Objectively measured actual physical activity

Assessments of physical activity were obtained using an accelerometer that was worn on the wrist of the participants’ dominant hand. A 1 s-interval was used to capture “activity counts” of the respective participant. Activity counts were converted to average minutes spent resting, or in light (< 3 metabolic equivalents (METs)), moderate (3–6 METs), vigorous (6–9 METs), and very vigorous (> 9 METs) physical activity. Cut-offs for different intensity levels of physical activity were set according to the recommendations of Sasaki et al. [43]: light activity 0–2690 counts per minute (cpm), moderate activity 2691–6166 cpm, intensive activity 6167–9642 cpm, and very intensive activity ≥9643 cpm. The minutes spent in each level were calculated for three separate time periods over each day (morning: 6 AM − 12 noon., afternoon: 12 noon – 6 PM, and evening: 6 PM – 11 PM). For each time period a variable was built which accounted for total minutes of light, moderate, and vigorous physical activity. Additionally, the number of steps taken during each of the three time periods of the day were counted, and total daily steps were calculated.