Figure 5
Mean heart period (RRmean) and heart rate variability indices of 8 cleaning workers during a workday. a) RRmean, b) ln(LF/HF), c) ln(TP) and d) ln(HFP) derived from 5 min recordings sampled every 30 min. Measurements are categorized according to work period (9:00 - 13:00), break during work (11:00), leisure period (13:30 - 22:00) and sleep periods (22:30 - 04:30). Error bars indicate standard error of the mean.