Sleep is a vital part of recovery from any workout. Levels of various body hormones vary between night and day, and your body primarily uses light, blue light, to know that it is day. Disrupting this rhythm can have negative consequences, as seen in people who work night shifts who have worse health and mental performance.
Lack of sleep reduces your body’s energy expenditure, makes you hungrier and causes your weight loss from a caloric deficit to come from more muscle loss than fat loss. Sleeping more, on the other hand, has been shown to improve reaction time, reduce fatigue and improve sports performance, even if you are not feeling tired at prior sleep levels!
Individual needs vary, and you will know how much you need by seeing how much you sleep without an alarm clock, but as a rule of thumb, 8 hours is a good amount for younger individuals while around 7 hours is sufficient for older individuals.
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