Reader Question and Answer

By Bryan Haycock, Editor-in-Chief
Originally posted 12/26/01 in the Think Muscle Newsletter

Discuss this article in the HST Forum

Question:
I am confused about what I should eat before and/or after I exercise. Some people day don't eat anything before, other people say don't eat anything after. How do I decide?

-K

Answer:
A pre-workout meal can help to ward off hunger and provide energy and nutrients to working muscles while blood flow to those muscles is greatest. The right kind of pre-workout meal may actually increase muscle-building hormones needed by your body for fast recovery.

To curb appetite, eat a small nutritionally complete meal containing carbohydrates and protein about 60 to 90 minutes before you exercise. A mixed meal containing both protein and carbohydrates will prolong digestion. This helps to curb appetite longer. Try to avoid high fat meals right before training though. High fat meals eaten before exercise can blunt, or prevent, the natural increase in growth hormone levels caused by exercise.

Exercise creates and temporary window of opportunity when nutrient uptake into muscles is easiest for the body. To take advantage of this window of opportunity, drink a meal replacement drink about 30 minutes prior to, or immediately after, your workout. As a liquid meal, it will digest quickly allowing glucose and amino acids to be plentiful in the blood stream when nutrient uptake is highest in your muscles. A good carb/protein drink will ensure optimal recovery and positive results.

There may even be some benefit from drinking a meal replacement (diluted) during exercise. Drinking a meal replacement during exercise causes the levels of cortisol (a catabolic hormone) to stay lower, while insulin and GH (anabolic hormones) stay higher. Over time this may lead to faster progress in the gym.

Don't forget fluid replacement! Drink at least 8 oz of water or other sports drink 15-20 minutes before strength exercise. Then continue to drink in moderation, yet frequently, throughout your workout.

For optimum fat loss, do not eat within 2 hours before your aerobic exercise sessions. Post workout meal recommendations remain the same as above.

Question:
I have always gotten blisters on my feet from running. I have tried different socks, taped my feet, powder, Vaseline. I read in a runner's magazine about something called "tannic acid". Have you heard of this? If so, how would a person use this to prevent blisters?

-Rick

Answer:
First, let me explain a little bit about blisters. Prevention of blisters requires that you control two things, friction and moisture. There are simple techniques to deal with both problems.

The first line of defense against blisters is wearing properly fitting shoes. New shoes should be thoroughly "broken in" before wearing them in a race or during training.

Friction can be dealt with by placing a barrier at the contact point between the skin and the lining of the shoe. This can be done with athletic tape. Using "sport socks" designed to prevent blisters is also effective. If you don't have access to special socks, simply doubling them up with a thin tight pair underneath often works. Finally, the use of petroleum jelly can work by reducing friction.

Moisture can be dealt with by using talcum powder. As you mentioned in your question, an astringent may also work for some people. Astringents work by dehydrating the skin where it is applied. Astringents may also block the openings of the sweat glands though the exact mechanism is not completely understood. Without normal hydration, less fluid is available to form the blister. Eventually, the chronic use of astringents can cause the skin to develop a tuff epidermal layer that is more resistant to blistering.

Tannic acid is an example of an astringent, as are various aluminum salts commonly found in antiperspirants. An astringent product called Drysol is often recommended by professional trainers and contains 20% aluminum chloride. The best way to use a product like Drysol, or other astringent, is to apply the astringent to the feet and allow to air dry before running. Then liberally apply a powder such as talcum, alum, or boric acid to the skin, socks and inside of the shoes. After running, thoroughly wash and dry the feet (hair dryer works well for rapid drying). Then follow the same procedure as before you ran. An astringent is applied to the skin followed by an absorbent powder. Be sure to powder and change into fresh socks and preferably different shoes. You should follow this procedure every day at least once regardless of whether you run or not.

One final note, remember that blister formation is a reaction to an unaccustomed stress to the skin. If you run too infrequently you are more likely to get blisters because the running isn't frequent enough to cause callus formation at the point of contact. For this reason it is important to use a periodized strategy to increase your running volume over time using frequent running sessions.

Question:
I've just had a baby and was wondering how my diet will effect breast feeding. I worked out before and throughout my pregnancy and feel that I ate pretty well. I've always taken a protein powder but I was wondering if my protein requirements go up while I'm breast feeding. Don't I lose protein in the milk? Will my protein drink effect the nutrient composition of the milk? Any help would be greatly appreciated.

Thanks,
Sarah

Answer:
While nursing it is important to consider both your protein and calorie needs. If calories are inadequate it may inadvertently increase protein needs. This is especially important for nursing women who exercise regularly.

Energy needs for an exclusively breastfeeding (no formula) woman are approximately 670 additional calories per day. Taking into consideration gradual weight loss, the average increase needed is about 500 calories per day. In women who are not unusually thin (unusually thin = <10-12% body fat during pregnancy), a moderately negative energy balance is not likely to affect milk quality or volume.

The recommended increase in protein intake during lactation is estimated to be about 20 g/day. This recommendation is based on information from "nitrogen balance" studies in lactating women. Low protein intakes are unlikely to affect milk volume but may alter the amino acid profile of breast milk. A chicken breast or other lean meat in an equal-size portion would provide about 20 grams of protein. Protein powders are also very useful for adding protein to the diet because of their convenience and high nutritional value. Generally protein powders provide 20 grams of protein per serving. You can use a protein drink anytime to meet this need, with a meal, in the morning, before bed, or even when the baby wakes up in the middle of the night to be fed, just as long as you get 20 additional grams per day.