Treadmill training for the treatment of gait disturbances in people with Parkinson's disease: a mini-review

Use of Transcranial Magnetic Stimulation to Probe Neuroplasticity and Predict Gait Performance After Treadmill Training in Parkinson's Disease

BACKGROUND

Reduced step length is a hallmark of gait disturbance in people with Parkinson's disease (PD). Although treadmill training is effective for improving step length, the associated neural mechanisms have not been fully investigated. Moreover, exploring the baseline neurophysiological predictors for step length improvement after training could facilitate personalized gait rehabilitation for PD.

OBJECTIVE

The aim of this study was to investigate the neuroplastic changes in corticomotor excitability after treadmill training and to explore whether baseline neurophysiological measures could predict step length improvement in PD.

METHODS

Data from 61 participants with idiopathic PD who completed 12 treadmill training sessions were included. Gait performances and corticomotor excitability measured by transcranial magnetic stimulation (TMS) were obtained at baseline, postintervention, and 1-month follow-up. TMS outcomes included motor-evoked potentials, cortical silent period (CSP), intracortical facilitation (ICF), and short-interval intracortical inhibition (SICI). General estimating equation analysis and principal-component analyses were used to determine the neuroplastic changes induced by training, and multiple linear regression analysis was performed to explore the baseline TMS predictors for step length improvement at 1-month follow-up.

RESULTS

After treadmill training, SICI and CSP significantly increased and shared an emerging relationship. Regression analysis showed that female sex and greater baseline ICF and SICI were significant predictors of step length improvement at the follow-up.

CONCLUSIONS

This study advanced the understanding of neuroplastic changes induced by treadmill training in PD and showed that preserved SICI and ICF were predictors for lasting step length improvement after training. Future studies could investigate other influential factors for treadmill training in PD. © 2024 International Parkinson and Movement Disorder Society.

Exercise your graft - An important lesson for cell replacement therapy for Parkinson's disease

Parkinson's disease (PD) is a complex multisystem, chronic and so far, incurable disease affecting millions of people worldwide. With the continuing need for better therapeutic options for PD, there is a global renewed interest in cell replacement therapy due to progress in using pluripotent stem cells as an unlimited source of dopaminergic (DA) neurons for cell transplantation. Despite the significant progress made, obstacles remain that interfere with the restoration of functional circuits by DA grafts. The functional connectivity between DA grafts and host cells may be enhanced by adjunctive therapies, such as physical activity. Exercise modalities, such as use of treadmill, enhance neuroplasticity and improve motor and cognitive functions in PD patients. The patients are able to re-learn movement and adjust their posture, which, in turn, results in short term-reduced rigidity and improved stride length and cadence. By stabilizing selected active inputs and eliminating inactive ones, activity-dependent mechanisms fine-tune new neural circuits for optimal connection and physiological function. This communication will review the mechanisms and synergies between cell replacement therapy and physical and cognitive training to enhance induced pluripotent stem cell-mediated functional reinnervation of the striatum in PD.

Lower-Limb Exoskeletons for Gait Training in Parkinson's Disease: The State of the Art and Future Perspectives

Gait dysfunction (GD) is a common impairment of Parkinson's disease (PD), which negatively impacts patients' quality of life. Among the most recent rehabilitation technologies, a lower-limb powered exoskeleton (LLEXO) arises as a useful instrument for gait training in several neurological conditions, including PD. However, some questions relating to methods of use, achievable results, and usefulness compared to traditional rehabilitation methodologies still require clear answers. Therefore, in this review, we aim to summarise and analyse all the studies that have applied an LLEXO to train gait in PD patients. Literature research on PubMed and Scopus retrieved five articles, comprising 46 PD participants stable on medications (age: 71.7 ± 3.7 years, 24 males, Hoehn and Yahr: 2.1 ± 0.6). Compared to traditional rehabilitation, low-profile lower-limb exoskeleton (lp-LLEXO) training brought major improvements towards walking capacity and gait speed, while there are no clear major benefits regarding the dual-task gait cost index and freezing of gait symptoms. Importantly, the results suggest that lp-LLEXO training is more beneficial for patients with an intermediate-to-severe level of disease severity (Hoehn and Yahr > 2.5). This review could provide a novel framework for implementing LLEXO in clinical practise, highlighting its benefits and limitations towards gait training.

Influence of Verbal Instruction on Gait Training in Parkinson Disease: A Randomized Controlled Trial

OBJECTIVE

Verbal instruction is one of the most commonly used methods that therapists use to correct walking pattern for people with Parkinson disease. This study aimed to compare the long-term training effects of two different verbal instructions that either asked the participants to "take big steps" or "strike the ground with the heel" on walking ability in individuals with Parkinson disease.

DESIGN

Forty-five participants with Parkinson disease were randomized into the big-step or heel strike group. The participants underwent 12 sessions of treadmill and overground gait training. Throughout the interventions, the big-step group received an instruction to "take big steps," while the heel strike group received an instruction to "strike the ground with your heel." The primary outcome was gait performance, including velocity, stride length, cadence, and heel strike angle. The participants were assessed before, immediately after, and 1 mo after training.

RESULTS

Both groups showed significant improvements in gait performance after training. The heel strike group showed continuous improvements in velocity and stride length during the follow-up period; however, the big-step group showed slightly decreased performance.

CONCLUSIONS

A verbal instruction emphasizing heel strike can facilitate long-term retention of walking performance in people with Parkinson disease.

A backward cycling programme for people with Parkinson's disease: a feasibility and preliminary results study

OBJECTIVE

To assess the feasibility of backward cycling for people with Parkinson's disease. Secondary objectives were to assess changes in gait and balance following a 6-week program.

DESIGN

A single-group prospective pre-test, post-test study with 1-month follow-up.

SUBJECTS/PATIENTS

Twenty-six people with Parkinson's disease (mean age: 69 (7.74) years, gender: 83% males, time since diagnosis: 6 (4.44) years).

METHODS

Participants pedaled backward on a stationary bicycle for 30 minutes at moderate intensity twice a week for 6 weeks. Feasibility was assessed by acceptability, suitability, and burden. Data collected at pre- and post-intervention with 1-month follow-up included backward stepping response variables, forward/backward gait variables, Mini-Balance Evaluation Systems Test (MBT), and 6 Minute Walk Test.

RESULTS

There was a high retention rate (95.8%) and adherence rate (100%) with one adverse event and minimal burden. Significant improvements were seen in step count and excursion distance during backward stepping responses, forward and backward gait velocity, forward step length, and the Mini-BESTest.

CONCLUSION

Backward cycling was a feasible intervention for people with Parkinson's disease, demonstrating low burden with high retention and adherence rates, and it is a safe exercise with the potential for benefits in gait and balance variables.

A novel nonlinear bispectrum analysis for dynamical complex oscillations

In this study, we proposed a novel set of bispectrum in constructing both frequency power and complexity spectrum. The uniform phase empirical mode decomposition (UPEMD) was implemented to obtain nonlinear extraction while guaranteeing explicit frequencies. Lepel-Ziv complexity (LZC) and frequency power per mode were used for comprehensive frequency spectra. To examine the performances of the proposed method and meanwhile optimize routine methodological parameters, either chaotic logistic maps or a default non-stationary simulation in 40 ~ 60 Hz along with several challenges were designed. The simulation results showed the UPEMD-based LZC spectrum distinguishes the degree of complexity, reflecting the bandwidth and noise level of the inputs. The UPEMD-based power spectrum on the other side presents power distribution of nonlinear and nonstationary oscillation across multiple frequencies. In addition, given gait disturbance is an unsolved symptom in adaptive deep brain stimulation (DBS) for Parkinson's disease (PD), meanwhile considering the representative of deep brain activities to the complex oscillations, such data were analyzed further. Our results showed the high-frequency band (45 ~ 80 Hz) of the UPEMD-based LZC spectrum reflects the impact of auditory cues in modulating the complexity of DBS recording. Such an increase in complexity (45 ~ 60 Hz) reduces shortly after the cue was removed. As for the UPEMD-based power spectrum, decreasing power over the higher frequency region (> 30 Hz) was shown with auditory cues. These results manifest the potential of the proposed methods in reflecting gait improvement for PD. The proposed bispectrum reflected both the nonlinear complexity and power spectrum analyses, enabling examining targeted frequencies with refined resolution.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11571-023-09953-z.

