The effects of standard and modified LSVT BIG therapy protocols on balance and gait in Parkinson's disease: A randomized controlled trial

Background: Lee Silverman voice treatment (LSVT) BIG is an exercise program developed for patients with Parkinson's disease (PwPD), consisting of sets of exercises performed for 4 consecutive days a week for 4 weeks. However, the standard protocol suggests a treatment frequency difficult to follow for most patients who have difficulties reaching rehabilitation clinics. Our aim was to compare the standard LSVT BIG protocol with a modified LSVT (m-LSVT) BIG protocol (twice a week in the clinic for 4 weeks and twice a week at home for 4 weeks). Methods: In this randomized controlled trial, 16 PwPD (aged 18-80 years, Hoehn and Yahr stages I-III) were recruited into two groups. The LSVT group received standard LSVT BIG training (four times per week for 4 weeks at the clinic). The other group was given m-LSVT BIG exercises, but unlike the LSVT group, the m-LSVT group exercised twice a week at the clinic and twice a week at home for 4 weeks. The Berg Balance Scale was used to assess functional balance. Biodex Balance System was used to assess laboratory balance measures. Timed Up and Go test and G-Walk sensor system were used to assess functional mobility and spatiotemporal gait analysis. Results: Significant group-by-time interactions on the eyes open-firm surface score of the modified clinical test of sensory integration of balance (F = 10.138, p = .007) and gait cycle symmetry index (F = 10.470, p = .010) were found to be in favor of the LSVT group. Additionally, post hoc analyses revealed that both groups significantly improved postural stability, gait speed, motor symptoms, and functional mobility (p < .05). Conclusion: The results revealed the beneficial effects of the modified protocol on balance and gait in PwPD, as well as the superiority of the standard LSVT BIG protocol. The m-LSVT BIG protocol may be an effective intervention method, especially for PwPD who have difficulty adapting to the treatment frequency of the standard protocol.