Accelerometer data processing
Data were processed using ActiLife5 software. The produced report contained daily information about wear time, number of steps, METs, and time spent doing activities of different intensity levels. Daily data was only valid if the accelerometer wear time had been at least 600 min for that day. If wear time for a certain day was less, or the accelerometer was not worn at all, imputation technique was applied, replacing invalid day data with the previous valid day.Actigraph counts were sampled over 60-s periods (epochs). Per-epoch activity intensity was coded using integrated Freedson adult cut-point ranges (specifically, sedentary = 0–99 counts, light = 100–1951 counts, moderate = 1952–5724 counts, vigorous = 5725–9498 counts, and very vigorous activity > 9498 counts). To obtain weekly time spent doing a given activity, 7-day data were summarised.METs for each day were obtained using the integrated Swartz Adult Overground & Lifestyle MET rate algorithm. Daily minutes when the accelerometer was not worn (1440 min – wear time) were rated at 1 MET. Daily MET-min was calculated as [METs x wear time + (1440 min—wear time)]. To obtain weekly energy expenditure (MET-min/week), 7-day data were summarised.