Research progress on the application of anti-gravity treadmill in the rehabilitation of Parkinson's disease patients: a mini review

Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by motor and non-motor symptoms. It is the second most common chronic progressive neurodegenerative disease. PD still lacks a known cure or prophylactic medication. Current treatments primarily address symptoms without halting the progression of PD, and the side effects of dopaminergic therapy become more apparent over time. In contrast, physical therapy, with its lower risk of side effects and potential cardiovascular benefits, may provide greater benefits to patients. The Anti-Gravity Treadmill is an emerging rehabilitation therapy device with high safety, which minimizes patients' fear and allows them to focus more on a normal, correct gait, and has a promising clinical application. Based on this premise, this study aims to summarize and analyze the relevant studies on the application of the anti-gravity treadmill in PD patients, providing a reference for PD rehabilitation practice and establishing a theoretical basis for future research in this area.

Visual feedback improves propulsive force generation during treadmill walking in people with Parkinson disease

Persons with Parkinson's disease experience gait alterations, such as reduced step length. Gait dysfunction is a significant research priority as the current treatments targeting gait impairment are limited. This study aimed to investigate the effects of visual biofeedback on propulsive force during treadmill walking in persons with Parkinson's. Sixteen ambulatory persons with Parkinson's participated in the study. They received real-time biofeedback of anterior ground reaction force during treadmill walking at a constant speed. Peak propulsive force values were measured and normalized to body weight. Spatiotemporal parameters were also assessed, including stride length and double support percent. Persons with Parkinson's significantly increased peak propulsive force during biofeedback compared to baseline (p <.0001, Cohen's dz = 1.69). Variability in peak anterior ground reaction force decreased across repeated trials (p <.0001, dz = 1.51). While spatiotemporal parameters did not show significant changes individually, stride length and double support percent improved marginally during biofeedback trials. Persons with Parkinson's can increase propulsive force with visual biofeedback, suggesting the presence of a propulsive reserve. Though stride length did not significantly change, clinically meaningful improvements were observed. Targeting push-off force through visual biofeedback may offer a potential rehabilitation technique to enhance gait performance in Persons with Parkinson's. Future studies could explore the long-term efficacy of this intervention and investigate additional strategies to improve gait in Parkinson's disease.

Combining physical & cognitive training with iPSC-derived dopaminergic neuron transplantation promotes graft integration & better functional outcome in parkinsonian marmosets

Parkinson's disease (PD) is a relentlessly progressive and currently incurable neurodegenerative disease with significant unmet medical needs. Since PD stems from the degeneration of midbrain dopaminergic (DA) neurons in a defined brain location, PD patients are considered optimal candidates for cell replacement therapy. Clinical trials for cell transplantation in PD are beginning to re-emerge worldwide with a new focus on induced pluripotent stem cells (iPSCs) as a source of DA neurons since they can be derived from adult somatic cells and produced in large quantities under current good manufacturing practices. However, for this therapeutic strategy to be realized as a viable clinical option, fundamental translational challenges need to be addressed including the manufacturing process, purity and efficacy of the cells, the method of delivery, the extent of host reinnervation and the impact of patient-centered adjunctive interventions. In this study we report on the impact of physical and cognitive training (PCT) on functional recovery in the nonhuman primate (NHP) model of PD after cell transplantation. We observed that at 6 months post-transplant, the PCT group returned to normal baseline in their daily activity measured by actigraphy, significantly improved in their sensorimotor and cognitive tasks, and showed enhanced synapse formation between grafted cells and host cells. We also describe a robust, simple, efficient, scalable, and cost-effective manufacturing process of engraftable DA neurons derived from iPSCs. This study suggests that integrating PCT with cell transplantation therapy could promote optimal graft functional integration and better outcome for patients with PD.

Exploring Potential Predictors of Treadmill Training Effects in People With Parkinson Disease

OBJECTIVE

To explore the potential predictors of people with Parkinson disease (PD) who would benefit the most from treadmill training.

DESIGN

A cohort study.

SETTING

Medical university rehabilitation settings.

PARTICIPANTS

Seventy participants diagnosed of idiopathic PD.

INTERVENTIONS

Twelve sessions of treadmill training.

MAIN OUTCOME MEASURES

Hierarchical logistic regression models were used to explore significant predictors of the treadmill training effect with respect to 3 health domains: Unified Parkinson's Disease Rating Scales part III (UPDRS III); gait speed; Parkinson's Disease Questionnaire-39 (PDQ-39). A receiver operating characteristic (ROC) curve analysis was conducted to identify proper cut-off points for clinical use.

RESULTS

Male sex (adjusted odds ratio [OR]: 3.73, P=.036) significantly predicted the improvement of UPDRS III. Individuals with a slower baseline gait speed (cut-off: 0.92 m/s, adjusted OR: 14.06, P<.001) and higher baseline balance confidence measured by the Activity-specific Balance Confidence scale (cut-off: 84.5 points, adjusted OR: 4.66, P=.022) have greater potential to achieve clinically relevant improvements in gait speed. A poorer baseline PDQ-39 score (cut-off: 23.1, adjusted OR: 7.47, P<.001) predicted a greater quality of life improvement after treadmill training.

CONCLUSIONS

These findings provide a guideline for clinicians to easily identify suitable candidates for treadmill training. Generalization to more advanced patients with PD warrants further investigation.

[The benefits of exercise training for Parkinson's patients]

The French National Authority for Health and the World Health Organization issue recommendations on physical activity for Parkinson's disease patients. But what about the scientific literature? Here, we look at a 2014 literature review that shows the value of exercise retraining for these patients.

Physical exercise and its effects on people with Parkinson's disease: Umbrella review

INTRODUCTION

Parkinson's disease is neurodegenerative, complex and progressive, manifesting in a slow and irreversible way. Physical exercise has been proposed as therapeutic alternative to people with Parkinson´s disease.

OBJECTIVE

To synthesize knowledge about the effects of physical exercise on people with Parkinson´s Disease as presented by published systematic reviews.

METHODS

Nine electronic databases and two grey literature databases were searched for systematic reviews reporting the effects of physical exercises on people with Parkinson´s Disease. Searches involved a two-phase process, by, at least, two independent reviewers. Methodological quality of the included systematic reviews was assessed using AMSTAR-2.

RESULTS

From 2,122 systematic reviews, 139 were included. Motor outcomes were assessed in 91% of the studies, with balance being the most studied. Non-motor outcomes were assessed in 68% of the studies, with emphasis on quality of life. Physical exercises were classified into five categories: aerobic exercises, strength, combined, sensorimotor activities and other activity protocols. Findings of the systematic reviews suggest that all exercise categories can be prescribed to improve balance and mobility, while combined exercises, strength, and specific activities improve both motor and non-motor outcomes, and aerobic exercise and sensorimotor activities improve motor outcomes.

CONCLUSION

Current evidence from systematic reviews suggests that physical exercises impacts both motor and non-motor outcomes in people with Parkinson´s Disease. Limits in evidence provided by the systematic reviews were related to methodological issues and to the description of the interventions and must be considered to improve decision-making and clinical application.

Directed connectivity in Parkinson's disease patients during over-ground and treadmill walking

Treadmill walking is considered a useful therapeutic tool for improving gait in Parkinson's disease (PD) patients. The study investigated the role of top-down, frontal-parietal versus bottom-up parietal-frontal networks, during over-ground and treadmill walking in PD and control subjects, using functional connectivity. To this end, EEG was recorded simultaneously, during a ten-minute period of continuous walking either over-ground or on a treadmill, in thirteen PD patients and thirteen age-matched controls. We evaluated EEG directed connectivity, using phase transfer entropy in three frequency bands: theta, alpha and beta. PD patients showed increased top-down connectivity during over-ground compared with treadmill walking, in the beta frequency range. Control subjects showed no significant differences in connectivity between the two walking conditions. Our results suggest that in PD patients, OG walking was associated with increased allocation of attentional resources, compared with that on the TL. These functional connectivity modulations may shed further light on the mechanisms underlying treadmill versus overground walking in PD.

