It's all in the timing

American Running Association
September 19, 2005

You wouldn't take your car on a road trip with an empty tank of gas; nor should you take your body to the gym without fuel.

Distance runners who want to tone up, increase power and explosiveness, or alleviate impact force on joints are encouraged to weight train, usually in higher repetitions with lower weights than their strictly body-building friends. What are the optimal nutrients to keep things running smoothly, then, and how does when you eat them influence your results?

Fuel up before your workout

For starters, don't go to the gym famished. While consuming a three course meal 10 minutes before weight training is clearly not advisable, eating a protein and carbohydrate snack will provide fuel for a stronger workout.

As you begin to digest the protein into amino acids, your muscles will appreciate and put to work these protein building blocks as you weight train and afterward.

And as every marathoner knows, consuming carbohydrate will increase your glycogen stores. This is important for endurance events, but also in high-repetition weight training that relies on breaking down sugars for fuel. Nancy Clark, M.S., R.D., recommends a fruit yogurt or a small bowl of Cheerios and skim milk for a pre-exercise snack.

Refuel post-workout

After a hard gym (or track) workout, your muscles are in what can be termed a state of breakdown: their glycogen stores are reduced; cortisol and other hormones that break down muscle are high; the muscle damage that occurred during exercise causes inflammation; the amino acid glutamine that provides fuel for the immune system is diminished.

It's important to feed your muscles a carb-protein combination as soon as you can tolerate it. If you just drink water after your workout and dash to work, you'll miss the 45-minute post-exercise window of opportunity to optimally nourish, repair and build muscles.

In a 12-week training study, the elderly subjects who took a supplement composed of 10 g protein, 7 g carbohydrate and 3 g fat immediately after each exercise session achieved an eight-percent increase in muscle size and a 15-percent increase in strength, as compared to the control group who took the supplement two hours later -- they saw no change in muscle size or strength.

Optimal protein intake

In addition to replenishing glycogen stores, the carbohydrate is important in this first refueling session as it also stimulates the release of insulin, a hormone that helps build muscles. The protein in combination with this will repair muscle tissue and reduce cortisol. But how much protein should you eat to build muscles?

The recommended protein intake for sedentary people is about 0.45 g per pound of body weight daily. Runners should aim for 0.6 to 0.7 g. Unless you're on a restricted eating regimen such as a vegan diet, this is not hard to achieve -- most carnivores don't need to go looking for protein. Look instead for less fatty meats like chicken breast (see right).

For example, a 150-pound runner aiming for 0.7 g of protein per pound of body weight would need to find 105 g of protein in his/her daily diet. Two three-ounce servings of boneless, skinless chicken breast -- i.e., two chicken breast halves -- total around 54 g of protein, depending on how close each cutlet is to three ounces and the type of chicken.

A cup of chick peas (which are great on salads) has 12 g. Two cups of skim milk will give you 20 g. Add two hard-boiled eggs and a serving of whole cashews -- about one handful -- for another 17 g, and you've met your protein needs for the day. Alternately, three servings of chicken breast, the cashews, plus two cups of low-fat milk daily yields the equivalent protein.

Tofu is a versatile food and can be substituted for meat in most recipes, though to get the same amount of protein you will need to consume more. Chicken breast contains about four times the protein found in tofu. A three-ounce serving contains 6.4 g, the equivalent of one hard-boiled egg. (A good rule of thumb with boneless chicken is that approximately one-third of the total weight equals the amount of protein it contains. A three-ounce serving weighs 86 g and delivers approximately 27 g of protein.)

As always, but certainly in periods of heavy training, it's important to rely on overall eating habits and not merely pre-exercise loading to keep muscle glycogen high and protein available during workouts. By keeping several small meals balanced with carbs, protein and healthy fats throughout the day, you will optimize weight training and running performance.

(USDA Nutrient Data Laboratory, www.nal.usda.gov/fnic/foodcomp; J. Physiol., 2001, Vol. 535 (Pt 1), pp. 301-311; The Athlete's Kitchen, Nancy Clark, MS, RD, July 2005; www.metric-conversions.org/weight/grams-to-ounces.htm)

American Running Association, empowering adults to get America's youth moving. For more information or to join ARA, please visit www.americanrunning.org.


Article Tools
 Print this article 
 Email to a friend





Copyright © 2005 Active Network