Strength Increase after Whole
Body Vibration Compared with
Resistance training.
Christophe Delecluse, Sabine Verschueren, Machteld Roelants
Faculteit Lichamelijke Opvoeding en Kinesitherapie
Katholieke Universiteit Leuven
België
WBV-training: positive
influence on muscle strength?


Lack of scientific support
Mechanism:
vibration stimulus
stimulation sensory receptors in muscle (presumably muscle
spindles)
activation alpha motor neurons
Tonic vibration reflex leading to muscle contraction:
stimulus for increase in strength?
Studies acute effects WBV
Bosco et al. 1999 (Clin Physiol): volleyball players, increase in strength-speed,
strength-power leg press
Bosco et al. 2000 (Eur J Appl Physiol): team sports, 7% increase mechanical
power knee-extensors (leg press), 3,8% increase jump height
Torvinen et al. 2002 (Clin Physiol & Func Im): 3,2% increase isometric
strength knee-extensors, 2,5% increase jump height
Torvinen et al. 2002 (Int J Sports Med): no effects on isometric strength kneeextensors, jump height
Long term WBV studies
Bosco et al. 1998 (Biol of Sport): physically active subjects, 10 days WBVtraining, 6,1% increase in power, 12% increase jump height
Runge et al. 2000 (J Musculoskel Neuron Interact): elderly subjects, 2 months
WBV-training, 18% increase in ‘chair rising time’
Torvinen et al. 2002 (Med Sci Sports and Exc): untrained subjects, 4 months
WBV-training, 8,5% increase jump height, 2,5% increase isometric strength
knee-extensors
De Ruiter et al. 2002 (Geneeskunde en Sport): physically active subjects,no
improvement in isometric and explosive strength knee-extensors
No unambiguous results:
– Differences in training schedules, group composition,
physical condition
– No placebo group
– No comparison to regular resistance training
Purpose of this study

long term study:
– Investigate effects on isometric strength
knee-extensors of exercises performed on
platforms with and without vibration
(placebo)
– Compare effects to resistance training of
moderate intensity (10-20RM)
Method
67 young ladies (21,4±1,8 jaar)
 untrained
 4 groups (random)
WBV group, N=18
Placebo group (PL), N=19
Resistance group (RES), N=18
Control group (CO), N=12
 12 weeks, 3 x/week (36 sessions)

WBV group
PL group
Static and dynamic exercises for knee-extensors:
squat, deep squat, one legged squat, lunge,...

Vibration platform
(Power Plate®)

progressive increase in
intensity and volume
– 35-40Hz / 2,5-5,0mm
– 2,28 - 5,05g
– Total vibration time
per session: 3-20 min
– rest period: 60-5 sec

Placebo platform
- equal platform not
resulting in increased
muscle contraction
- amplitude negligible
- acceleration only 0,4g
EMG activity in the m. rectus femoris
(high squat)
EMG activity (V)
m. re ctus femoris
0.4
Control
rms=0.0528
rms=0.0461
0.3
0.2
0.1
0.0
EMG activity (V)
0
5
15
20
15
20
15
20
Plac ebo
0.4
rms=0.0603
0.3
rms=0.0641
0.2
0.1
0.0
0
EMG activity (V)
10
5
0.4
WBV 35Hz
0.3
rms=0.0591
10
rms=0.0798
0.2
0.1
0.0
0
5
10
Time (s)
VIBRATION 35 Hz
EMG activity in the m. gastrocnemius
EMG activity (V)
m. ga stroc nemius
Control
0.12
0.08
0.04
0.00
EMG activity (V)
0
5
10
15
20
15
20
15
20
Placebo
0.12
rms=0.00570
rms=0.00571
0.08
0.04
0.00
0
EMG activity (V)
rms=0.00562
rms=0.00447
5
10
WBV 35 Hz
rms=0.02151
rms=0.00400
0.12
0.08
0.04
0.00
0
5
10
Time (s)
Vibration 35Hz
Resistance-training group




University fitness centre
20 min warm up: bicycle, step, treadmill
Resistance training schedule with moderate intensity
for knee-extensors (Kraemer 2002, ACSM)
leg press, leg extension (Technogym®): 2 sets
20 RM
W1
15 RM
W3
W6
12 RM
10RM
W9
W12
Pre-post measuring

Iso-kinetic dynamometer
(REV9000, Technogym®)

maximum voluntary isometric
strength knee-extensors (angle
in knee: 130°)

post-test: min. 72 hours after
last training session
Results (1)
Knee-extensor moment (N.m)
ISO †
230
*
pre
post
*
210
190
170
150
130
110
KR
N=18
WBV
N=18
Group
PL
N=19
CO
N=12
Results (2)

Isometric strength
– significant interaction effect (group x time)

F (3)=15,94; P<0.001 (ANOVA for repeated
measurements)
– significant increase (P<0.001) pre-post (contrast analysis):
 in WBV group: 16,6 ± 10,8%
 in RES group: 14,4% ± 5,3%
– no significant difference (P>0.05) pre-post:
 in PL group: 3,8 ± 11,4 %
 in CO group: -7,3 ± 15,9%
Causes of strength gain

Hypothesis: strength gain after 12 weeks
WBV mainly due to neural adaptations ~
resistance training (Enoka 1997, J Biomech)
– extensive sensory stimulation: possible more
efficient use of sensory information in production
of strength
 input of proprioceptors (Ia, IIa, Ib) is used in
building up isometric strength (Gandevia 2001,
Physiol Rev)
Conclusions (1)


The muscle contractions during WBV efficient stimulus
for strength gain in knee extensors in untrained subjects
Torvinen et al. 2002:
– only 3,7% increase in strength in knee-extensors
after 2 months WBV-training  placebo effect this
study
Difference in training schedule:
time, volume, intensity,…
– this study: 16,6%
‘full motor unit activation’ leads
to fatigue in motor units =
stimulus to strength gain
(Sales 1987, Exerc Sport Sci Rev)
Conclusions (2)

12 weeks WBV training with untrained
ladies:
– Strength gain in knee-extensors comparable to
resistance training of moderate intensity (10-20RM)
– effect not attributable to stance or exercises on
platform but to increased muscle activity (EMG) during
WBV
 NO placebo-effect

Strength gain following 12 weeks of
whole body vibration training
– C. Delecluse, M. Roelants, S. Verschueren

Published in Medicine and Science in Sports and
Exercise Vol.35, No.6, pp. 1033-1041, 2003