Intermittent theta-burst stimulation combined with physical therapy as an optimal rehabilitation in Parkinson's disease: study protocol for a randomised, double-blind, controlled trial

BACKGROUND

First-line rehabilitative strategies to improve motor deficits are based on functional training (physical or occupational therapy), which has been demonstrated to facilitate neural reorganisation. Accumulating evidence suggests that non-invasive brain stimulation techniques, such as repetitive TMS (rTMS), may enhance neuroplasticity, thereby facilitating neural reorganisation and recovery from Parkinson's disease. Evidence also shows that intermittent theta-burst stimulation (iTBS) can improve motor function and quality of life in patients by promoting the excitability and neural remodelling of cerebral cortex. We aimed to combine iTBS stimulation with physiotherapy to improve the rehabilitation effect compared to physiotherapy alone in patients with Parkinson's disease.

METHODS

This randomised, double-blind clinical trial will enrol 50 Parkinson's disease patients aged 45-70 years with Hoehn and Yahr scale scores of 1-3. Patients are randomly assigned to either the iTBS + physiotherapy or sham-iTBS + physiotherapy group. The trial consists of a 2-week double-blind treatment period and a 24-week follow-up period. iTBS and sham-iTBS will be administered twice daily for 10 days based on physiotherapy. The primary outcome will be the third part of Movement Disorders-Unified Parkinson's Disease Rating Scale (MDS-UPDRS III) from the baseline to the first 2 days following completion hospitalised intervention. The secondary outcome will be 39-item Parkinson's Disease Questionnaire (PDQ-39) at 4 weeks, 12 weeks and 24 weeks after intervention. Tertiary outcomes are clinical evaluations and mechanism study outcomes such as NMSS, 6MWD, 10MT, TUG, BBS, MRI, and EEG, the length of time between the drug needs to be adjusted when symptoms fluctuate.

DISCUSSION

The aim of this study is to demonstrate that iTBS can promote overall function and quality of life in Parkinson's disease patients using physiotherapy and that this efficacy may be associated with altered neuroplasticity in exercise-related brain regions. The iTBS combined with physiotherapy training model will be evaluated during a 6-month follow-up period. With significant improvement in quality of life and motor function, iTBS combined with physiotherapy can be considered as a first-line rehabilitation option for Parkinson's disease. The potential of iTBS to enhance neuroplasticity in the brain should have a more positive impact in increasing the generality and efficiency of physiotherapy, improving the quality of life and overall functional status of patients with Parkinson's disease.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2200056581. Registered on 8 February 2022.

Acclimatization of force production during walking in persons with Parkinson's disease

Individuals with Parkinson's disease walk slowly, with short strides resulting in decreased mobility. Treadmill walking assessments are utilized to understand gait impairment in persons with Parkinson's disease and treadmill-based interventions to mobility have become increasingly popular. While walking on a treadmill, there is a reported initial acclimatization period where individuals adjust to the speed and dynamics of the moving belt before producing consistent walking patterns. It is unknown how much walking time is required for individuals with Parkinson's disease to acclimate to the treadmill. We investigated how spatiotemporal parameters and ground reaction forces changed during treadmill acclimatization. Twenty individuals with idiopathic Parkinson's (15 Males, 5 Females) walked for a five-minute treadmill session on an instrumented treadmill while motion capture data were collected. The measures of interest included ground reaction force measures (peak propulsive force, peak braking force, propulsive impulse, and braking impulse) and spatiotemporal measures (stride length, stride time, or double support time). Analyses demonstrated significantly increased propulsive impulse (p <.001) after the first minute, with no significant difference for the remaining minutes (p ≥ 0.395). There were no significant changes in the spatiotemporal measures (P =.065). These results quantify the stabilization of ground reaction force during the treadmill acclimatization period. Based on our findings, if steady-state gait is desired, we recommend participants walk for at least two minutes before data collection. Future clinical investigations should consider ground reaction force as sensitive parameters for evaluating gait in persons with Parkinson's disease in treadmill-based assessments or interventional therapies.

Exercise-Boosted Mitochondrial Remodeling in Parkinson's Disease

Parkinson's disease (PD) is a movement disorder characterized by the progressive degeneration of dopaminergic neurons resulting in dopamine deficiency in the striatum. Given the estimated escalation in the number of people with PD in the coming decades, interventions aimed at minimizing morbidity and improving quality of life are crucial. Mitochondrial dysfunction and oxidative stress are intrinsic factors related to PD pathogenesis. Accumulating evidence suggests that patients with PD might benefit from various forms of exercise in diverse ways, from general health improvements to disease-specific effects and, potentially, disease-modifying effects. However, the signaling and mechanism connecting skeletal muscle-increased activity and brain remodeling are poorly elucidated. In this review, we describe skeletal muscle-brain crosstalk in PD, with a special focus on mitochondrial effects, proposing mitochondrial dysfunction as a linker in the muscle-brain axis in this neurodegenerative disease and as a promising therapeutic target. Moreover, we outline how exercise secretome can improve mitochondrial health and impact the nervous system to slow down PD progression. Understanding the regulation of the mitochondrial function by exercise in PD may be beneficial in defining interventions to delay the onset of this neurodegenerative disease.

Treadmill training in Parkinson's disease is underpinned by the interregional connectivity in cortical-subcortical network

Treadmill training (TT) has been extensively used as an intervention to improve gait and mobility in patients with Parkinson's disease (PD). Regional and global effects on brain activity could be induced through TT. Training effects can lead to a beneficial shift of interregional connectivity towards a physiological range. The current work investigates the effects of TT on brain activity and connectivity during walking and at rest by using both functional near-infrared spectroscopy and functional magnetic resonance imaging. Nineteen PD patients (74.0 ± 6.59 years, 13 males, disease duration 10.45 ± 6.83 years) before and after 6 weeks of TT, along with 19 age-matched healthy controls were assessed. Interregional effective connectivity (EC) between cortical and subcortical regions were assessed and its interrelation to prefrontal cortex (PFC) activity. Support vector regression (SVR) on the resting-state ECs was used to predict prefrontal connectivity. In response to TT, EC analysis indicated modifications in the patients with PD towards the level of healthy controls during walking and at rest. SVR revealed cerebellum related connectivity patterns that were associated with the training effect on PFC. These findings suggest that the potential therapeutic effect of training on brain activity may be facilitated via changes in compensatory modulation of the cerebellar interregional connectivity.

Studying the Research-Practice Gap in Physical Therapies for Cerebral Palsy: Preliminary Outcomes Based on a Survey of Spanish Clinicians

The purpose of this work is to study the gap between the research evidence and the clinical practice in the physical rehabilitation of people with cerebral palsy. A review process was performed to (1) identify physical therapies to improve postural control in children with cerebral palsy and (2) determine the scientific evidence supporting the effectiveness of those therapies. A Likert-based survey addressing a total of 43 healthcare professionals involved in pediatric physical therapy departments in Spain was carried out. The discussion was mainly supported by studies of level I or II evidence (according to the Oxford scale). The search process yielded 50 studies reporting 16 therapies. A strong positive correlation between the most used treatments and elevated levels of satisfaction was found. Some well-known but not often used techniques, such as hippotherapy, were identified. The treatment with the highest degree of use and satisfaction-neurodevelopment therapy (Bobath)-and some emerging techniques, such as virtual reality, were also identified. The fact that there is a meaningful gap between clinical practice and the scientific evidence was confirmed. The identified gap brings a certain degree of controversy. While some classic and well-known therapies had poor levels of supporting evidence, other relatively new approaches showed promising results.

Multichannel Transcranial Direct Current Stimulation Combined With Treadmill Gait Training in Patients With Parkinson's Disease: A Pilot Study

Background

Gait problems are critical impairments in Parkinson's disease (PD) and are related to increased risk of fall and negatively impact activities of daily life. Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that can modify the cortical excitability of gait-related brain regions. In this study, we investigated whether multichannel tDCS with simultaneous treadmill gait training could improve gait in PD.

Methods

Twenty-four patients with PD were assigned randomly to a real or sham tDCS group. Before intervention, one patient of the real tDCS group was dropped out, leaving 23 patients to be analyzed in this study. Each patient underwent 30 min of treadmill gait training for 10 sessions over four consecutive weeks. Multichannel 4x1 tDCS was applied using five 6-cm-diameter round electrodes. One anode was placed on the CZ, and four cathodes were positioned symmetrically over the FZ, C5, C6, and PZ. Anodal tDCS (2mA) and sham tDCS were delivered for 20 min. The secondary outcomes were gait performance, as measured by the timed up and go test (TUG) and freezing of gait questionnaire (FOG-Q), and balance was assessed using the dynamic gait index (DGI), Berg balance scale (BBS), and functional reach test (FRT). Motor and non-motor performance of patients with PD were assessed using the Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS). Participants were assessed before the intervention, immediately after the intervention, and 4 weeks after completion of the intervention.

