Effect of four-month vertical whole body vibration on performance and balance.
OBJECTIVE
This randomized controlled study was designed to investigate the effects of a 4-month whole body vibration-intervention on muscle performance and body balance in young, healthy, nonathletic adults.


METHODS
Fifty-six volunteers (21 men and 35 women, aged 19-38 yr) were randomized to either the vibration group or control group. The vibration-intervention consisted of a 4-month whole body vibration training (4 min.d(-1), 3-5 times a week) employed by standing on a vertically vibrating platform. Five performance tests (vertical jump, isometric extension strength of the lower extremities, grip strength, shuttle run, and postural sway on a stability platform) were performed initially and at 2 and 4 months.


RESULTS
Four-month vibration intervention induced an 8.5% (95% CI, 3.7-13.5%, P=0.001) net improvement in the jump height. Lower-limb extension strength increased after the 2-month vibration-intervention resulting in a 3.7% (95% CI, 0.3-7.2%, P=0.034) net benefit for the vibration. This benefit, however, diminished by the end of the 4-month intervention. In the grip strength, shuttle run, or balance tests, the vibration-intervention showed no effect.


CONCLUSIONS
The 4-month whole body vibration-intervention enhanced jumping power in young adults, suggesting neuromuscular adaptation to the vibration stimulus. On the other hand, the vibration-intervention showed no effect on dynamic or static balance of the subjects. Future studies should focus on comparing the performance-enhancing effects of a whole body vibration to those of conventional resistance training and, as a broader objective, on investigating the possible effects of vibration on structure and strength of bones, and perhaps, incidence of falls of elderly people.
Torvinen
Saila
S
Bone Research Group, UKK Institute, Kaupinpuistonkatu 1, FIN-33500 Tampere, Finland. losato@uta.fi
Kannus
Pekka
P
Sievänen
Harri
H
Järvinen
Tero A H
TA
Pasanen
Matti
M
Kontulainen
Saija
S
Järvinen
Teppo L N
TL
Järvinen
Markku
M
Oja
Pekka
P
Vuori
Ilkka
I
D000328:Adult; D000704:Analysis of Variance; D015444:Exercise / Q000502:physiology; D005260:Female; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D008297:Male; D009043:Motor Activity / Q000502:physiology; D018482:Muscle, Skeletal / Q000502:physiology*; D004856:Postural Balance / Q000502:physiology*; D014732:Vibration