![Sample our Bioscience journals, sign in here to start your access, Latest two full volumes FREE to you for 14 days]({"type":"image" , "src" : "/sda/5925/TOC-Subject-Sample-2021-Bioscience.jpg"})
Abstract
Aim: Objective methods were used to evaluate children’s sleep and physical activity over several days in order to test the hypotheses that: (1) low average sleep duration and/or sleep efficiency are linked to a low amount of physical activity; and (2) a reduction in sleep quantity and/or sleep efficiency during the night is followed by a decrease in physical activity the following day.
Methods: This is a multi-centre, observational study involving 276 children, aged 10.5–12 years, from diverse urban settings in Croatia, Slovenia and the US. Sleep and activity were monitored for 2–6 days (median = 4) using the Sensewear Armband™ multi-sensor body monitor.
Results: While average sleep duration and efficiency were unrelated to physical activity, within-subjects associations revealed that an extra hour spent in bed during the night was followed by a 16-minute decrease in moderate-to-vigorous physical activity (p < 0.001). This was accompanied by a 4.5 kJ/kg and 5.9 kJ/kg lower total daily energy expenditure in boys and girls, respectively (p < 0.001).
Conclusions: This study found no evidence for a link between short sleep and low or reduced physical activity.
Acknowledgements
We would like to thank all the children and their parents for the time and effort they devoted to this study.
Declaration of interest
This work was supported by the Research Fund of the Ministry of Science, Education and Sports of the Republic of Croatia, grant number 034-0342282-2325. The authors report no conflicts of interest.