Background: Parkinson's disease is the second most common neurodegenerative disease. Symptoms are treated by medication, physio-, exercise, and occupational therapy. Alternative methods have been used in exercise therapy for a few years now. The effect of whole-body vibration as an alternative training method has been investigated for several symptoms in Parkinson's disease. Since freezing and flexibility have not yet been investigated, the aim of this study was to evaluate the efficacy of different frequencies of application for these two symptoms.
Methods: Patients were randomly assigned to a frequency (6, 12, or 18 Hz) or the control group. Before and after the treatment of 5 × 60 s with a rest of 60 s each, the Sit and Reach test (flexibility) and the 360° turn test (freezing) were performed.
Results: Only the Sit and Reach test showed a significant improvement at 18 Hz (improvement from - 5.75 to - 1.89 cm, F(3,30) = 5.98**). At 360° turn, no significant differences were found. Weak to high effect sizes (standardized mean differences) were determined for the different frequencies, both for the Sit and Reach (from .01 to .64) and for the 360° turn (from - .72 to - 1.25). The highest effect size is observed for 18 Hz and the lowest for 6 Hz.
Conclusions: Higher frequencies seem to be more effective than lower ones. Freezing, age, and gender also seem to play a role. Therefore, this should be investigated in further studies.
Keywords: Flexibility; Freezing; Parkinson’s disease (PD); Whole-body vibration (WBV).