Results

The real tDCS group showed a significant improvement in the 10-m walk test, but the sham group did not. Among the secondary outcome measures, MDS-UPDRS part II, TUG, and BBS were improved only in the real tDCS group. Particularly, MDS-UPDRS part II showed a significant group*time interaction effect, indicating that real tDCS demonstrated a better effect on the activities of daily living patients with PD.

Conclusions

The results of this pilot study suggest that multichannel tDCS applied on the leg motor cortex during treadmill gait training is a safe and effective means to improve gait velocity in patients with PD. Additional rigorous, large-sample, multicenter, randomized controlled trials are needed to confirm the effect of tDCS as a therapeutic adjunct for gait rehabilitation of patients with PD.

Overground versus treadmill walking in Parkinson's disease: Relationship between speed and spatiotemporal gait metrics

BACKGROUND

Treadmills provide a safe and convenient way to study the gait of people with Parkinson's disease (PD), but outcome measures derived from treadmill gait may differ from overground walking.

OBJECTIVE

To investigate how the relationships between gait metrics and walking speed vary between overground and treadmill walking in people with PD and healthy controls.

METHODS

We compared 29 healthy controls to 27 people with PD in the OFF-medication state. Subjects first walked overground on an instrumented gait walkway, then on an instrumented treadmill at 85%, 100% and 115% of their overground walking speed. Average stride length and cadence were computed for each subject in both overground and treadmill walking.

RESULTS

Stride length and cadence both differed between overground and treadmill walking. Regressions of stride length and cadence on gait speed showed a log-log relationship for both overground and treadmill gait in both PD and control groups. The difference between the PD and control groups during overground gait was maintained for treadmill gait, not only when treadmill speed matched overground speed, but also with ± 15% variation in treadmill speed from that value.

SIGNIFICANCE

These results show that the impact of PD on stride length and cadence and their relationship to gait speed is preserved in treadmill as compared to overground walking. We conclude that a treadmill protocol is suitable for laboratory use in studies of PD gait therapeutics.

The effect of body weight-supported overground gait training for patients with Parkinson's disease: A retrospective case-control observational study

Objective

To evaluate the effects of body weight-supported overground gait training (BWSOGT) on motor abilities, such as gait and balance, in patients with Parkinson’s disease (PD).

Design

Retrospective case-controlled observational study with a 4-week follow-up.

Setting

Inpatient rehabilitation.

Participants

We selected 37 of 68 patients with PD. Inclusion criteria were (1) Hoehn & Yahr stage II–IV, (2) no medication adjustment during the study period, (3) at least 1 week since last medication adjustment, and (4) ability to walk more than 10 meters on their own. Exclusion criteria were (1) cerebrovascular disease or other complications affecting movement, (2) difficulty in measurement, (3) early discharge, (4) medication change during the study, and (5) development of complications.

Interventions

Patients were divided into two groups. Patients in Group I underwent 20 minutes of BWSOGT with a mobile hoist in addition to the standard exercises; Group II performed 20 minutes of gait training in place of BWSOGT. In both groups, training was performed for a total of 15 times/4 weeks.

Main outcome measure(s)

Participants were evaluated using the Unified Parkinson’s Disease Rating Scale total, part II, and part III; 10-m walk test; velocity; stride length; 6-minute walk test; timed up and go test; Berg Balance Scale; and freezing of gait before and after the intervention.

Results

There were significant decreases in the Unified Parkinson’s Disease Rating Scale total, part II, and part III in both groups; however, 6-minute walk test, timed up and go test, and freezing of gait results only improved in Group I.

Conclusions

BWSOGT for patients with PD improves gait ability and dynamic balance more than standard gait training.

Physical exercise increases the production of tyrosine hydroxylase and CDNF in the spinal cord of a Parkinson's disease mouse model

Previous research advocates that exercise is a non-pharmacological therapy for Parkinson's disease (PD). However, few studies have investigated the effects of exercise on central nervous system structures other than the nigrostriatal pathway by using PD animal models. This study investigated the effects of exercise on tyrosine hydroxylase (TH)- and cerebral dopamine neurotrophic factor (CDNF)-containing spinal-cord neurons. Male Swiss mice were divided into 4 groups: sedentary control (SEDCONT), exercise control (EXERCONT), sedentary Parkinson (SEDPD), and exercise Parkinson (EXERPD). The PD groups were submitted to a surgical procedure for stereotaxic bilateral injection of 6-hydroxydopamine into the striatum. TH- and CDNF-containing spinal-cord neurons were evaluated in all groups, using immunohistochemistry and western-blotting. TH content in the ventral horn differed notably between the SEDPD and EXERPD groups. CDNF content was highest in the EXERPD group. SEDPD and EXERPD groups differed the most, as shown by immunohistochemistry and western-blotting. The EXERPD group showed the most intense labeling in immunohistochemistry compared to the SEDCONT and EXERCONT groups. Therefore, we showed here that exercise increased the content of both TH and CDNF in the spinal-cord neurons of a bilateral PD mouse model. We may assume that the spinal cord is affected in a PD model, and therefore this central nervous system region deserves more attention from researchers dealing with PD.

Immediate effects of treadmill walking in individuals with Lewy body dementia and Huntington's disease

BACKGROUND

Treadmill training may improve gait disorders associated with neurodegenerative diseases. In Parkinson's disease (PD), treadmill training alters gait patterns after one session, and long-term training improves gait parameters, fall risk, and quality of life.

RESEARCH QUESTION

What is the feasibility and safety of using this intervention for people with Lewy body dementia (LBD) or Huntington's disease (HD)?

METHODS

In this observational study, 10 individuals with HD, 8 individuals with LBD, and 10 control individuals walked for 20 min on a treadmill using a speed dependent protocol starting at a slow comfortable speed and increasing incrementally toward their normal overground speed. Feasibility was determined by compliance to protocol and safety by no incidents of abnormal vital signs or expressions of distress. Changes in gait measures, Timed Up and Go (TUG) scores and quantitative motor function measures (Q-Motor; precision grasp force variability, finger and foot tapping frequency) before and after treadmill walking were analyzed using linear models.

RESULTS

Treadmill training is feasible and safe in LBD and HD; although, participants could not initiate treadmill walking at their comfortable overground speeds, and only 3 participants with HD were able to achieve their overground walking speed within the 20-minute session. No changes in gait measures, TUG times, and Q-Motor measures were found among LBD and HD participants after treadmill walking, although control participants demonstrated significant increases in several gait measures, and foot tap frequency (estimated difference = 0.290; p = 0.026).

SIGNIFICANCE

Longer and more frequent treadmill sessions may be needed to see gait and motor function effects in LBD and HD. Motor and cognitive impairments associated with these diseases may make them less amenable to the effects of treadmill training.

Body Weight Support Gait Training for Patients With Parkinson Disease: A Systematic Review and Meta-analyses

OBJECTIVE

To determine the effectiveness of body weight support (BWS) gait training to improve the clinical severity, gait, and balance in patients with Parkinson disease (PD).

DATA SOURCES

A literature search was conducted until July 2020 in MEDLINE, Physiotherapy Evidence Database, Cochrane Central Register of Controlled Trials, and Cumulative Index to Nursing and Allied Health Literature.

STUDY SELECTION

Randomized controlled trials that aimed at determining the effectiveness of physical activity interventions with BWS during gait training in patients with PD.

DATA EXTRACTION

The methodological quality of randomized controlled trials was assessed using the Cochrane risk of bias tool (RoB 2.0). Effect size (ES) and 95% confidence intervals [CIs] were calculated for the Unified Parkinson Disease Rating Scale (UPDRS), the UPDRS section III, the 6-minute walk test (6MWT), gait parameters (ie, velocity, cadence, stride length), and the Berg Balance Scale (BBS).

DATA SYNTHESIS

Twelve studies were included in the systematic review. The pooled ES for the effect of BWS on total UPDRS was -0.35 (95% CI, -0.57 to -0.12; I²=1.9%, P=.418), whereas for UPDRS III it was -0.35 (95% CI, -0.68 to -0.01; I²=66.4 %, P<.001). Furthermore, the pooled ES for 6MWT was 0.56 (95% CI, -0.07 to 1.18; I²=77.1%, P=.002), for gait velocity was 0.37 (95% CI, -0.10 to 0.84); I²=78.9%, P<.001), for cadence was 0.03 (95% CI, -0.25 to 0.30; I²=0.0%, P=.930), for stride length was 1.00 (95% CI, 0.23 to 1.78; I²=79.5%, P=.001), and for BBS was 0.65 (95% CI, 0.30, 0.99; I²=51.8%, P=.042).

