Aquatic High-Intensity Interval Training for Parkinson's Disease

The Effect of Aquatic High-Intensity Interval Training on Balance, Physical Function, and Sarcopenia in Patients With Parkinson's Disease: A Randomized Controlled Trial Protocol

This randomized, single-center, parallel-group superiority trial will evaluate the effect of an 8-week aquatic High-Intensity Interval Training (HIIT) program on balance, physical function, and sarcopenia-related outcomes in individuals with Parkinson's disease (PD). The intervention aims to deliver Tabata-style aquatic HIIT (3 sessions/week) in a therapeutic pool to determine adherence and preliminary efficacy compared with standard care (no structured exercise program).

Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by motor and non-motor symptoms that impair quality of life. Pharmacological treatments alleviate motor symptoms but leave residual motor and non-motor complications and carry long-term adverse effects. Non-pharmacological therapies-particularly exercise-improve motor and non-motor outcomes via mechanisms such as enhanced dopamine release, corticostriatal plasticity, and increased BDNF after vigorous exercise. HIIT (including Tabata protocols) has emerging evidence for benefit in PD but land-based HIIT can be limited by balance deficits and fall risk. Aquatic HIIT may provide a safer environment (buoyancy, reduced joint load, natural resistance) and improve adherence.

This single-center trial will recruit 56 participants (aged 55-75) with PD (Hoehn & Yahr stages 2-3) and balance difficulty to be randomized 1:1 to aquatic HIIT (n=28) or control (standard care; n=28). The intervention comprises 8 weeks of supervised Tabata-format aquatic sessions (20s high intensity/10s rest ×8 cycles per set; warm-up and cool-down included) three times weekly. Primary endpoints include changes in Berg Balance Scale (BBS), Short Physical Performance Battery (SPPB), skeletal muscle mass by BIA, and handgrip strength from baseline to Week 8 (primary endpoint), with safety follow-up to Week 12. Secondary endpoints include PDQ-39, PSQI, adherence, and adverse events monitored with CTCAE criteria.

Inclusion Criteria:

• PD stages 2-3 based on Hoehn and Yahr classification system
• Balance difficulty (BBS score <45)
• Reduced motor function
• Sarcopenia (per EWGSOP2 criteria)
• Age ≥ 55
• Permission from their doctors to participate
• Absence of a history of myocardial infarction within the past 3 months
• Capacity to provide informed consent to participate in the study

Exclusion Criteria:

• Cardiac instability (angina, decompensated congestive heart failure, severe arteriovenous stenosis, uncontrolled arrhythmias, etc.)
• Active infection or acute medical illness
• Hemodynamic instability
• Labile glycemic control
• Inability to exercise (e.g. lower extremity amputation with no prosthesis)
• Severe musculoskeletal pain at rest or with minimal activity
• Inability to sit, stand or walk unassisted (walking device such as cane or walker allowed)
• Shortness of breath at rest or with activities of daily living