Article

The aim of this study was to compare the optimal vibration frequency
(OVF), which corresponds to maximal electromyographic muscle response during
whole-body vibration, between young, middle-aged, and older women in four muscles
of the lower-limbs. DESIGN: OVF was measured as the frequency corresponding to
maximal root mean square of the surface electromyogram (RMSmax) during a
continuous incremental protocol, with a succession of vibration frequencies from
20 to 55 Hz (A = 2 mm), on the vastus lateralis, vastus medialis, rectus femoris,
and gastrocnemius lateralis muscles of the dominant lower-limb. Seventy-eight
women were divided into three age groups, that is, young, 21.6 +/- 2.4 yrs;
middle aged, 43.0 +/- 5.2 yrs; and older, 74.2 +/- 6.0 yrs. RESULTS: OVF in the
vastus medialis was lower in the older women than in the middle-aged and young
women, whereas OVF in the vastus lateralis was lower in the older than in the
young women. There were no differences in OVF between muscles within each group.
RMSmax was higher in the older than in the young women in all muscles.
CONCLUSIONS: Age range should be taken into consideration when determining OVF
because it decreases with age. Properly individualizing the vibration protocol
might greatly influence neuromuscular effects of vibration training.

Langue : ANGLAIS