
cancer compared to premenopausal women in the
lowest quarter of household activity.
Conclusion
Increasing total activity (specifically household activity)
was associated with a reduced risk of breast cancer in
both pre- and postmenopausal women.
Lahmann, P.H., Friedenreich, C., et al. Physical Activity and Breast Cancer Risk: The European
ProspectiveInvestigation into Cancer and Nutrition. Cancer Epidemiol. Biomarkers Prev. 2006. Pre Print Epub.
PROACTIVE STEPS YOU CAN TAKE TO
REDUCE THE RISK OF BREAST CANCER
IN THE WOMAN YOU LOVE
It is safe to take items out of:
Cabinets
Closets
Drawers
Hampers
• Just do not put anything in these structures
• Let her do it if you care about her future!
PROACTIVE STEPS YOU CAN TAKE TO REDUCE THE
RISK OF BREAST CANCER IN THE WOMAN YOU LOVE
Continued
• It is unsafe to take anything out of:
Dishwashers
Dryers
Bags of groceries
• Nor should any decent man ever take out the trash
• You want to lower her risk, not raise it!
Proactive Steps…
Continued
• Household “ings” to avoid if you love her:
Mopping
Wiping
Polishing
Sweeping
Scrubbing
Vacuuming
Painting
• Should be avoided by all males who truly care
about their wives and girlfriends
PROACTIVE STEPS YOU CAN TAKE TO REDUCE THE
RISK OF BREAST CANCER IN THE WOMAN YOU LOVE
Continued
• What about just outside the house?
• Does yardwork count as housework?
• Yes, it does!
Proactive Steps…
Continued
• “Ings” not to do just outside your home:
Raking
Pruning
Trimming
Sweeping
Mowing
Edging
Weeding
Watering
Digging
• And, of course, hoeing are activities best left to the
women we love
• “Increasing total activity (specifically household activity)
was associated with a reduced risk of breast cancer in
both pre- and postmenopausal women.”