Heart-Guided exercise may keep aging bodies stronger

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Age 65 to 85 years, community-dwelling * Able to walk independently, without assistance * Able to understand study procedures in Mandarin or Taiwanese and voluntarily provide informed consent * Willing to undergo health examinations and testing, and to provide historical health examination records * Completed a health status questionnaire covering medical history, medication use, and comorbidities * Physical Activity Readiness Questionnaire Plus (PAR-Q+) results indicating suitability for exercise training (or written physician clearance obtained if any positive response) * Completed the International Physical Activity Questionnaire (IPAQ), with results not meeting the criterion for regular exercise within the past 6 months (i.e., fewer than 2 sessions/week or less than 30 minutes/session of moderate-intensity aerobic exercise) Exclusion Criteria: * Cognitive impairment or dementia precluding understanding of study procedures or compliance with test instructions * Lower-extremity fracture, joint surgery, or joint replacement within the past 3 months precluding safe completion of sit-to-stand or walking tasks * Severe joint pain precluding safe completion of baseline test movements, as assessed by study personnel * Unexplained syncope or fall history within the past 3 months, or safety concerns as assessed by study personnel * Acute illness (e.g., fever, acute infection) * Cardiac pacemaker or incompatible metal implants affecting bioelectrical impedance analysis (BIA) measurement safety * Meeting the criterion for regular exercise within the past 6 months per the International Physical Activity Questionnaire (IPAQ) (≥2 sessions/week, ≥30 minutes/session of moderate-intensity aerobic exercise) * Physical Activity Readiness Questionnaire Plus (PAR-Q+) screening results indicating unsuitability for exercise training, without written physician clearance * Unstable cardiovascular disease, including unstable angina, uncontrolled atrial or ventricular arrhythmia, uncontrolled resting sinus tachycardia (\>120 beats/min), decompensated congestive heart failure, third-degree atrioventricular block without a pacemaker, acute pericarditis or myocarditis, or recent thrombosis/thrombophlebitis * Uncontrolled diabetes (HbA1c \> 9%, resting blood glucose \> 300 mg/dL, or \> 250 mg/dL with ketosis) or poorly controlled hypertension (systolic blood pressure \> 180 mmHg or diastolic blood pressure \> 100 mmHg) * Use of medications that may interfere with muscle metabolism (e.g., high-dose corticosteroids, immunosuppressants) * Symptomatic orthostatic hypotension (blood pressure drop \> 20 mmHg) * Resting ST-segment depression \> 2 mm * Severe neurological or musculoskeletal disease precluding safe performance of study procedures, as assessed by study personnel * Currently participating in another clinical trial involving an exercise intervention * Severe anemia, acute infectious disease, or other physiological conditions deemed unsuitable for exercise training by the investigator