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How important is sleep for fat loss? (thread)
Miss out on sleep and you'll be have no energy, meaning you may skip the gym, go for fewer walks and generally move less. This is going to mean the "calories out" part of the in-out equation is reduced, and it will be harder to get into a calorie deficit.
When you're sleep deprived, you make poor decisions. This includes those relating to your diet. Simply put, you're far more likely to cave in to temptation and ruin the day/week's work. This seems to happen most often in the evening between dinner and bed.
Sleep is when you recover. If you're sleep deprived you're far more likely to be under-recovered from your training. This will lead to adherence problems and poor training - resulting in fewer calories expended.
You'll also have hormone problems from lack of sleep (particularly testosterone which is crucial for building and maintaining muscle) which can lead to all sorts of problems.
