Men and women do not have exactly the same biological rhythms. Several studies have demonstrated this: whether it is physical activity or sleep, needs differ. Women, for example, would be more sensitive to variations in their circadian cycle. Result: they would benefit more from going to bed before midnight.
Differences in sleep habits
According to a synthesis carried out by researchers from the universities of Stanford and Harvard (United States) and Southampton (United Kingdom), published in Sleep Medicine Reviewwomen would have an easier time entering the first phases of sleep – drowsiness, light sleep, then deep sleep – before reaching paradoxical sleep. They spend on average around ten minutes more there than men. Additionally, their REM sleep phase would occur up to 15 minutes earlier in the cycle, particularly after ovulation.
Result: for the same amount of time spent in bed, women sleep slightly more than men – more effective sleep, therefore.
The role of hormones in sleep
Sleep does not escape the influence of hormones. As men age, their testosterone levels decrease, which can affect the quality of their rest. For women, monthly hormonal fluctuations can disrupt the nights: insomnia, frequent waking up or light sleep are more common before and during periods. These disorders, often associated with anxiety – which is also more common in women – partly explain why more women are diagnosed with sleep disorders. Certain conditions like restless legs syndrome or sleep-related eating disorders are also more common among them. Men, for their part, are more affected by sleep apnea.
Women are more morning people than evening people
The authors of the study also indicate that the female body begins its transition to sleep earlier. The secretion of melatonin, the sleep hormone, begins on average at 10:49 p.m. in women, compared to 11:28 p.m. in men. They also tend to wake up naturally earlier.
In addition, body temperature begins to rise at 4:46 a.m. in women, while it only does so at 6:11 a.m. in men.
So many differences that make the co-author of this comparative study, Sarah L. Chellappa of the University of Southampton, advise heterosexual couples not to force themselves to go to sleep at the same time, and instead to follow their own sleep rhythm.