Dear Reader,

Does the following scenario sound familiar? A child is being forced to sit around for an hour, putting off swimming on a hot summer day because s/he had an ice pop for a snack. Is this wait even necessary?

Well, a general rule of thumb does exist when it comes to the timing of eating and exercise. Here are the recommended wait times:

• Less than 1 hour for a snack of 200 or fewer calories
• 1 - 2 hours for a liquid meal (such as a liquid meal replacement or blended meal — a smoothie)
• 2 - 3 hours for a smaller sized meal: 200 - 400 calories
• 3 - 4 hours for a larger meal: over 500 calories

Additional details may factor into these recommendations, extending wait times further. For example, fat and fiber slow digestion. These ingredients cause food to remain in the stomach a little longer than carbohydrate foods that are low in fiber.

The timing and type of workout are other considerations that may dictate when and what a person eats. During exercise, blood is directed to working muscles, supplying oxygen and other nutrients to these tissues. This is more of an issue for high intensity activity because the stomach then may only receive 20 percent of its usual blood flow. As a result, exercising too soon after eating slows digestion. Food may remain in the stomach longer, causing discomfort and possible cramping. This can seriously impair performance if one is competing, or make a regular workout quite unpleasant. High impact aerobicizers also may not be able to tolerate a great volume of liquids just before exercise because of too much "sloshing" around in the stomach. Drinking 16 ounces of fluid two hours prior to exercise allows time for absorption and peeing of any excess. In general, when physical activity is expected to be intense, permit slightly more time for digestion and absorption.

Individual differences must be considered as well. For people who are sensitive to abrupt changes in blood sugar levels, it's recommended not to have high sugar foods or beverages 30 - 45 minutes before exercise. This is because a fast rise in blood sugar initiates a release of the hormone insulin, which quickly lowers blood sugar in these people, leaving them weak and tired. Also avoid foods or beverages containing high levels of fructose sugar in particular because they're reported to cause stomach irritation and discomfort.

As far as carbohydrates go, stick with the complex kind. Complex carbs taken two or three hours before exercise can help improve performance. Some excellent energy-sustaining choices include:

• apples, oranges, pears, bananas
• oatmeal, pasta, low-fat whole grain crackers
• skim milk, non-fat yogurt

Low-fat proteins, such as chicken and turkey, usually are tolerated well before exercise.

The message to leave with here is... experiment with foods and timing of meals during training — never just before an important competition! Oh yeah, regarding the scenario mentioned earlier... the ice pop was only around 70 calories. The child probably could have gone swimming sooner. However, with any water sports, there's a risk of cramping in the water, so one might crawl with caution.

Alice

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