Treadmill training frequency influences walking improvement in subjects with Parkinson's disease: a randomized pilot study

Background. Treadmill Training (TT) has been indicated as a potential therapeutic tool for improving balance and gait in patients with Parkinson’s disease (PD). However, the lack of evidences about the best modality of intervention (e.g.: number of sessions) and the lack of reliable follow-up measures, made difficult to hand down these results into the clinical practice. Aim. To compare the efficacy of 3 different modalities of TT program on gait performance in PD patients. Design. A randomized, single-blind pilot study Setting. Outpatients clinic, Department of Neuroscience, University of Genoa Population. 30 patients (out of 42 screened) with PD were randomized. Methods. Participants underwent the same TT program (ten sessions, 45 minute each) but with a different frequency throughout a week: i) low-frequency (LF) group: 2-times a week, ii) intermediate-frequency (IF) group: 3-times a week and iii) high-frequency (HF) group: 5-times a week. Patients were evaluated by Timed Up and Go (TUG) test, 10-meter walking test (10M-WT), Berg Balance Scale (BBS), Falls efficacy scale (FES) and falls diary before TT, immediately after the training was stopped, and 2 and 4 months later. Results. At baseline, no significant differences were found among groups. Immediately after the end of the TT, TUG test, 10 MWT, FES and falls diary scores significantly improved only in the LF and IF groups, whereas they did not no change in the HF group. Improvements were sustained for up 2-months in the IF and LF groups. At 4-months evaluation, outcome measures were either comparable or sometimes even better than at baseline in the LF and IF groups, whereas in the HF group, 10M-WT and FES score worsened. Conclusions. According to the results of this study, we might postulate that the frequency of TT influences short and long-lasting effects on walking performance and falls. Clinical rehabilitation impact. The present study confirms that TT is effective in improving gait disturbances and reducing falls risk in patients with PD. The short- and long-lasting effects induced by TT on walking performance are specifically affected by the frequency of training, possibly in relationship to learning mechanisms and fatigue.