Old 06-12-19, 10:06 AM
just another gosling
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Join Date: Feb 2007
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Originally Posted by Happy Feet View Post
Funny but I was thinking about this very thing yesterday.

My thinking is that it does not matter at all when you eat as far as fat storage goes, as long as you do not over eat, because you do not use the food you eat right away regardless. To my understanding it is:

1. Digested
2. Used to replace glycogen in muscles and liver
3. Stored as fat

That process takes time if your are eating slow release carbs or protein. You don't eat and then instantly gain usable energy from it unless you are eating fast carbs/starch/sugar.

Conventional wisdom suggests you should eat a big breakfast because you are going to be more active during the day but that energy is coming from stored glycogen, not the breakfast (unless you eat fast carbs/sugar). The morning energy comes from the replacement of glycogen that occurred the night before. This is the thinking behind carb loading the night before a big event. So, if I'm correct and that's a big "if", when you skimp on your evening meal the day before you will be climbing out of a big energy deficit the next morning unless you try to play catch up by eating fast acting carbs/sugars. I think this is why some people struggle with poor food choices during the day - the body is demanding instant energy to get out of the hole - especially if you skip breakfast as well.

If you eat in the evening your body has 8 hours to replenish glycogen before morning activity. Then it is steady small amounts to continue the replacement process during the day. The key in the evening is not to eat more than you have burned during the day.

As long as you are using your glycogen stores and don't overeat, the food digested should go first to that process, even at night. I think people blow this though when they do not exercise and overeat and blame it on the time of eating instead of the amount of calories in/out.

Those are my thoughts on it.
8 hours to replace muscle glycogen. However during the night your brain is actually very active and burning calories. It gets those calories from liver glycogen. Normally in the morning your liver is about 400 calories low on glycogen. Here's a little primer on how that all works during sleep, with a focus on fat burning: metabolism and energy use in sleep

The discussion in the link explains why it's a good idea to have protein before bed and again with breakfast. It also tells why you feel crummy without a good breakfast. Depleted liver glycogen makes me cranky. You don't have to replace the whole 400 calories all at once, but it's fine to do that. I always have 400 carb calories before a long ride day.
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