Objective: Resistance training, and other exercise regimens, is an overlooked and understudied effective therapy for patients with Parkinson’s disease. We provide cumulative evidence from multiple studies that support the effect of training on Parkinsonian symptoms, as quantified by the UPDRS III rating scale. We present a supplemental non-invasive and non-pharmacologic treatment that can tremendously improve the quality of life and provide a biochemical explanation as to why muscle building offsets the degenerative symptoms of Parkinson’s to delay the loss of fine motor control and prevent comorbidities associated with a sedentary lifestyle.

Background: Parkinson’s disease (PD) is a progressive neurological movement disorder, with idiopathic onset, that impairs activities of daily living with nearly 10 million individuals diagnosed worldwide according to the Parkinson’s Foundation. Underlying pathology manifests due to the loss of dopaminergic neurons within the substantia nigra pars compacta with a pathological hallmark of α-synuclein Lewy body inclusions. Classical parkinsonian motor features consist of resting tremors, cogwheel rigidity, bradykinesia/akinesia, and gait instability. Pathological advancement gradually debilitates fine-motor activities such as speech and eating. It is vital to continue developing therapies for neurodegenerative disorders such as PD to improve the quality of life in Parkinson’s patients. Typical treatment methodology encompasses levodopa with carbidopa drug courses, as well as deep brain stimulation (DBS) of the subthalamic nucleus (STN) and globus pallidus internus (GPi).

However, emerging clinical evidence has demonstrated exercise regimens, specifically resistance training, as an efficacious treatment method in improving motor coordination and mental acuity in Parkinson’s. Muscles working against a force activates muscle fiber hypertrophy, contributing to enlarged contractile myofibrils in skeletal muscle tissue which induces acute effects on functional mobility and thus improved motor outcomes. Increased muscle mass ultimately reduces PD symptoms and contributes to finer motor control. A biochemical perspective provides input onto how exercise leads to endorphins which, in turn, drives dopamine release to offset the dopaminergic deficit found in Parkinson’s patients.

Methods & Data Analysis: PubMed, Google Scholar, Web of Science, and Cochrane Library databases were utilized to collect manuscripts evaluating resistance training regimens. Relevant information extracted pertained to resistance training, exercise training variables (total sessions, duration, repetitions), therapy length, UPDRS type, and UPDRS III pre-mean and post-mean outcomes. Ten out of 17 potential papers met our search criteria. The seven papers excluded from this review did not specify a UPDRS III score before or after completing a resistance training regimen. We provide a retrospective systematic review to identify 10 prior research studies that reported UPDRS III scores before and after resistance training in Parkinson disease patients. Then, statistical analysis via a paired t-test was conducted to assess for differences in the mean UPDRS III score before and after resistance training for the 10 articles chosen.

Results: Upon reviewing 10 randomized control studies investigating the therapeutic effects of various resistance training routines on Parkinsonian symptoms, we found a significant decrease in UPDRS III (Unified Parkinson’s Disease Rating Scale) motor scores following adherence to a longitudinal resistance training program. Parkinson’s patients within each study were subjected to approximately seven to 12 weeks of resistance exercises, primarily targeted to postural and appendicular muscle groups. The mean UPDRS III score across all the trials examined was 31.1 with a standard deviation (SD) of 8.3. The mean post-therapy score was 25.7 with an SD of 8.6. Post-analysis paired t-test showed a statistically significant p-value of 0.00528. The T-score was –3.654, beyond the 95% region of significance of –2.2622 to 2.2622. These results reflect only the 10 papers included in this study and could present analytical bias due to low power.

Discussion: We found a significant decrease in UPDRS III scores after a longitudinal resistance training plan. These results suggest that resistance training may be a therapeutic, non-invasive, and non-pharmacological option for the treatment for Parkinson's disease. Repeated resistance training leads to the hypertrophy of muscle fibers, significantly improving muscle motor control Resistance training in the form of exercises such as bench press, rowing, leg curls, leg extensions, and deadlifts significantly decreases motor deficits that lead to tremors, rigidity, and stooped posture.

Conclusion: UPDRS III results suggest resistance interventions via bench press, leg curls, rowing, leg extensions, and deadlifts significantly reduce motor deficits that lead to Parkinsonian rigidity, postural instability, and resting tremors. Furthermore, we plan to explore if other forms of physical activity including aerobics, Tai Chi, and balance training yield similar or improved symptom relief. Resistance training may be an optimistic, non-invasive and non-pharmacological therapy for Parkinson’s neuropathology as it shows promising measures for the independence and livelihood of PD patients. Future studies should analyze the therapeutic effects of other physical therapies (aerobics, aquatic training etc.) in treating Parkinson disease.