Acute effects of whole body vibration and weighted vest on muscle strength and balance in elderly

Abstract

This study aimed to investigate the physiological consequence of an acute bout of whole body vibration (WBV) combined with wearing a weighted vest (WBV+WV) compared to WBV or WV alone. Fifty-two elderly volunteers (65.2 ± 3.7 years, mean ± standard deviation (SD)) were randomly allocated into 3 groups: WBV (n= 17, 10 sets of 1 minutes squat exercises interspersed with 60 s rest on a vibration platform with a frequency of 30 Hz and amplitude 2 mm), WV (n= 16, the same squat exercises with an additional 10% of bodyweight loaded into a weighted vest) and WBV+WV (n= 19, combination of both regimes). Heart rate was monitored at baseline, during and 15 minutes post-exercise, while muscle strength, balance, and functional mobility were measured before and 15 minutes post-exercise. Heart rate increased significantly with acute exercise but was not different between groups throughout the experiment. Compared to pre-exercise, WBV improved muscle strength (11% ± 5.6%, mean ± 95% CI, p-Value < 0.01), single leg stance test (43.5% ± 22.1%, p-Value < 0.01), and timed up and go test (5.3% ± 2.7%, p-Value < 0.01) 15 minutes post-exercise, while the WV exercise showed improvement only in timed up and go test (3.9% ± 1.3%, p-Value < 0.01).  Compared to pre-exercise, combining WBV+WV increased single leg stance test (40.8% ± 37.7%, p-Value = 0.01) and timed up and go test (3.9% ±1.3%, p-Value < 0.01) post-exercise. Since WBV had an acute improvement on all outcomes, it may be useful as a warm-up activity for older adults.