The importance of sleep
Scientific facts about sleep
- Long-term sleep deprivation could result in body fat gain. Even in the short term, when we sleep less and our calorie intake is restricted, researchers suspect a decrease in fat loss versus muscle loss.
- Altered sleep causes a decrease in cognitive performance.
- Sleep is the period during which the greatest secretion of growth hormones can be observed.
- There appears to be a persistent link between the number of hours of sleep and a person’s fat percentage. More accurately, fewer hours of sleep seem to be associated with a higher amount of body fat. This association persists after having checked most of the confounding variables.
- Sleep deprivation seems to increase the appetite.
- Little sleep or even too much sleep might be linked to insulin resistance in the long run! With 7 or 8 hours per night, you’re likely to get by!
- Typically, sleep is associated with testosterone levels. Although the strength of the correlation is not that great, studies have noted a relationship. So, very little sleep could be associated with lower levels.
- Sleep deprivation seems to alter the regulation of cortisol (a hormone secreted in times of stress). Normally, cortisol appears to be higher in the morning and it then decreases in the evening. With little sleep, it could remain increased throughout the day (that’s negative!)
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Impact of Five Nights of Sleep Restriction on Glucose Metabolism, Leptin and Testosterone in Young Adult Men
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