Parkinson disease (PD) is a progressive, neurodegenerative movement disorder with symptoms reflecting various impairments and functional limitations, such as postural instability, gait disturbance, immobility and falls. In addition to pharmacological and surgical management of PD, exercise and physical therapy interventions are also being actively researched. This Review provides an overview of the effects of PD on physical activity - including muscle weakness, reduced aerobic capacity, gait impairment, balance disorders and falls. Previously published reviews have discussed only the short-term benefits of exercises and physical therapy for people with PD. However, owing to the progressive nature of PD, the present Review focuses on the long-term effects of such interventions. We also discuss exercise-induced neuroplasticity, present data on the possible risks and adverse effects of exercise training, make recommendations for clinical practice, and describe new treatment approaches. Evidence suggests that a minimum of 4 weeks of gait training or 8 weeks of balance training can have positive effects that persist for 3-12 months after treatment completion. Sustained strength training, aerobic training, tai chi or dance therapy lasting at least 12 weeks can produce long-term beneficial effects. Further studies are needed to verify disease-modifying effects of these interventions.

Postural instability and falls are complex and disabling features of Parkinson's disease (PD) and respond poorly to anti-Parkinsonian medication. There is an imperative need to evaluate the effectiveness of exercise interventions in enhancing postural stability and decreasing falls in the PD population. The objectives of our study were to determine the effects of exercise training on the enhancement of balance and gait ability and reduction in falls for people with PD and to investigate potential factors contributing to the training effects on balance and gait ability of people with PD. We included 25 randomized control trials of a moderate methodological quality in our meta-analysis. The trials examined the effects of exercise training on balance and gait ability and falls against no intervention and placebo intervention. The results showed positive effects of exercise intervention on enhancing balance and gait performance (Hedges' g = 0.303 over the short-term in 24 studies and 0.419 over the long-term in 12 studies; P < .05) and reducing the fall rate (rate ratio = 0.485 over the short-term in 4 studies and 0.413 over the long-term in 5 studies; P < .05). The longest follow-up duration was 12 months. There was no evidence that training decreased the number of fallers over the short- or long-term (P > .05). The results of our metaregression and subgroup analysis showed that facility-based training produced greater training effects on improving PD participants' balance and gait ability (P < .05). The findings support the application of exercise training to improve balance and gait ability and prevent falls in people with PD.

Background Fear of falling has been identified as an important and independent fall-risk predictor in patients with Parkinson's disease (PD). However, there are inconsistent findings on the effects of balance and gait training on balance confidence. Objective To explore whether balance and gait training with augmented feedback can enhance balance confidence in PD patients immediately after treatment and at 3- and 12-month follow-ups. Methods A total of 51 PD patients were randomly assigned to a balance and gait training (BAL) group or to an active control (CON) group. The BAL group received balance and gait training with augmented feedback, whereas CON participants received lower-limb strength training for 12 weeks. Outcome measures included Activities-Specific Balance Confidence (ABC) Scale, limits-of-stability test, single-leg-stance test, and spatiotemporal gait characteristics. All tests were administered before intervention (Pre), immediately after training (Post), and at 3 months (Post3m) and 12 months (Post12m) after treatment completion. Results The ABC score improved marginally at Post and significantly at Post3m and Post12m only in the BAL group (P < .017). Both participant groups increased their end point excursion at Post, but only the BAL group maintained the improvement at Post3m. The BAL group maintained significantly longer time-to-loss-of-balance during the single-leg stance test than the CON group at Post3m and Post12m (P < .05). For gait characteristics, both participant groups increased gait velocity, but only the BAL group increased stride length at Post, Post3m, and Post12m (P < .017). Conclusions Positive findings from this study provide evidence that BAL with augmented feedback could enhance balance confidence and balance and gait performance in patients with PD.

The present study aimed to examine whether fear of falling (FoF) could independently predict recurrent falls in people with Parkinson's disease (PD). Seventy patients with PD completed the study. Thirty-two patients had fallen at least once in the previous 12 months. Most of patients with PD had moderate disease severity (Hoehn and Yahr stage III). FoF was assessed by the activities-specific balance confidence (ABC) scale. PD specific motor and balance impairment was determined by Unified PD rating scale (UPDRS). Functional mobility was measured by timed-up-and-go (TUG) test. All patients were followed for 12 months by phone interview to register monthly fall incidence. Results of stepwise discriminant analysis showed that after adjusting for the fall history (F = 32.57, P < 0.001) and UPDRS motor score (F = 25.23, P < 0.001), ABC score (F = 18.84, P < 0.001) remained as a significant predictor of recurrent falls. We further established that a cut-off ABC score of 69 (i.e. 0-100, 0 indicates no confidence and 100 indicates full confidence) demonstrated the best sensitivity (93%) in predicting future falls in PD patients. The results indicate that those with an ABC score <69 at baseline had significantly higher risk of sustaining recurrent falls in the next 12 months. Findings of the present study highlight the importance of considering FoF during fall risk assessment in patients with PD.

The study aimed to compare the fall characteristics between parkinsonian single (P-SF) and recurrent fallers (P-RF), and the clinical features among parkinsonian non-fallers (P-NF), P-SF, P-RF and age-matched healthy controls. As many as 72 patients with PD and 74 healthy subjects completed the study. Each subject was evaluated for gait speed, timed up-and-go test, one-leg-stance test, six-minute walk test, five-times-sit-to-stand test, and Activities-specific Balance Confidence (ABC) scale at baseline. Subjects were then followed up for 12 months by telephone interview to record the fall incidence and fall characteristics. Among the PD patients, 12 fell once (P-SF) and 13 fell 2-29 times (P-RF), accounting for a total of 133 falls in the 12-month follow-up period. The most common fall-related activity for both P-SF and P-RF was walking. P-SF fell mostly outdoors due to "tripping", while P-RF mostly fell at home due to "muscle giving way". Clinical measures indicated that P-SF did not differ from P-NF. However, P-RF had significantly longer five-times-sit-to-stand time, shorter 6-min walk distance, and lower ABC score than P-SF. P-RF could be distinguished from P-SF by fall characteristics (i.e. location and perceived causes of falls), and by clinical measures including leg muscle weakness, reduced exercise endurance and increased level of fear of falling. Findings from the present study suggest that P-NF/P-SF and P-RF may require different intervention strategies to prevent future falls.