Adverse Events During a 12-month Multi-Site and Dose-Response Aerobic Exercise Intervention

Area of Science:

• Gerontology
• Exercise Physiology
• Public Health

Background:

• Older adults are a growing demographic, and physical activity is crucial for their health.
• Understanding the safety profile of exercise interventions is vital for promoting active aging.

Purpose of the Study:

• To determine the incidence of adverse events (AE) in older adults undergoing a year-long exercise program.
• To investigate the relationship between exercise intensity (dose-response) and AE frequency.
• To identify demographic factors linked to AE risk in this population.

Main Methods:

• 648 older adults were randomized into stretching/toning (S&T), 150 min/week aerobic (150Ex), or 225 min/week aerobic (225Ex) groups.
• Adverse events were systematically tracked; event rates were calculated based on adherence and study duration.
• Generalized linear models and post hoc comparisons (IRRs) were used to analyze AE incidence across groups.

Main Results:

• 306 AE were reported; 44% were intervention-related. No dose-response for all-cause AE was found.
• Intervention-related AE were more common in aerobic groups (150Ex: +77%, 225Ex: +88% vs. S&T).
• Higher adherence linked to fewer all-cause AE; greater comorbidity associated with more AE.

Conclusions:

• Aerobic exercise slightly elevates intervention-related AE risk in older adults, though overall risk is low.
• High adherence to exercise regimens is associated with reduced AE incidence.
• Exercise interventions, particularly aerobic, appear safe for older adults, with benefits likely exceeding potential risks.