Defining Continuous Walking Events in Free-Living Environments: Mind the Gap

Area of Science:

• Physical Activity Epidemiology
• Biomedical Engineering
• Public Health

Background:

• Defining continuous walking events is challenging in free-living conditions due to interruptions.
• Existing methods for defining walking events often overlook the impact of interruptions on physical activity intensity.
• Accurately quantifying continuous physical activity is essential for understanding its health benefits.

Purpose of the Study:

• To develop and validate a novel methodological approach for defining continuous walking events.
• To incorporate the influence of short interruptions and intensity variations into the definition of walking events.
• To explore the impact of different walking cadence thresholds on the measurement of moderate-to-vigorous physical activity (MVPA).

Main Methods:

• Recruited 24 university staff members for a 7-day continuous accelerometer monitoring (activPAL™) and activity diary study.
• Developed a novel method to combine short interruptions between walking bouts based on average walking cadence.
• Defined moderate-to-vigorous physical activity (MVPA) using minimum cadences of 76, 100, or 109 steps/min.

Main Results:

• The novel method, accounting for interruptions, significantly increased the calculated daily time spent in MVPA across all tested cadence thresholds (p < 0.001).
• For the 76 steps/min threshold, average daily MVPA increased from 75.2 to 86.5 minutes.
• Statistically significant increases in MVPA were observed for 100 steps/min and 109 steps/min thresholds as well.

Conclusions:

• A new methodological approach effectively defines continuous walking events by integrating interruption data and intensity.
• This method enhances the accuracy of measuring physical activity, particularly MVPA, in free-living settings.
• This approach will facilitate future research on the relationship between continuous walking and health outcomes.