Good News for Muscles

Tuesday, September 23, 2008 - 10:29am

By Donna Feldman, MS, RD

Is there anyone who doesn’t want more muscle? From weekend warriors to professional athletes, the quest for 6-pack abs and high def biceps is never-ending. Steroids are a risky way to build muscle bulk, as many athletes discover. Muscles can’t just bulge out overnight.

The muscle-building process is relatively simple: Muscles grow in response to use. The building blocks of muscles are amino acids, found in all protein foods. Exercise + amino acids should equal muscle growth. There are plenty of food supplement products that promise to enhance muscle development, or speed muscle recovery after a workout. Are these necessary?

Milk Anyone?

One of the more surprising findings recently is that good ol’ milk may be one of the best muscle-building foods around. In a recent study, young men did resistance training 5 days/week. Three different post-workout drinks were compared for effect on muscle mass: skim milk, fat-free soy milk, and a carbohydrate drink with the same calories. While the training regimen caused all the men to increase muscle, the milk drinkers gained significantly more muscle.1 Fat-free milk is full of protein: An 8 oz cup has over 8 grams. Muscle mass requires protein. Interestingly, the milk proteins appear to be more effective than soy protein.2

Chocolate Milk?

But do muscles require chocolate? Some sports nutritionists swear by chocolate milk, and a small study of cyclists compared chocolate milk to fluid replacement or carbohydrate-replacement drinks. The chocolate milk drinkers had greater endurance.3 But cycling and resistance training are quite different activities. Cycling burns more calories than resistance training, so the chocolate was providing calories, while the milk part was providing protein. Sadly for chocolate lovers, chocolate alone is not likely to affect muscle growth.

Resistance Training Is Critical

All of these studies have one thing in common—exercise. The American College of Sports Medicine recently updated exercise guidelines issued in 1995. The 2007 version includes specific recommendations for muscle-strengthening resistance training.4 Muscle strength train is recognized as contributing to general health and fitness, as much as aerobic activities. A minimum of 2 times/week for strength training is recommended, along with at least 30 minutes of intense cardio activities 5 days/week. The ACSM website has many tips on activities and advice for novices who are just getting started.

More Is Better

Another addition to the ACSM recommendations is the notion that “more is better”. The minimum exercise recommendations are just that—minimal. More activity provides more benefits and will further reduce risks for chronic diseases. Of course, people should use common sense when it comes to exercise and injury. Older people, or those with health problems, should also be more careful, and should incorporate activities that improve balance. Working with a qualified trainer can help you avoid problems.


Building and maintaining muscle mass is desirable for just about everyone. Protein intake provides the building blocks, and resistance training tells the muscles to grow. Protein does not have to come from fancy or expensive sources, as the recent milk research shows. And if you prefer a chocolate-flavored post-workout beverage, your trainer won’t object.



1 Hartman JW et all. Consumption of Fat-Free fluid milk after resistance exercise AmJClinNutr 2007 Aug;86(2):373-81.
2 Phillips SM Dietary protein to support anabolism J.AmCollNutr 2005 Apr;24(2):134S-139S.
3 Karp JR. Chocolate milk as a post-exercise recovery aid. Int J Sport Nutr Exerc Metabo 2006 Feb;16(1):78-91.

*This article is intended for general information purposes only, is not individual-specific, nor is it intended to replace the advice of your healthcare team.