CONCLUSIONS

Interventions with BWS could improve the general and motor clinical severity of patients with PD, as well as other parameters such as stride length and balance. However, the effect does not appear to be statistically significant in improving gait parameters such as velocity, cadence, and distance.

Effects of treadmill training on gait of elders with Parkinson's disease: a literature review

Parkinson's disease is the second most common neurodegenerative disorder in old age. Aging process for elders with Parkinson's disease can induce gait disturbances with more functional disabilities than for elders without the disease. Treadmill training as a therapy has resulted in notable effects on the gait of patients with Parkinson's disease and may be a resource for geriatric neurological rehabilitation. This review aimed to study the effects on gait after treadmill training in elderly patients with Parkinson's disease. The search was performed in the databases PubMed®, LILACS, PEDro and EMBASE, with the following keywords: "Parkinson's disease", "elderly", "treadmill training" and "gait evaluation". The quality of the studies included was assessed by PEDro Scale. Eleven studies met the inclusion and exclusion criteria. Eight studies were randomized, and only one did a follow-up. One can observe in this review that treadmill training with or without weight support (at least 20 minutes, two to three times a week, with progressive increase of loads, for minimum of 6 weeks) in elderly patients with the Parkinson's disease was effective to improve gait. In addition, both were considered safe (since some studies described the use of belts, even in unsupported training) and can be associated with therapies complementary to gait, such as repetitive transcranial magnetic stimulation, visual cues or anodal transcranial direct current stimulation. Treadmill training in elderly patients with Parkinson's disease is an intervention that improves gait outcomes, but further studies are required for better proofs.

A multi-modal virtual reality treadmill intervention for enhancing mobility and cognitive function in people with multiple sclerosis: Protocol for a randomized controlled trial

BACKGROUND

Gait and cognitive impairments are common in individuals with Multiple Sclerosis (MS) and can interfere with everyday function. Those with MS have difficulties executing cognitive tasks and walking simultaneously, a reflection of dual-task interference. Therefore, dual-task training may improve functional ambulation. Additionally, using technology such as virtual reality can provide personalized rehabilitation while mimicking real-world environments. The purpose of this randomized controlled trial is to establish the benefits of a combined cognitive-motor virtual reality training on MS symptoms compared to conventional treadmill training.

METHODS

This study will be a single-blinded, two arm RCT with a six-week intervention period. 144 people with MS will be randomized into a treadmill training alone group or treadmill training with virtual reality group. Both groups will receive 18 sessions of training while walking on a treadmill, with the virtual reality group receiving feedback from the virtual system. Primary outcome measures include dual-task gait speed and information processing speed, which will be measured prior to training, one-week post-training, and three months following training.

DISCUSSION

This study will provide insight into the ability of a multi-modal cognitive-motor intervention to reduce dual-task cost and to enhance information processing speed in those with MS. This is one of the first studies that is powered to understand whether targeted dual-task training can improve MS symptoms and increase functional ambulation. We anticipate that those in the virtual reality group will have a significantly greater increase in dual-task gait speed and information processing speed than those achieved via treadmill training alone.

Targeted Rhythmic Auditory Cueing During Treadmill and Overground Gait for Individuals With Parkinson Disease: A Case Series

BACKGROUND AND PURPOSE

Rhythmic auditory cueing and treadmill walking can improve spatiotemporal gait parameters through entrainment of movement patterns. Careful selection of cue frequencies is necessary if treadmill walking is to be employed, because cadence and step length are differentially affected by walking on a treadmill and overground. The purpose of this study was to describe the treatment of gait impairments for individuals with Parkinson disease, using strategically selected rhythmic auditory cue frequencies on both a treadmill and overground.

CASE DESCRIPTION

Three individuals with Hoehn & Yahr stage 2 Parkinson disease participated in this case series.

INTERVENTION

All participants completed 6 weeks of gait training, in which each session employed rhythmic auditory cueing during treadmill-based gait training followed by overground gait training. We provided targeted rhythmic auditory cueing with a metronome set to 85% and 115% of their self-selected cadence for treadmill and overground training, respectively. We performed clinical tests of gait and balance prior to, midway, and following training, and at a 3-month follow-up.

OUTCOMES

All participants improved overground gait speed (participant 1: +0.27 m/s; participant 2: +0.20 m/s; and participant 3: +0.18 m/s) and stride length (15.7 ± 4.17 cm) with small changes to cadence. Likewise, there were only small changes in balance.

DISCUSSION

We hypothesize that the large improvements in gait speed are due to the concomitant increases in stride length. Further research is needed to test the effect of targeted rhythmic auditory cueing during treadmill and overground gait.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A309).

Treadmill walking alters stride time dynamics in Parkinson's disease

BACKGROUND

Treadmill training may be used to improve gait rhythmicity in people with Parkinson's disease. Treadmills, however, alter dynamical stride time fluctuations in healthy adults in a manner that mimics pathologic states, indicating the stride-to-stride fluctuations that characterize healthy gait are constrained. It is unclear if treadmills similarly alter dynamic gait properties in Parkinson's disease.

RESEARCH QUESTION

Do stride time fractal dynamics in individuals with Parkinson's disease differ between treadmill and overground walking?

METHODS

Fifteen participants with Parkinson's disease and 15 healthy age-similar adults walked for 6 min in a conventional overground condition and on a treadmill while wearing inertial measurement units. Gait speed, stride times and stride time variability were measured. Fractal exponents (α) were computed with adaptive fractal analysis. Inferential statistics were analyzed with mixed model analyses of variance and post hoc simple effects tests.

RESULTS

Mean gait speeds decreased and stride times increased on the treadmill but did not differ between the Parkinson's and control groups. Stride time variability was greater in the Parkinson's than control group in both conditions. Most relevant to our research question, stride time fractal exponents were greater on the treadmill (mean α = .910) than overground (mean α = .797) in individuals with Parkinson's disease, but not in healthy controls.

SIGNIFICANCE

The fractal scaling exponent α emanating from stride time fluctuations during treadmill walking increased toward a 1/f signal of α = 1.0 that has been interpreted as an optimal structural variability for gait. The clinical implication is that treadmill training may promote more efficient walking dynamics in people with Parkinson's disease than conventional overground training.

The effect of fatigue on balance performance in Parkinson's disease

Introduction

Balance loss and falls are a common and multifactorial finding in persons with Parkinson's Disease (pwPD). Objective fatigability is thought to contribute to falls in other neurologic conditions, but its impact on balance in pwPD is not known. The two-fold purpose of this study was to: 1) establish that a 6-minute walk (6MW_Fast) is a stimulus to subjective fatigue for pwPD; and, 2) determine if the Mini Balance Evaluation Systems Test (MBT) is sensitive to change that was induced by a fatiguing condition.

Methods

Using a randomized crossover design, 19 research participants performed a Mini Balance Evaluation Systems Test (MBT) before and after either a ‘fast’ 6-minute walk (6MW_Fast) to induce fatigue or a 6-minute rest.

Results

VASF scores increased after the 6MW_Fast. Total MBT scores in research participants with Modified Hoehn and Yahr (H&Y) scores of 3.0 and above differed significantly before and after the ‘fast’ 6-minute walk (p = .007, n = 9) while participants with H&Y scores of 1.5 to 2.5 (p = .084, n = 10) did not, suggesting that more disabled pwPD were more likely to experience fatigability that interfered with balance.

Conclusions

A 6MW_Fast is a sufficient stimulus to induce subjective fatigue in pwPD and to decrease total MBT scores for more disabled pwPD. Balance evaluations should occur when pwPD are in fatigued and unfatigued states to determine whether fatigue has an impact on balance performance.

•

Both subjective fatigue and objective fatigability can occur in Parkinsons Disease (PD).

•

Objective fatigability may be a factor in balance impairment in persons with PD.

•

Balance assessments in PD should be made with the patient in both a fatigued and non fatigued state.

What and How Can Physical Activity Prevention Function on Parkinson's Disease?

Aim

This study was aimed at investigating the effects and molecular mechanisms of physical activity intervention on Parkinson's disease (PD) and providing theoretical guidance for the prevention and treatment of PD.

