Article

The aim of this study was to identify the frequency of whole-body
vibration (WBV) that elicits the greatest improvement in lower limb power output
after an acute exposure in older women, with the hypothesis that an
individualized optimal vibration frequency (OVF) would be more effective than a
fixed vibration frequency. DESIGN: Maximal power output was measured during a
double leg press on an isoinertial dynamometer in nine women with a mean (SD) age
of 71 (3) yrs, 1 and 5 mins after WBV on a platform at three different
frequencies, in a random order: 20 Hz, 50 Hz, and OVF, determined for each
subject by identifying the frequency corresponding to the maximal
electromyographic muscle response. RESULTS: The mean (SD) OVF was 33 (2.5) Hz.
The 25.9% increase in maximal power output after 1 min of WBV at OVF was
significantly higher (P < 0.05) than the 14.3% increase after 1 min of WBV at 20
Hz. Similarly, the 32.1% increase in maximal power output after 5 mins of WBV at
OVF was significantly higher (P < 0.01) than the 16.1% and 16.3% increase after 5
mins of WBV at 20 Hz and 50 Hz, respectively. CONCLUSIONS: Frequency of WBV
should be prescribed in an individualized fashion, within the range of 30-35 Hz
in this target population of older women.

Langue : ANGLAIS