Optimal frequency/time combination of whole body vibration training for developing physical performance of people...

To determine whether frequency and exposure time to whole body vibration influenced its effects on physical performance in seniors with sarcopenia.

Randomized controlled trial Setting: A university sports training laboratory.

Eighty community dwelling seniors with sarcopenia were recruited.

Participants were randomly divided into 4 groups, namely, low-frequency (LG: 20Hz x 720s), medium-frequency (MG: 40Hz x 360s), high-frequency (HG: 60Hz x 240s) and control (CG: no extra training) for 12 weeks of whole body vibration training and 12 weeks of follow-up.

Assessments were done at baseline, mid-intervention, post-intervention, mid-follow-up, and final follow-up for five-repetition sit-to-stand, 10-meter walking test with self-preferred speed and timed-up-and-go test.

There was significant time × group interaction effect in timed-up-and-go test (F_{12, 304} = 3.333, effect size = 0.116, p < 0.001). Between-group differences in percentage change from baseline were significant between medium-frequency group and control group on all outcome variables after 12-week whole body vibration training (Five-repetition sit-to-stand test: 10.46 ± 2.28 (-16.12%), p = 0.008; 10-meter walking test: 1.05 ± 0.16 (11.18%), p = 0.04; Timed-up-and-go test: 11.32 ± 1.72 (-15.08%), p = 0.001).

With the total number of vibrations controlled, the combination of 40Hz and 360s of whole body vibration has the best outcome on physical performance of people with sarcopenia.