I stumbled upon a study done in 2010 in the University of Chicago. 10 overweight individuals (7 men and 3 women) were fed a 10-percent below maintenance level calorie-restricted diet for 14 days. They slept either 5.5 hours or 8.5 hours on average.
What happened was after these 14 days those who slept only 5.5 hours suffered a decrease in fat loss of 55 percent and also an increase of lean muscle mass loss of 60 percent. This leads to a lowered metabolism speed by lowering the Basal Metabolic Rate (BMR).
This proves that if you are on a calorie-restricted diet (dieting, like when trying to lose fat or lean down for a contest), sleep deprivation is your enemy – you start holding onto your fat AND in the same time giving up your muscle.
The take-away message is: If you want to avoid getting stuck in your fat loss efforts you must (among other things) avoid sleep deprivation. 5.5 hours sleep a day is all you need to put you in this unfavorable state! Keep losing fat AND keep your muscle too by making sure you sleep at least 8-8.5 hours a day. That’s all you need… as far as sleep goes.
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But what happens if you over sleep? For instance on saturday, one of my day off, im so exhausted from the week that i had, that if i dont set my alarm for 8 hours i will sleep for 12 hours, resulting in less meals for the day. Is there a negative effect on over sleeping?
Thanks.
As far as I know both under- and oversleeping are not good. The optimal sleep time is 7-8 hours but more than 8h is not beneficial to you. Keep in mind that there is a (very) small number of individuals who require a lot less sleep to function as well as those who need 7-8h. Those individuals usually require 4-5 hours and they do much better than when they sleep 7-8h. Most likely, you and I are not in this group, but if you are you’d know it already.
Thanks Ivan i will have this in mind..