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04 Feb 2004

When to eat before & after exercise
Hi Doc

I would like to know what your opinion is on how long before & after an exercise session, a person should eat to still be able to lose weight/burn fat: I have been informed by one of the instructors at gym(a very good instructor) to eat at least 3hrs before and 1hr after exercise & obviously not to eat later than 2hrs before you sleep. She stated that fat-burning actually only starts after your cardio workout therefore you should wait 1hr before consuming anything as to make sure that your body uses your stored energy and not energy from food consumed just after exercising. What is your outlook on the above?
Your advice & opinion is much appreciated.
Answer 325 views

01 Jan 0001

Hi Lea

There's some truth in what the instructor has said, although a few 'urban legends' too - there is a lot of misconception about diet and exercise and when to eat.

Before exercise, it's probably best to eat at least one hour before the session - any less than this and your blood insulin levels rise, and to cut a long story short, this decreases fat use and increases carbohydrate use, so for optimal fat burning, you should eat at least one hour before training.

After exercise, my opinion is that you should eat as soon as you are able or your appetite has returned. The body will need to replace any fuel stores that have just been used, and the best way to speed up recovery would be to eat soon after exercise. As for fat burning, you must remember that the body needs to replace a certain amount of energy and nutrients, and so you can't really cheat the process by eating sooner or later. All that will happen is that you will get hungry again at odd times. So, try to eat as soon as you can and it should be fine.

Hope this helps
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