Methods

Four electronic databases up to December 2019 were searched (PubMed, Springer, Elsevier, and Wiley database), 176 articles were selected. Literature data were analyzed by the logic analysis method.

Results

(1) Risk factors of PD include dairy products, pesticides, traumatic brain injury, and obesity. Protective factors include alcohol, tobacco, coffee, black tea, and physical activity. (2) Physical activity can reduce the risk and improve symptoms of PD and the beneficial forms of physical activity, including running, dancing, traditional Chinese martial arts, yoga, and weight training. (3) Different forms of physical activity alleviate the symptoms of PD through different mechanisms, including reducing the accumulation of α-syn protein, inflammation, and oxidative stress, while enhancing BDNF activity, nerve regeneration, and mitochondrial function.

Conclusion

Physical activity has a positive impact on the prevention and treatment of PD. Illustrating the molecular mechanism of physical activity-induced protective effect on PD is an urgent need for improving the efficacy of PD therapy regimens in the future.

The benefits and mechanisms of exercise training for Parkinson's disease

Parkinson's disease (PD) is a significantly progressive neurodegenerative disease characterised by both motor and nonmotor disorders. The main pathological characteristics of PD consist of the loss of dopaminergic neurons and the formation of alpha-synuclein-containing Lewy bodies in the substantia nigra. Currently, the main therapeutic method for PD is anti-Parkinson medications, including levodopa, madopar, sirelin, and so on. However, the effect of pharmacological treatment has its own limitations, the most significant of which is that the therapeutic effect of dopaminergic treatments gradually diminishes with time. Exercise training, as an adjunctive treatment and complementary therapy, can improve the plasticity of cortical striatum and increase the release of dopamine. Exercise training has been proven to effectively improve motor disorders (including balance, gait, risk of falls and physical function) and nonmotor disorders (such as sleep impairments, cognitive function and quality of life) in PD patients. In recent years, various types of exercise training have been used to treat PD. In this review, we summarise the exercise therapy mechanisms and the protective effects of different types of exercise training on PD patients.

Occupational therapy with Nordic walking and therapeutic touch: A pilot study for multidisciplinary rehabilitation in Parkinson's disease

BACKGROUND

Physical exercise combined with occupational therapy (OT) can lead to a global improvement in personal well-being.

OBJECTIVE

To assess in PD patients: 1) if a rehabilitation program involving OT, Nordic walking (NW) and therapeutic touch (TT) yields motor/non-motor benefits; 2) if the time collocation of OT within the program influences results.

METHODS

This is a pilot study on 17 PD patients undergoing a 10-week rehabilitation program consisting of OT, NW and TT. Patients were randomized to receive OT in the first [Group 1, n = 8] vs. last five weeks [Group 2, n = 9] of the program. Scales (MMSE, FAB, BDI, UPDRS II and III, PDQ39 and AES-S) and 6MWT, Gait speed and length were assessed at three time-points.

RESULTS

Thirteen out of 17 patients were analyzed. 6MWT, Gait speed and length improved in time without between-group differences (p < 0.05) as did UPDRII, UPDRSIII, FAB and PDQ39 (p < 0.05). Baseline UPDRS II and III significantly determined Δ6MWT (adjusted R2 = 0.6738) and ΔGAIT speed (R2 = 0.6746) at multiple regression, while ΔGAIT length showed the best regression (adjusted R2 = 0.8247) with impact of age, gender and baseline PDQ39 (ADL and cognition dimensions).

CONCLUSIONS

Multidisciplinary rehabilitation including OT can improve motor and non-motor conditions in PD patients. The OT time-collocation at beginning or end of the rehabilitation program does not significantly affect results.

A Systematic Review of Rehabilitation for Corticobulbar Symptoms in Adults with Huntington's Disease

Background:

Corticobulbar symptoms have been reported in all stages of Huntington’s disease (HD); aspiration pneumonia associated with swallowing impairment has been identified as the most common cause of death. Whilst recent research has described positive effects of corticobulbar rehabilitation in other neurodegenerative conditions, it is unclear if this is similarly effective in HD. Preliminary evidence in corticospinal rehabilitation has revealed physical therapy and exercise could be beneficial for individuals with HD.

Objective:

This systematic review will explore the literature relative to rehabilitation of corticobulbar symptoms in adults with HD.

Methods:

Two investigators independently searched relevant electronic databases for literature related to corticobulbar rehabilitation in HD, published in English until October 2019. Included studies were critically appraised using the Oxford Centre for Evidence-based Medicine Levels of Evidence, Cochrane Risk of Bias Tool and Scottish Intercollegiate Guidelines Network checklists. Study outcomes included measurements of function, quality of life or neuromuscular physiology.

Results:

Seventy-seven publications were screened with eight studies meeting the inclusion criteria – two randomised control trials and six intervention studies. Validated and objective outcome measures of corticobulbar symptoms were infrequently used. There was a high risk of bias identified in 7/8 studies. The data suggested positive clinical outcomes, no adverse effects and no deterioration observed across longitudinal studies.

Conclusions:

This systematic review documented a lack of high-quality evidence to support the use of rehabilitation to treat corticobulbar symptoms in HD. However, the suggestion of potential positive effects based on available, albeit limited, studies provides justification for further research in this area.

Effects of Fatigue on Balance in Individuals With Parkinson Disease: Influence of Medication and Brain-Derived Neurotrophic Factor Genotype

BACKGROUND AND PURPOSE

Because falls can have deleterious consequences, it is important to understand the influence of fatigue and medications on balance in persons with Parkinson disease (PD). Thus, the purpose of this study was to investigate the effects of fatigue on balance in individuals with PD. Because brain-derived neurotrophic factor (BDNF) has been shown to be related to motor performance, we also explored its role.

METHODS

A total of 27 individuals (age = 65.4 ± 8.1 years; males = 14, females = 13) with neurologist-diagnosed PD with 13 genotyped for BDNF as Val66Val, 11 as Val66Met, 2 as Met66Met (1 refused). Participants were tested both on and off medication, 1 week apart. On both days, they completed a pre- and posttest separated by a fatiguing condition. Factorial analyses of variance were performed for the following balance domains: (1) anticipatory postural responses; (2) adaptive postural responses; (3) dynamic balance; (4) sensory orientation; and (5) gait kinematics. For BDNF, t-tests were conducted comparing genotype for the pre-post difference scores in both the on and off medication states.

RESULTS

There were no interactions between time (pre- and postintervention) and medication for any of the domains (Ps ≥ 0.187). Participants with BDNF Met alleles were not significantly different from Val66Val participants in balance (Ps ≥ 0.111) and response to a fatiguing condition (Ps ≥ 0.070).

DISCUSSION AND CONCLUSIONS

Fatigue does not appear to have a detrimental effect on balance, and there was not a differential effect of medication in individuals with PD. These results also indicate that participants with a BDNF Met allele did not have a greater decay in function after a fatiguing condition.Video Abstract available for more insights from the authors (see Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A196).

Effects of treadmill training on the balance, functional capacity and quality of life in Parkinson’s disease: A randomized clinical trial

Background

There is growing evidence that exercise modalities have considerable effects on Parkinson’s disease (PD). This trial aimed to provide a more detailed viewpoint of short-term and long-term treadmill training (TT) effects on some motor and non-motor features of PD.

Methods

In this prospective, randomized, single-blind clinical trial, 20 mild to moderate PD patients, admitted in Rasoul-e-Akram hospital in Tehran, Iran, were randomly allocated in case (11) and control (9) groups. Treadmill intervention was performed at moderate intensity with 60% of heart rate reserved (HRR) in two 30-min sessions/week for a duration of 10 weeks. Both the groups were evaluated for three times; at the baseline, 2 months later and then 2 months after the second evaluation. We assigned the Timed Up and Go test (TUG), 6-min walk test (6MW), and the SF-8 healthy questionnaire, for assessment of balance, functional capacity, and Quality of life (QoL), respectively.

Results

Balance and functional capacity were significantly improved in the case group after the intervention (TUG p-value: 0.003, 6MW p-value: 0.003). Moreover, the long-term analysis revealed significant results as well (TUG p-value: 0.001, 6MW p-value: 0.004). Mental condition’s scores of SF-8 in cases were not statistically different in short-term follow-up (F/U). However, analysis illustrated p-value: 0.016 for long-term assessment. The intervention induced significant changes in physical condition’s scores in both of the F/Us (PC p-value: 0.013).

