## 4 Results and Discussion
### WBVE and Quality of Life  
The negative impact of the COVID-19 on health-related QoL e has been demonstrated in various populations [78]. WBV training exercise can improve the QoL of individuals in different clinical conditions, as reported by [PERSON] et al., 2020 [49] and [PERSON] et al., 2017 [79] in patients suffering from MSy, [PERSON] et al., 2018 [80] in Chronic Obstructive Pulmonary Disease (COPD), [PERSON] et al., 2016 [34] in knee osteoarthritis (KOA), [PERSON] et al., 2020 [81] in non-alcoholic fatty liver disease patients, [PERSON] al., 2019 [82] in painful diabetic peripheral neuropathy, [PERSON] et al., 2020 [83] in renal transplantation, and [PERSON] et al., 2016 [84] in elderly adults. The samples consisted of individuals of both sexes tested on vertical and alternating platforms. The frequency used ranged from 5 to 40 Hz and the peak-to-peak displacement from 0.8 mm to 7.5 mm. The duration of the WBV training exercise consisted of 6 to 24 weeks. In all studies, positive effects of WBV on the QoL were observed. [PERSON] et al., 2020 [49] investigated a protocol performed weekly (one and two sessions a week) for 10 weeks. The session was performed with 1 min or vibration followed 1 min of rest. This sequence was repeated more two times. The CG followed the same protocol-treated group, however, kept the platform off. They found that WBVE in MSy individuals is capable significantly (i) to promote an improvement of QoL considering the physical and psychological domains, as accumulative effect; and (ii) to reduce CP level in the acute interventions in the first and in the last sessions. Therefore, WBVE would represent a suitable and useful physical activity that could be included in health programs for MSy individuals, following the World Health Organization recommendations, and [PERSON] et al., 2017 [79], found the WBVE improving the QoL of patients with MSy in different domains of the WHOQOL-BREF, in a same protocol (one or two times per week) with a progressive and increased frequency. [PERSON] et al., 2018 [80] concluded that the WBVT was related to beneficial effects on physical measures and QoL in patients with stable moderate COPD and did not change the inflammatory-oxidative biomarkers. The protocol was 3 times/week on alternate days, for 12 week, performing six series of 30 s with 60 s of rest between each series. The control group performed equal procedures, with the vibrating machine off. Moreover, the WBVT showed to be an integrated method, capable of improving cardiorespiratory and muscle components related to exercise capacity, QoL, and peripheral muscle strength in moderate COPD patients. [PERSON] [PERSON] et al., 2016 [34] WBVE in combination with quadriceps resistance exercises (QRE) provided over 24-week period improved symptoms, physical function, ADL, and QoL in patients with KOA to a great extent and was superior to QRE only in most outcomes. This was observed after a total exposure time of 30 min per day (vibration 60 s, interval rest 60 s), 5 days/week for 24 weeks. [PERSON] et al., 2020 [81] concluded, after an eight-week individualized exercise program with 15 min WBV, that aerobic training with and without the WBV was effective in physical adaptation and improving the QoL in many well-being domains; however, it was understood that there was no need to add the WBV for better recovery of QoL. [PERSON] et al., 2019 [52] used a protocol with four bouts of three min sessions with 60 s rest between bouts, three times a week. The protocol was performed over six weeks and it was pointed that WBV proved to be beneficial in terms of neuropathic pain, neuropathy disability score, balance measures and QoL in patients with painful diabetic peripheral neuropathy. It was verified that individuals with advanced stages of neuropathy that present difficult-to-perform exercise programs, WBV could be considered as safe and feasible intervention to improve functionality, considering all domains of SF-36 questionnaire.