Aquatic High-Intensity Interval Training for Parkinson's Disease

Evaluating the effect of aquatic HIIT on balance using the Berg Balance Scale (BBS), a 14-item performance-based tool assessing static and dynamic balance through functional tasks like sitting to standing, reaching forward, and turning 360 degrees. Items are scored on a 5-point ordinal scale (0-4) based on ability and time to complete, with a total score ranging from 0 (worst) to 56 (best); scores of 0-20 indicate wheelchair-bound, 21-40 indicate walking with assistance, and 41-56 indicate independent. In PD, scores <45 suggest high fall risk, and the BBS has excellent intra-rater reliability (ICC=0.98), inter-rater reliability (ICC=0.97), and criterion validity, correlating with other PD-specific measures like UPDRS.

Evaluating the effect of aquatic HIIT on physical function using the Short Physical Performance Battery (SPPB), a composite test including three subcomponents: balance (holding side-by-side, semi-tandem, and tandem stands for up to 10 seconds each, scored 0-4), gait speed (timed 4-meter walk at usual pace, scored 0-4 based on time quartiles), and chair stand (time to complete five rises from a chair without arms, scored 0-4). Total score ranges from 0 (worst) to 12 (best), with scores <10 indicating high risk for mobility limitations and falls in older adults, including PD patients. The SPPB demonstrates high test-retest reliability (ICC=0.92), intra-rater reliability, and validity in predicting functional decline and executive function associations in PD.

Evaluating the effect of aquatic HIIT on sarcopenia-related muscle mass using Bioelectrical Impedance Analysis (BIA), a non-invasive technique that estimates body composition by measuring resistance and reactance to a low-level electrical current, calculating skeletal muscle mass (ASM) and phase angle (PhA). ASM is indexed to height squared (ASM/height² in kg/m²), with sarcopenia diagnosed per EWGSOP2 criteria (<7.0 kg/m² for men, <5.5 kg/m² for women); PhA cut-offs for sarcopenia are ≤4.05° (92.9% sensitivity, 53.8% specificity) for men and ≤3.75° (78.9% sensitivity, 51.1% specificity) for women. In PD, BIA is reliable for detecting sarcopenia (prevalence 40-55%) with high correlation to dual-energy X-ray absorptiometry (DXA) as gold standard (r=0.85-0.90 for ASM), predictive validity (adjOR=0.147 for PhA), and good test-retest reliability (ICC=0.88-0.95), though wide diagnostic variations exist across criteria.

Evaluating the effect of aquatic HIIT on muscle strength using a Handgrip Dynamometer, a handheld device that quantifies isometric grip force in kilograms or pounds during maximal voluntary contraction (typically 3 trials per hand, with the highest or average value used). Measurements are taken in a standardized seated position with the elbow flexed at 90 degrees; normative values decline with age, and low grip strength (<27 kg men, <16 kg women) is a sarcopenia criterion in PD. The dynamometer shows fair to excellent test-retest reliability (ICC=0.95-0.98) and intra-rater reliability in PD, with good validity for overall strength assessment.

Evaluating improvements in quality of life using the Parkinson's Disease Questionnaire-39 (PDQ-39), a disease-specific 39-item self-report instrument covering eight domains (mobility, activities of daily living, emotional well-being, stigma, social support, cognitions, communication, bodily discomfort). Items are rated on a 5-point Likert scale (0=never to 4=always), with domain scores transformed to 0-100 (higher indicating worse quality of life) and a summary index as the mean. The PDQ-39 has strong convergent validity (correlates with EQ-5D), discriminant validity, internal consistency (Cronbach's alpha=0.51-0.96), and test-retest reliability (0.56-0.90 per domain) in PD.

Evaluating changes in sleep quality using the Pittsburgh Sleep Quality Index (PSQI), a 19-item self-report questionnaire (plus 5 roommate-rated items) assessing seven components (subjective quality, latency, duration, efficiency, disturbances, medication use, daytime dysfunction) over the past month. Global score sums to 0-21 (higher=worse sleep), with >5 indicating poor quality (prevalence ~85% in PD). The PSQI has good internal consistency (Cronbach's alpha=0.83), test-retest reliability (0.85), and validity in PD, correlating with PSG and other scales like PDSS.

Determining adherence to the intervention using attendance logs, which record session participation as a percentage (number of attended sessions / total planned sessions; Adherence defined as attending ≥80% of sessions (≤20% missed)."). Logs also note reasons for non-attendance, providing qualitative insights. This method is reliable for monitoring exercise adherence in PD trials, with group rates often >80% in supervised programs, though individual accuracy requires caution.

Monitoring and reporting adverse events using the Common Terminology Criteria for Adverse Events (CTCAE v5.0 or later), a standardized system categorizing events by organ system and severity grades (1=mild, 2=moderate, 3=severe, 4=life-threatening, 5=death-related). Events are defined as any unfavorable sign, symptom, or disease temporally associated with the intervention; serious events (grades 3-5) prompt reporting to DSMB. CTCAE ensures consistent AE reporting in clinical trials, with updates like v6.0 in 2025.