Conclusions

This study provides evidence that a TT of mild to moderate intensity has significant and persistent benefits for the balance, functional capacity, and QoL in PD.

Comparison of the Effect of 8-Week Rebound Therapy-Based Exercise Program and Weight-Supported Exercises on the Range of Motion, Proprioception, and the Quality of Life in Patients with Parkinson's Disease

Introduction

Parkinson's disease (PD) is a chronic, progressive disorder that mainly affects the central nervous system and, consequently, the patient's functional status. This study aimed to compare the effect of 8-week rebound therapy-based exercise program and weight-supported exercises on the range of motion, proprioception, and the quality of life in patients with PD.

Methods

Twenty patients were randomly divided into two equal groups of weight-bearing exercises and rebound exercise with no significant differences in age, weight, and height. The variables of the range of motion, proprioception, and the quality of life were assessed in pre- and posttest. Data were analyzed using repeated measure ANOVA and t-test at a significant level of P < 0.05.

Results

All of the variables in the two groups were significantly improved after 8 weeks of exercise, whereas the improvement rate in the rebound therapy group was more than the weight-bearing exercises group in range of motion (134.60 ± 13.22 vs. 118.38 ± 12.48), proprioception (7.60 ± 3.22 vs. 10.38 ± 2.48), and the quality of life (147.60 ± 13.22 vs. 118.38 ± 12.48) of the patients (P < 0.001 for all variables).

Conclusions

Given that both rebound and weight-supported exercises are effective on improving the range of motion, proprioception, and the quality of life of people with PD, it is recommended that the benefits of these exercises to be used in physical rehabilitation programs. However, rebound therapy exercises have had a greater effect on people with PD, and it seems better to use these exercises more than others.

Alpha-synuclein at the nexus of genes and environment: the impact of environmental enrichment and stress on brain health and disease

Accumulation of alpha‐synuclein protein aggregates is the hallmark neuropathologic feature of synucleinopathies such as Parkinson’s disease. Rare point mutations and multiplications in SNCA, the gene encoding alpha‐synuclein, as well as other genetic alterations are linked to familial Parkinson’s disease cases with high penetrance and hence constitute major genetic risk factors for Parkinson’s disease. However, the preponderance of cases seems sporadic, most likely based on a complex interplay between genetic predispositions, aging processes and environmental influences. Deciphering the impact of these environmental factors and their interactions with the individual genetic background in humans is challenging and often requires large cohorts, complicated study designs, and longitudinal set‐ups. In contrast, rodent models offer an ideal system to study the influence of individual environmental aspects under controlled genetic background and standardized conditions. In this review, we highlight findings from studies examining effects of environmental enrichment mimicking stimulation of the brain by its physical and social surroundings as well as of environmental stressors on brain health in the context of Parkinson’s disease. We discuss possible internal molecular transducers of such environmental cues in Parkinson’s disease rodent models and emphasize their potential in developing novel avenues to much‐needed therapies for this still incurable disease.

This article is part of the Special Issue “Synuclein”

Body Weight Support Combined With Treadmill in the Rehabilitation of Parkinsonian Gait: A Review of Literature and New Data From a Controlled Study

Background: Gait disorders represent disabling symptoms in Parkinson's Disease (PD). The effectiveness of rehabilitation treatment with Body Weight Support Treadmill Training (BWSTT) has been demonstrated in patients with stroke and spinal cord injuries, but limited data is available in PD. Aims: The aim of the study is to investigate the efficacy of BWSTT in the rehabilitation of gait in PD patients. Methods: Thirty-six PD inpatients were enrolled and performed rehabilitation treatment for 4-weeks, with daily sessions. Subjects were randomly divided into two groups: both groups underwent daily 40-min sessions of traditional physiokinesitherapy followed by 20-min sessions of overground gait training (Control group) or BWSTT (BWSTT group). The efficacy of BWSTT was evaluated with clinical scales and Computerized Gait Analysis (CGA). Patients were tested at baseline (T0) and at the end of the 4-weeks rehabilitation period (T1). Results: Both BWSTT and Control groups experienced a significant improvement in clinical scales as FIM and UPDRS and in gait parameters for both interventions. Even if we failed to detect any statistically significant differences between groups in the different clinical and gait parameters, the intragroup analysis captured a specific pattern of qualitative improvement associated to cadence and stride duration for the BWSTT group and to the swing/stance ratio for the Control group. Four patients with chronic pain or anxious symptoms did not tolerate BWSTT. Conclusions: BWSTT and traditional rehabilitation treatment are both effective in improving clinical motor functions and kinematic gait parameters. BWSTT may represent an option in PD patients with specific symptoms that limit traditional overground gait training, e.g., severe postural instability, balance disorder, orthostatic hypotension. BWSTT is generally well-tolerated, though caution is needed in subjects with chronic pain or with anxious symptoms. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT03815409.

Motor Learning Deficits in Parkinson's Disease (PD) and Their Effect on Training Response in Gait and Balance: A Narrative Review

Parkinson's disease (PD) is a neurological disorder traditionally associated with degeneration of the dopaminergic neurons within the substantia nigra, which results in bradykinesia, rigidity, tremor, and postural instability and gait disability (PIGD). The disorder has also been implicated in degradation of motor learning. While individuals with PD are able to learn, certain aspects of learning, especially automatic responses to feedback, are faulty, resulting in a reliance on feedforward systems of movement learning and control. Because of this, patients with PD may require more training to achieve and retain motor learning and may require additional sensory information or motor guidance in order to facilitate this learning. Furthermore, they may be unable to maintain these gains in environments and situations in which conscious effort is divided (such as dual-tasking). These shortcomings in motor learning could play a large part in degenerative gait and balance symptoms often seen in the disease, as patients are unable to adapt to gradual sensory and motor degradation. Research has shown that physical and exercise therapy can help patients with PD to adapt new feedforward strategies to partially counteract these symptoms. In particular, balance, treadmill, resistance, and repeated perturbation training therapies have been shown to improve motor patterns in PD. However, much research is still needed to determine which of these therapies best alleviates which symptoms of PIGD, the needed dose and intensity of these therapies, and long-term retention effects. The benefits of such technologies as augmented feedback, motorized perturbations, virtual reality, and weight-bearing assistance are also of interest. This narrative review will evaluate the effect of PD on motor learning and the effect of motor learning deficits on response to physical therapy and training programs, focusing specifically on features related to PIGD. Potential methods to strengthen therapeutic effects will be discussed.

Treadmill training may be an effective form of task-specific training for improving mobility in people with Parkinson's disease and multiple sclerosis: a systematic review and meta-analysis

BACKGROUND

Task-specific training is an effective form of rehabilitation for improving mobility in neurological conditions. However, it remains unclear if task-specific training is effective in people with progressive disease.

OBJECTIVE

To establish the efficacy of task-specific training on the mobility of individuals with progressive neurological conditions.

DATA SOURCES

Electronic databases MEDLINE, EMBASE, CINAHL and Cochrane Database of Systematic Reviews.

STUDY ELIGIBILITY CRITERIA

Randomised controlled trials investigating the effect of task-specific training on mobility and falls rate in individuals with progressive neurological conditions.

STUDY APPRAISAL/SYNTHESIS METHODS

Risk of bias of individual studies was assessed using the Physiotherapy Evidence Database (PEDro) Scale. Mean differences (MD) and 95% confidence intervals were calculated and combined in meta-analysis.

RESULTS

Analysis of 16 trials found treadmill training improved comfortable walking velocity (m/second) in people with Parkinson's disease (MD 0.21m/second, 95%CI 0.15 to 0.27) and multiple sclerosis (MD 0.36m/second, 95%CI 0.20 to 0.52). Treadmill training improved stride length (m) (MD 0.12m, 95%CI 0.02 to 0.23) and step length (m) (MD 0.12m, 95%CI 0.01 to 0.23) in people with Parkinson's disease and walking endurance in people with multiple sclerosis (MD 26.53m, 95%CI 12.23 to 40.84). Treadmill training had no effect on cadence and did not improve walking endurance in Parkinson's disease. Over-ground walking did not improve mobility in Parkinson's disease or multiple sclerosis.

LIMITATIONS

Study sample sizes were small and findings must be interpreted with caution.

CONCLUSION

Treadmill training may be effective for improving mobility in people with Parkinson's disease and multiple sclerosis. The effectiveness of over-ground walking is uncertain.

