By Candace Chemtob, B.S. and M.S. in Human Nutrition
The indelible image of Rocky Balboa gulping down a dozen raw eggs helped perpetuate the long held belief that eating a high protein diet leads to a muscular body. The emphasis that many athletes, coaches, and trainers place on dietary protein is based on the misguided logic “muscle is made of protein, therefore if I eat lots of protein, I will be muscular.” If it was this simple, we would see lots of people walking around looking like the famous, fictional boxer.
To start, let’s talk about the basics of protein metabolism. Proteins are long chains of amino acids. Your body consists of approximately 12 to 15% protein, referred to as lean body mass. Lean body mass comprises the structure of most body organs, blood cells, immune factors, hair, skin, and muscle mass (which is 65% of total lean body mass). The human body is in constant flux of breaking down and re-synthesizing proteins.
Unlike fat, and carbohydrates, there are no stores of protein in your body. This means that you need to eat protein rich foods every day to maintain your lean body mass. The Recommended Dietary Allowance (RDA) for protein is 0.8 g protein per kg body weight (for example, a 150 pound adult= 55g protein per day). However, the average American eats far in excess of this, 70 g per day for females and 100 g protein per day for males.
Recent studies have shown that athletes have higher protein requirements than sedentary adults. Intense training triggers an increase in protein breakdown. In fact, experts recommend increasing protein intake by 50 to 75% for athletes versus sedentary adults. Specifically, the protein requirements of adults participating in high intensity sports, like squash, is set at 1.2 to 1.4 g protein per kg (this means in a 150 pound adult= 82 to 95 g protein per day). The goal for protein intake is even higher for athletes engaged in several hours of resistance (weight) training per day (up to 1.8 g protein per kg).
Increased protein requirements are the result of accelerated protein breakdown during intense training. The additional protein in an athlete’s diet is needed to rebuild and repair muscle mass. As with most things in life, timing is important here. There is a window of opportunity, up to about 2 hours after working out, to stimulate protein synthesis— the rebuilding of muscles. This can be accomplished by consuming a small amount of protein (8 g protein, the amount in one ounce of meat or 8 ounces of milk) along with the carbohydrates. Protein and carbohydrates, when consumed together, have a synergistic effect on protein synthesis. Eating protein foods alone does not have the same effect. Carbohydrates trigger insulin release, which in turn stimulates protein synthesis.
Let’s go back to the fact that the average American consumes 70 to 100 g protein per day. This means that most athletes are already consuming enough protein to cover their increased needs. In fact, in my experience it is rare to come across an athlete with a protein deficient diet with the exception of vegetarian athletes and athletes (especially women) who are restricting their overall intake (for the purpose of weight reduction). The take home message here is: chances are you don’t need to be downing protein shakes or bars (these are the equivalent of Rocky’s eggs) to supplement your diet. In fact, if you eat protein in excess of your needs, it will be altered and ultimately enter the same energy cycles as fat and carbohydrates. To go one step further, I recommend staying away from products that tout an altered amino acid content (like increased branched chain amino acids, increased leucine or glutamine, etc). Beware of these products. You need all the amino acids to repair and build muscle and nothing man made can rival the amino acid patterns found in whole foods, such as meats, fish, poultry, dairy products, soy, and eggs.
As I mentioned at the beginning of the article, meeting or exceeding your protein needs alone will not lead to a rock hard, or Rocky-like body. Physiologically, our bodies are more complicated than this. Here are some tips for increasing your muscle mass:
1. The first ingredient to increase muscle mass is training, and hard training!
2. Secondly, are factors over which you have no control (age, male or female, genetics) which predetermine the levels of naturally occurring anabolic hormones and steroids circulating in your body.
3. However, you can use sports nutrition to optimize your body composition and here is how:
a. Your energy (calorie) intake needs meet your total energy expenditure. In other words, you need to be eating enough calories to meet your basic energy needs (resting metabolic rate, growth, lifestyle activity) plus the energy demands of squash, which can be up to 1,000 calories per hour. If you are restricting calories to lose weight (presumably fat weight), you will not be accruing muscle mass.
b. Secondly, since your brain and part of your nervous system run off exclusively carbohydrates, if you severely restricted the carbohydrates in your diet, the protein you consume will not be used for protein synthesis. As much as you may like your muscles, your body will prioritize and pick the brain every time. Even worse, your muscle mass will be sacrificed, converted into carbohydrates, and sent to your brain.
c. Meet your daily protein needs (as outlined above): 1.2 to 1.4 g protein per kg if you are training intensely or up to 1.8 g protein per kg if you are weight training for several hours per day.