Two words: chocolate milk.

An enticing body of nutritional science suggests that you should eat or drink immediately after exercising, in order to help your muscles recover. If the foods you ingest contain both carbohydrates and protein, your muscles will refuel more fully. And if the food is low-fat chocolate milk, even better; it contains a nearly physiologically ideal ratio of carbs to protein. Experiments have shown that people who drink chocolate milk after a workout recover better, lose more body fat, and gain more muscle than subjects who have a sports drink. The caveat: If you don't exercise vigorously for at least 45 minutes, you don't need recovery chocolate. That's incentive enough to get me out on the trails a few times a week.

Brush like a stork.

Before I began my book, I would have told you I had no problem with my balance. Then, following the advice of Jay Hertel, PhD, a professor at the University of Virginia who studies wobbly people, I tested myself, standing on one leg and almost immediately headbutting the wall. Ever since, I've been training. My regimen consists of a single exercise—brushing my teeth on one leg. "It sounds silly," Hertel says, "but if you do that for two minutes a day, you're working your balance really well." Bonus: After months of watching me floss and wobble, my husband remains amused—which is good for another kind of health, that of our marriage.

Gretchen Reynolds's book The First 20 Minutes: The Myth-Busting Science That Shows How We Can Walk Farther, Run Faster, and Live Longer (Hudson Street) is out this month.

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