Effects of Whole-Body Vibration Training on Lower Limb Muscle Strength and Physical Performance Among Older Adults: A Systematic Review and Meta-analysis

Objective To evaluate the effects of whole-body vibration training (WBVT) on lower limb muscle strength and physical performance in older adults. Data Sources Web of Science, PubMed, Cochrane Library, and MEDLINE databases were searched for papers published in English, from January 1, 2000, to May 30, 2022. Study Selection Randomized controlled trials of WBVT in older adults (mean age, 65 years or older) published in English. The Physiotherapy Evidence Database Scale was used to assess the quality of the selected studies. Data Extraction Two investigators independently assessed articles according to the evaluation criteria. Differences between investigator assessments were resolved by consulting a third investigator before reassessment. Data Synthesis Systematic review of 18 randomized controlled studies found that WBVT produced significant improvements in lower limb muscle strength and physical performance among older adults. We used the Cochrane Collaboration method to assess risk of bias and RevMan version 5.4a to extract means and calculate SDs. WBVT significantly improved knee strength (standard mean difference [SMD]=0.72, 95% confidence interval [CI] [0.38, 1.07], P<.0001, I2=58%) and explosive power (SMD=0.47, 95% CI [0.10, 0.83], P=.01, I2=0%) among older adults. Significant improvements in each physical performance were observed in the sit-to-stand test (SMD=0.57, 95% CI [0.30, 0.84], P<.0001, I2=35%), the subgroup of studies that evaluated balance with timed Up and Go test, SMD was 0.53 (95% CI [0.19, 0.88], P=.002, I2=56%) and the Tinetti total score, SMD was 0.72 (95% CI [0.04, 1.41], P=.04, I2=81%), walking speed (SMD=0.46, 95% CI [0.14, 0.77], P=.005, I2=49%), and walking endurance (SMD=0.43, 95% CI [0.02, 0.85], P=.04, I2=24%). Conclusions WBVT may be an effective intervention to improve lower limb muscle strength and physical performance in older adults. Tinetti total score remains controversial and warrants assessment in future high-quality randomized controlled trials.