Physical Activity in Community-Dwelling Older Adults: Which Real-World Accelerometry Measures Are Robust? A...

Area of Science:

• Gerontology and Rehabilitation Science
• Biomedical Engineering and Wearable Technology
• Physical Activity and Health Research

Background:

• Accelerometry is crucial for measuring real-world physical activity (PA) in older adults, offering clinical relevance despite inherent challenges.
• This review critically appraises the reliability and validity of accelerometry-derived PA metrics in older adults under free-living conditions.

Approach:

• A systematic literature search across eight electronic databases identified 13 relevant manuscripts for analysis.
• Data extraction focused on various reliability metrics (inter-rater, relative, absolute, responsiveness) and validity measures (criterion, construct).

Key Points:

• Established inter-rater reliability (ICC 0.78–0.99) and criterion validity (0.83–0.98) for walking, lying, sitting, and standing durations.
• Criterion validity for step count is established (0.83–0.98), with construct validity for moderate-to-vigorous PA at r=0.68–0.72.
• Relative reliability for step counts (0.24–0.82) and active calories (0.48–0.86) showed variability.

Conclusions:

• Clinicians and researchers can utilize established accelerometry measures for PA in older adults with moderate confidence.
• Further research is essential to enhance understanding of PA intensity, postural transitions, and refine measurement properties for comprehensive assessment.