A research group from the University of Tsukuba focused on female athletes and clarified the effects of differences in daily training habits and reproductive function (whether or not they menstruate, and their menstrual cycle) on energy consumption during sleep and sleep stages.
Sleep plays an important role in maintaining human life, including recovering from fatigue and improving immune function. In particular, the deep stage of slow wave sleep (SWS) consumes the least amount of energy and is associated with the secretion of many hormones. It is also known that the duration of SWS can be extended by regular exercise.
On the other hand, it has been reported that energy expenditure during sleep may also differ depending on the menstrual cycle. Female athletes in sports where weight and performance are related may maintain a low body weight for a long period of time, and a high proportion of them suffer from menstrual irregularities or amenorrhea. Therefore, we investigated how factors such as the presence or absence of daily training habits, menstruation, and menstrual cycle affect energy expenditure during sleep and SWS in female athletes by comparing them with general healthy women.
The results suggest that daily training habits may affect how SWS manifests, causing differences in fluctuations in energy consumption during sleep. Furthermore, it was found that only in athletes with daily training habits was SWS energy consumption and sleep metabolism higher in the luteal phase than in the follicular phase. In this way, the researchers found that differences in women's daily training habits and menstrual function (presence or absence, cycle) lead to differences in energy consumption during sleep and fluctuation patterns of sleep stages, and that these phenomena may be related to SWS.
It is hoped that elucidating the mechanisms behind these differences will lead to the development of preventive and response measures for menstrual abnormalities in female athletes.
Paper information:[iScience] Energy expenditure and slow-wave sleep in runners: Focusing on reproductive function, chronic training, and sex