The effects of whole body vibration training on physical activity, muscle strength and pulmonary functions in individuals with COVİD-19

Our study aimed to evaluate the effects of whole-body vibration training (WBVT) on respiratory functions, muscle strength, functional capacity, physical activity, and quality of life in individuals recovering from COVID-19, using a randomized controlled double-blind design. Forty-two participants aged 18 and over who met the inclusion criteria were enrolled. The WBVT group (n=21) received WBVT and respiratory exercises three times a week for eight weeks, while the control group (n=21) received only respiratory exercises. At baseline and post-intervention, all participants' respiratory functions were assessed using spirometry, dyspnea level was measured using the Modified Medical Research Council Dyspnea Scale (mMRC), functional capacity was evaluated with the 6-minute walk test (6MWT), 6-minute pegboard and ring test (6PRT), and COVID-19 Post-functional Status Scale (PCFS), peripheral muscle strength was measured using a portable hand dynamometer, physical activity was monitored with the Actigraph GT3X device and International Physical Activity Questionnaire (IPAQ), and quality of life was assessed using the EuroQol-5D-3L questionnaire, anxiety and depression levels were evaluated using the Hospital Anxiety and Depression Scale (HADS) and Impact of Events Scale (IES-G), fatigue level was measured using the Chalder Fatigue Scale (CFQ-11) and Visual Analog Scale (VAS), frailty was assessed using the Clinical Frailty Scale (CFS), activities of daily living were assessed using the Lawton-Brody Instrumental Activities of Daily Living Scale and Barthel Index, balance was measured using the TETRAX® static posturography device and sit-to-stand test (STS), sleep quality was evaluated with the Pittsburgh Sleep Quality Index (PSQI), pain was assessed using the Nordic Musculoskeletal Questionnaire, symptoms were evaluated using the COVID-19 Yorkshire Rehabilitation Scale (C19-YRS), and physical performance was assessed using the Short Physical Performance Battery (SPPB). Following the intervention, significant improvements were observed in spirometry measurements in all groups (p<0.05), with a greater improvement in forced vital capacity (FVC) observed in the WBVT group. Significant improvements were also noted in mMRC, 6MWT, 6PRT, C19-YRS, and PSQI measurements in the WBVT group (p<0.05). The increase in peripheral muscle strength measurements was more significant in the WBVT group compared to the control group (p<0.001). While TETRAX measurements were not significant for both groups (p>0.05), STS and SPPB scores were significant, with greater improvements observed in the WBVT group. According to the Nordic questionnaire, significant changes were observed in all measurements except wrist and shoulder pain in the WBVT group (p<0.05). Significant changes were observed in PCFS, CFQ-11, CFS, IES-G, and EQ5D-3L scales post-treatment in both groups, with only CFQ-11 total score and EQ5D-3L VAS score showing more significant improvement compared to the control group. According to the IPAQ, both groups showed significant improvements in walking and total physical activity (p<0.05). Based on accelerometer measurements, the WBVT group showed significant changes in light physical activity, total step count, and total MET-minutes compared to the control group. However, there were no significant changes observed in the Lawton Brody scale and Barthel Index. In conclusion, our study suggests that WBVT provides additional benefits in respiratory functions, muscle strength, balance, functional capacity, quality of life, sleep, and physical activity in individuals recovering from COVID-19.