Therapeutic potential of respiratory phase-coupled exercise for preventing dopaminergic decline in early stage Parkinson's: a scoping review of neuroimaging and clinical evidence

Yilong Jiang^*

• Beijing Geriatric Hospital, Beijing, China

Background: Parkinson's disease (PD) involves an early disruption of dopaminergic systems with implications in diverse motor control systems including the respiratory one. Emerging evidence suggests that respiration–motor coupling and respiratory phase coordination with movement may engage brainstem and basal ganglia circuits relevant to the etiopathology of PD and can be target for therapeutic strategies, yet this literature remains fragmented across disciplines. Aim: To map and synthesize the available evidence linking respiratory–motor interactions with the modulation of dopaminergic mechanisms in early-stage PD, and the potential modulation of respiratory phase-coupled exercise. Methods: This scoping review included pre-clinical and clinical studies examining respiratory control, respiratory–motor–neural interactions, or reporting dopaminergic, brainstem, or clinically relevant outcomes in PD models. PubMed/MEDLINE databases were searched to identify relevant studies published prior to 21 January 2026. The review followed the Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) checklist. Consistent, risk-of-bias assessment was used to contextualize, rather than exclude, evidence and to inform identification of translational research gaps. Data were charted on study design, model, respiratory paradigm, neural mechanisms, and outcomes. Results: Thirty studies were included for the qualitative synthesis. Evidences clustered around (i) dopaminergic modulation of respiratory rhythm, (ii) brainstem–basal ganglia respiratory interactions, (iii) respiratory–motor coordination disturbances in PD, and (iv) indirect implications for respiration-coupled exercise. Evidence supports a robust mechanistic link between dopaminergic systems in sub-cortical brain areas and respiratory control centers at the brainstem which participate in the disruption of respiratory–motor coordination seen in PD. However, there is a fragmented literature across respiratory physiology, neurobiology, and rehabilitation research which rarely integrate within exercise framework. Conclusion: No study directly tested respiratory phase-coupled exercise in PD, however, converging mechanistic evidence supports a potential for exercise-target respiratory entrainment dopaminergic modulation. This scoping review identifies critical gaps and provides a physiological framework for future intervention studies.