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Old 08-15-2012, 12:18 AM   #4 (permalink)
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Join Date: Jan 2010
Location: Riverside, CA
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Originally Posted by SpiritOfThings88 View Post
OK, here is a question that I've always meant to research, but never have.
If you exercise (swimming, in my case) shortly after your eat (say 10 minutes), is it a waste of time? I'm not worried about getting cramps, but I've heard for years (and it may be a wives tale) that you're really not burning calories if you don't wait for an hour or so after eating.

Would love to hear some feedback on that topic. Thanks.
Sometimes there can be a competion between your digestive track and you muscles for oxygen and glycogen immediately after a meal. My experience, backed up by a cool stable isotope experiement, is that when I run immediately after eating a light meal, digestion slows down as you body focuses on getting O2 to your muscles.

But if I eat a heavier meal first, all the blood rushes to my tummy . Leaving me with less O2 and glycogen going to the working muscles. This is pretty common for me during skiing and Mt biking. If I stop and have big lunch, I just don't have much energy in my legs for an hour or so. After that I am good to go.
5'4" 55yr

2.5 years, 45 pounds later... 128ish pounds
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