How to Determine How Much Protein to Eat for Exercise

Many athletes and exercisers think they should increase their protein intake to help them lose weight or build more muscle. Since muscles are made of protein, it makes sense that consuming more could help you reach your strength goals. It is true that the more you exercise, the greater your protein needs will be. However, there is a point at which you can take it too far. At a certain point—doubling your protein intake—there are likely diminishing returns.

Protein Intake Guidelines

Proteins are the basic building blocks of the human body. They are made up of amino acids and are needed for muscles, blood, skin, hair, nails, and internal organs. Next to water, protein is the most plentiful substance in the body, and most of it is actually in the skeletal muscles.

Considering this, it's reassuring to know that many experts believe that most of people get more than enough protein daily. In fact, some believe the average sedentary American eats about 50 percent more than the recommended daily amount, which ranges from 40 to 70 grams depending on your sex, age, and health condition.

If you're an exerciser, however, your protein needs may be higher since resistance training and endurance workouts can rapidly break down muscle protein.

If you are trying to build more muscle, you may think you need even more protein, but this probably isn't the case. There's evidence that bodybuilders, much like exercisers or athletes, do require more protein but that any more than double the recommended daily allowance won't necessarily help you build more muscle.

While the above guidelines give you a good sense of where your protein intake should fall, calculating the amount of daily protein that's right for you can help you fine-tune this further.

To determine your protein needs in grams (g), first calculate your weight in kilograms (kg) by dividing your weight in pounds by 2.2.

Next, decide how many grams of protein per kilogram of body weight is appropriate for you.

• Use the low end of the range if you are in good health and are sedentary: 0.8g per kg.
• Use a higher number (between 1.2 and 2.0) if you are under stress, pregnant, recovering from an illness, or if you are involved in consistent and intense weight or endurance training.

(You may need the advice of a doctor or nutritionist to help you determine this number.)

Then multiply your weight in kg times the number of protein grams per day.

Example:

154-pound (lb) male who is a regular exerciser and lifts weights, but is not training at an elite level:

• 154 lb/2.2 = 70 kg
• 70 kg x 1.7 = 119 grams protein per day

Another way to calculate how much protein you need is by using daily calorie intake and the percentage of calories that will come from protein.

First, determine how many calories your body needs each day to maintain your current weight:

• Find out what your basal metabolic rate (BMR) is by using a BMR calculator (sometimes referred to as a basal energy expenditure, or BEE, calculator).
• Determine how many calories you burn through daily activity and add that number to your BMR.

Next, decide what percentage of your diet will come from protein. The percentage you choose will be based on your goals, fitness level, age, body type, and metabolic rate. Most experts recommend that protein account for somewhere between 15 percent and 30 percent.

Multiply that percentage by the total number of calories your body needs for the day to determine total daily calories from protein.

Finally, divide that number by 4.

Example:

For a 140-pound female who consumes 1800 calories per day eating a diet composed of 20 percent protein:

• 1800 x 0.20 = 360 calories from protein
• 360 calories / 4 = 90 grams of protein per day

Foods that contain all of the essential amino acids are called complete proteins. These foods include beef, chicken, fish, eggs, milk, and just about anything else derived from animal sources.

Incomplete proteins don't have all of the essential amino acids and generally include vegetables, fruits, grains, seeds, and nuts. If you're a vegetarian or vegan, this doesn't mean you can't get complete protein, however.

This chart lists some incomplete proteins. To get all of the essential amino acids, simply choose foods from two or more of the columns.

No matter what your calculations are, remember that the foundation of any exercise program—whether your goal is to lose weight or gain muscle—is a combination of strength training, cardio activity, and a healthy diet that includes carbs, with a balance of protein and fat.