Validation of a new self-report instrument for measuring physical activity

Area of Science:

• Exercise Physiology
• Public Health
• Biostatistics

Background:

• Accurate measurement of physical activity is crucial for public health research and interventions.
• Existing methods like accelerometry and physical activity diaries have limitations in capturing diverse daily activities.

Purpose of the Study:

• To develop and validate a novel physical activity scale for assessing 24-hour activity patterns.
• The scale aims to quantify physical activity across sports, work, and leisure domains.

Main Methods:

• A physical activity scale was developed using data from 2500 Danish adults (20-60 years).
• Activities were categorized into nine MET (Metabolic Equivalent of Task) levels.
• Concurrent validity was assessed against accelerometry and physical activity diaries in 40 participants.

Main Results:

• The physical activity scale demonstrated high correlation with physical activity diaries (r = 0.74, P = 0.000).
• Correlation with accelerometer data was poor (r = 0.20, NS).
• The scale systematically overestimated MET-time compared to diary estimates, with discrepancies increasing with higher activity levels.

Conclusions:

• The developed physical activity scale is a simple and valid tool for measuring physical activity in sedentary to moderately active Danish adults.
• It effectively integrates work, leisure, and sports activities into a single measure.
• The scale is easy to administer and provides detailed insights into activity levels and total daily physical activity.