It's hot outside and I want to exercise after dinner, when it is a little cooler. Typically, I jog for a couple of miles or play one hour of tennis or basketball. I'm wondering how long I should wait after dinner to start these exercises. I did quite some search and the answers are all over the map, from no waiting at all to 3-4 hours. Can someone please give me some definitive and reliable hints, especially supported by research studies? Or there is no trivial answer because it depends on so many factors such as the amount of food taken in dinner and the intensity of exercise?
As baldy mentioned, this really comes down to what you feel comfortable with. If you feel fine exercising with food in your stomach, then exercise right after dinner if that works best for you, as you will enjoy the same benefits. The reality is, however, that most people aren't able to exercise at full capacity right after eating. The guidelines the Mayo Clinic sets are
Large meals. Eat these at least three to four hours before exercising. Small meals. Eat these two to three hours before exercising. Small snacks. Eat these an hour before exercising.
They list the sluggishness caused by eating as the primary reason for this wait.
If you have reasons to worry about heart disease, research studies show that exercising soon after a heavy dinner is best, as it helps to clear your arteries. Depending on the reason for your exercise, this may weigh more heavily on which time you choose.
In summary, if you're exercising to improve in a particular area, you should wait until whatever time you are capable of performing your exercise at full capacity. If you are exercising for general fitness, then exercise whenever works best, with a preference for soon after the workout if you ate a large, fatty meal. As always, the most important thing is that you are exercising, and the time you choose to do so is a secondary issue.
In my opinion this would be a personal preference, based on the amount of food consumed, and any discomfort experienced while running. Seeing that you actually eat while running when doing long endurance events, your body is adapted to exercise with food in your stomach.
I would add some warnings - you may avoid very strenuous cardio or abs workout just after you have had a big meal. Though it may not do any harm as such, but it may interfere with digestion or make you feel queasy.