SYSTEMATIC REVIEW PROSPERO REGISTRATION NUMBER

CRD42016047334.

Effect of virtual reality training on walking distance and physical fitness in individuals with Parkinson's disease

OBJECTIVE

To evaluate the effects of gait training with virtual reality (VR) on walking distance and physical fitness in individuals with Parkinson's Disease (PD).

METHODS

Thirty-seven individuals with PD participated in this prospective, randomized, controlled clinical trial. They were randomly allocated to a control group submitted to conventional training (n = 12), a treadmill group submitted to gait training on a treadmill (n = 13) and a VR group submitted to gait training using the XboxTM (n = 12). Clinical measures, gait variables and the Six-Minute Walk Test (6MWT) were evaluated: pre-intervention, after one intervention session, post-intervention and follow up (30 days after intervention).

RESULTS

The VR and treadmill groups travelled longer distances on the 6MWT and had faster gait speed in comparison to the control group. The VR and treadmill groups demonstrated an increase in pre-6MWT HR. The VR group had more intense HR after the first session and throughout training, but these gains were not maintained at the follow-up.

CONCLUSION

The present findings demonstrate that gait training with a VR program is as effective as treadmill training with regard to gains in walking distance and improvements in temporal gait variables in individuals with PD.

Effect of Treadmill Walking on Leg Muscle Activation in Parkinson's Disease

Treadmills are often used as rehabilitation devices to improve gait in Parkinson's disease (PD). Kinematic differences between treadmill and overground gait have been reported. However, electromyographic (EMG) patterns during treadmill and overground walking have not been systematically compared. The aim of this study was to assess the effects of treadmill gait on the magnitude of the EMG activity of the lower limb muscles in PD. We measured EMG activity of the tibialis anterior, gastrocnemius medialis, vastus lateralis, and biceps femoris of nine individuals with PD and nine healthy matched controls. Comparisons between walking overground with walking on a treadmill and with walking with a treadmill simulator were carried out. The treadmill simulator is a device that simulates treadmill conditions with the exception of the belt. Our results have shown that treadmill walking is associated with several EMG differences compared with overground walking. The key finding of the study is that coactivation of the thigh muscles was significantly decreased (37%; p = 0.008) in PD subjects when walking on the treadmill in comparison with overground walking. The changes observed in the coactivation level may be related to the belt movement, since no changes were reported during walking with the treadmill simulator. Understanding the differences between treadmill and overground gait as well as the mechanisms that result in improvement of gait disturbances may optimize rehabilitative protocols for patients with PD.

Treadmill walking reduces pre-frontal activation in patients with Parkinson's disease

BACKGROUND

Among patients with Parkinson's disease (PD), gait is typically disturbed and less automatic. These gait changes are associated with impaired rhythmicity and increased prefrontal activation, presumably in an attempt to compensate for reduced automaticity.

RESEARCH QUESTION

We investigated whether during treadmill walking, when the pace is determined and fixed, prefrontal activation in patients with PD is lower, as compared to over-ground walking.

METHODS

Twenty patients with PD (age: 69.8 ± 6.5 yrs.; MoCA: 26.9 ± 2.4; disease duration: 7.9 ± 4.2 yrs) walked at a self-selected walking speed over-ground and on a treadmill. A wireless functional near infrared spectroscopy (fNIRS) system measured prefrontal lobe activation, i.e., oxygenated hemoglobin (Hb02) in the pre-frontal area. Gait was evaluated using 3D-accelerometers attached to the lower back and ankles (Opal™, APDM). Dynamic gait stability was assessed using the maximum Lyapunov exponent to investigate automaticity of the walking pattern.

RESULTS

Hb02 was lower during treadmill walking than during over-ground walking (p = 0.001). Gait stability was greater on the treadmill, compared to over-ground walking, in both the anteroposterior and medio-lateral axes (p < 0.001).

SIGNIFICANCE

These findings support the notion that when gait is externally paced, prefrontal lobe activation is reduced in patients with PD, perhaps reflecting a reduced need for compensatory cognitive mechanisms.

Step length determines minimum toe clearance in older adults and people with Parkinson's disease

Reduced foot clearance when walking may increase the risk of trips and falls in people with Parkinson's disease (PD). Changes in foot clearance in people with PD are likely to be associated with temporal-spatial characteristics of gait such as walking slowly which evokes alterations in the temporal-spatial control of stepping patterns. Enhancing our understanding of the temporal-spatial determinants of foot clearance may inform the design of falls prevention therapies. Thirty-six people with PD and 38 age-matched controls completed four intermittent walks under two conditions: self-selected and fast gait velocity. Temporal-spatial characteristics of gait and foot (heel and toe) clearance outcomes were obtained using an instrumented walkway and 3D motion capture, respectively. A general linear model was used to quantify the effect of PD and gait velocity on gait and foot clearance. Regression evaluated the temporal and spatial gait predictors of minimum toe clearance (MTC). PD walked slower regardless of condition (p = .016) and tended to increase their step length to achieve a faster gait velocity. Step length and the walk ratio consistently explained the greatest proportion of variance in MTC (>28% and >33%, respectively) regardless of group or walking condition (p < .001). Our results suggest step length is the primary determinant of MTC regardless of pathology. Interventions that focus on increasing step length may help to reduce the risk of trips and falls during gait, however, clinical trials are required for robust evaluation.

Evidence for Differential Effects of 2 Forms of Exercise on Prefrontal Plasticity During Walking in Parkinson's Disease

BACKGROUND

In a randomized control trial conducted in patients with Parkinson's disease, a treadmill training program combined with virtual reality that targeted motor and cognitive aspects of safe ambulation led to fewer falls, compared with treadmill training alone.

OBJECTIVE

To investigate if the 2 types of training differentially affected prefrontal activation and if this might explain differences in fall rates after the intervention.

METHODS

Sixty-four patients with Parkinson's disease were randomized into the treadmill training arm (n = 34, mean age 73.1 ± 1.1 years, 64% men, disease duration 9.7 ± 1.0 years) or treadmill training with virtual reality arm (n = 30, mean age 70.1 ± 1.3 years, 71% men, disease duration 8.9 ± 1.1 years). Prefrontal activation during usual, dual-task, and obstacle negotiation walking was assessed before and after 6 weeks of training, using a functional near-infrared spectroscopy system.

RESULTS

Treadmill training with and without virtual reality reduced prefrontal activation during walking ( P < .001), with specific interactions related to training arm ( P = .01), lateralization ( P = .05), and walking condition ( P = .001). For example, among the subjects who trained with treadmill training alone, prefrontal activation during dual-task walking and obstacle negotiation increased after training, while in the combined training arm, activation decreased.

CONCLUSIONS

Prefrontal activation during usual and during more challenging walking conditions can be altered in response to 2 different types of training. The addition of a cognitive training component to a treadmill exercise program apparently modifies the effects of the training on the magnitude and lateralization of prefrontal activation and on falls, extending the understanding of the plasticity of the brain in PD.

Instrumental or Physical-Exercise Rehabilitation of Balance Improves Both Balance and Gait in Parkinson's Disease

We hypothesised that rehabilitation specifically addressing balance in Parkinson's disease patients might improve not only balance but locomotion as well. Two balance-training protocols (standing on a moving platform and traditional balance exercises) were assessed by assigning patients to two groups (Platform, n = 15, and Exercises, n = 17). The platform moved periodically in the anteroposterior, laterolateral, and oblique direction, with and without vision in different trials. Balance exercises were based on the Otago Exercise Program. Both platform and exercise sessions were administered from easy to difficult. Outcome measures were (a) balancing behaviour, assessed by both Index of Stability (IS) on platform and Mini-BESTest, and (b) gait, assessed by both baropodometry and Timed Up and Go (TUG) test. Falls Efficacy Scale-International (FES-I) and Parkinson's Disease Questionnaire (PDQ-8) were administered. Both groups exhibited better balance control, as assessed both by IS and by Mini-BESTest. Gait speed at baropodometry also improved in both groups, while TUG was less sensitive to improvement. Scores of FES-I and PDQ-8 showed a marginal improvement. A four-week treatment featuring no gait training but focused on challenging balance tasks produces considerable gait enhancement in mildly to moderately affected patients. Walking problems in PD depend on postural instability and are successfully relieved by appropriate balance rehabilitation. This trial is registered with ClinicalTrials.gov NCT03314597.