Immediate effect of whole-body vibration on the motor function of patients with stroke: a randomized clinical trial

Stroke is a relevant public health problem, due to its high frequency and strong impact on the population. It is classified as one of the four most common causes of death worldwide and is considered to be a disabling disease, which limits the patients' quality of life. The aim of this paper was to investigate the immediate effects of whole body vibration on the motor function of patients affected by stroke. This is a randomized clinical trial, where forty-three hemiparetic subjects, due to stroke sequel, were allocated (33 for the intervention group - IG - and 10 for the control group - CG). For the IG subjects a vibratory therapy (50 Hz frequency and 2 mm amplitude) session was applied consisting of four series of stimulation of 1-minute each with a 1-minute resting interval among all series, in three different positions: bipodal landing position with knees bent at 30º then at 90º and finally, unipodal landing position on the hemiparetic limb. The tests used for the analysis were the 6 minute walking test (6MWT), stair climbing test (SCT), time get-up-and-go test (TGUGT) and electromyographic evaluation (EMG). The latter was applied simultaneously, at isometric voluntary contraction, of tibialis anterior and rectus femorais muscles', both affected and unaffected sides (TAA and TAU ; RFA and RFU) respectively. For statistical analysis, the independent t test was applied to compare the baseline characteristics of the groups and the paired t test as well as ANCOVA to determine the effect of the intervention in both the groups and time. The results show no evidence of effects in group and time interaction for the RFA, RFU, TAA, TAU and SCT variables (p?0.05). There is evidence of effect on the group interaction for the 6MWT and TGUGT variables (p<0.05). It was concluded that, the immediate effects of whole body vibration have not contributed for the improvement of stroke-patients' functional motor.