By Krista Scott-Dixon |
It’s been a few months since you started working out regularly, and you’re determined to make the best of your efforts. So you’ve been chugging a big protein shake after each workout, snacking on energy bars throughout the day, and downing sports drinks during your workouts — to prevent losing any precious electrolytes, of course.
No harm in going back for seconds — you figure you’re burning it off. But are you?
In an effort to provide robust support for their new fitness routines, many enthusiasts end up taking in more concentrated fuel than their bodies can put to good use. The result: Excess calories, sugars and simple carbs — and less than optimal fitness (or weight loss) results.
What to Eat
Gels, bars, drinks and powders certainly have their place in the athletic larder. But frankly, most people need to worry a whole lot less about which of these prepacked products to choose and a whole lot more about making whole, fresh foods the center of their eating strategy.
Beyond the insulin-spiking sugars, low-quality ingredients, additives and chemicals in processed foods, all of which can cause inflammation and disease, the sheer caloric density of many of these products tends to work against our body’s mechanisms for appetite control.
Take, for example, cholecystokinin (CCK), a hormone released into your small intestine as you eat that helps you feel full. When you eat whole, natural foods, this process works as it was designed, because the body digests these types of foods more slowly, allowing the CCK to do its work. But the body digests processed foods — especially refined carbohydrates — much more quickly, and doesn’t give the CCK a chance to kick in.
But eating whole, unprocessed foods isn’t just about appetite control; it’s about nourishing your body. “Whole foods tend to be digested more easily because they’re recognized by your body as food,” says Brendan Brazier, pro triathlete and author of The Thrive Diet: The Whole Food Way to Lose Weight, Reduce Stress, and Stay Healthy for Life (Da Capo, 2007). “In the case of plant-based foods, they’re also alkaline, so they reduce the acid load on your body that training creates.” (For more on acid-alkaline balance see “The pH Factor” in the March 2007 archives.)
John Berardi, PhD, founder of Precision Nutrition, agrees: “When it comes to vitamins, minerals and phytochemicals, no pills can even come close to what good old fruits and veggies contain.” (For five foods to eat every day — and five to avoid — see “In With the Good, Out With the Bad” in the April 2007 archives.)
When to Eat
Many experts suggest that you strive to eat something light, with more carbs than fat and protein, an hour or two for fuel before your workout, so that your food is already digested and available for uptake by the time you begin exercising.
Right after training, your body needs carbohydrates and protein to rebuild muscles and decrease levels of catabolic hormones like cortisol, which break down muscle. And experts generally agree that the sooner you eat postworkout, the better, because eating within 45 minutes of exertion allows you to take advantage of the much-lauded “glycogen window” (a relatively brief postexercise period during which your body makes the best fitness-building use of available nutrients).
To replenish muscle glycogen postworkout, Berardi recommends eating small portions (about 1/2 to 1 cup) of starchy carbohydrates such as whole grains or sweet potatoes with a little lean protein. Brazier suggests easily digested fruits such as mango, papaya or banana and a handful of nuts.
If your workout lasts longer than an hour, be sure to consume 30 to 60 grams of easily digested carbohydrates per additional hour during activity, says Liz Applegate, PhD, director of sports nutrition at the University of California, Davis. That amounts to about two or three handfuls of raisins or one large banana. If you can’t tolerate whole foods during activity, experiment with sports gels (find recipes for homemade versions online or in ). “And don’t forget to rehydrate afterwards!” she adds.
How Much to Eat
Much of the hype surrounding fitness nutrition involves protein intake, but you may not need as much as you think. A 2007 study published in Applied Physiology, Nutrition, and Metabolism found that the participants — physically active males, age 20 to 22 — needed just 10 grams of protein and 21 grams of carbohydrate after exercise to achieve the desired result of elevated protein synthesis, which helps build muscle. (That’s about the equivalent of 11/2 cups of skim milk or about 3/4 cup of black beans.)
Active people do need a bit more protein than sedentary individuals, but not in the quantities we tend to consume it. According to a 2006 study published in the Journal of the International Society of Sports Nutrition, about 0.5 to 0.8 grams of protein per pound of body weight per day is enough to repair muscle. So an active 150-pound person would need 75 to 120 grams of protein daily — the equivalent of three card-deck-size pieces of meat or 2 1/2 cups of cottage cheese. For vegans, Brazier suggests a combination of hemp, leafy green vegetables, brown rice and pea proteins.
In the same way we tend to overestimate how much protein we need, we tend to underestimate how much fat we can include — especially good fats, like the ones found in nuts, seeds and avocados. Such foods increase satiation, helping you feel full longer and keeping blood-sugar levels constant. Some studies indicate diets with over half of daily calories coming from fat don’t adversely affect body fat and, in fact, can increase endurance and decrease injury rates in runners. But since fats take three to four hours to digest and enter the bloodstream, and slow the emptying of carbs and fluids from the gut, be sure not to load up on fatty foods right before a workout.
We do tend to overestimate how many calories we burn when we’re active, so keep in mind fats are more calorically dense than other foods. Caloric burn depends on several factors — age, sex, body size and workout intensity — but here are some typical examples of calories burned in a half-hour workout.
Approximate number of calories burned
If you’re exercising at a moderate pace for half an hour, five days a week, you’re probably burning 900 to 1,400 extra calories each week. But if you have a 500-calorie protein shake after every workout, you might end up with a net gain of as much as 1,600 calories (enough to trigger a half-pound weight gain) per week! It’s worth noting that if you increase your intensity with interval or sprint training, you’ll burn more calories during that same 30 minutes of exercise and also boost your postexercise caloric burn — but you might also find your appetite ramping up, making it just as important that you keep an eye on your intake and moderate any temptations to gobble down fitness junk food like it’s going out of style.
Applegate suggests that moderately active people aim for about 250 to 300 grams of carbohydrates per day. (Two cups of brown rice is about one-third of that.) About 30 percent of calories should come from good fats such as nuts, seeds, avocados and oily fish, says Berardi. Because fats are calorie dense, getting enough of them doesn’t require lots of slathering, drizzling and dunking — just regular inclusion with your whole-foods meals and snacks.
The bottom line: While your need for carbohydrates, protein and good fats does increase with activity, it’s important to balance your food intake with your activity and your body’s real requirements. As long as you’re relying primarily on whole foods, your body will do a good job of helping you regulate how much you really need.
Overindulging on processed fitness snacks — even the healthy kind — can easily lead to unintended overload. But don’t let that stop you from getting enough wholesome nourishment to fuel your body’s fitness efforts or you’ll be doing yourself a real disservice.
As Berardi points out, “When people ask what’s more important, good nutrition or exercise, it’s like saying what’s more important to life, your heart or your lungs? It’s both — they act in concert and independently. You need them both if you want to change your body substantially.”
by Liz Applegate, PhD (Kendall/Hunt, 2005) — An introductory nutrition textbook that explains key concepts and practical applications. by Brendan Brazier (Da Capo, 2007) — Sports and lifestyle nutrition from a vegan triathlete.