Q: I just started lifting weights. Should I be eating lots of extra protein to help build muscle?
A: When people begin exercising, they often think that they should eat a lot of protein to support muscle building. High school athletes, in particular, may start utilizing protein supplements to “bulk up.” But for adults who are starting an exercise program or who want to increase their activity, do they need lots of protein?'
The Recommended Daily Allowance (RDA) for protein is 0.35 gram/kg body weight. This is for an adult who does not exercise. So for an inactive woman who weighs 150#, that works out to about 53 grams of protein per day. That’s the starting point to avoid deficiency. You might have already noticed that body weight influences the amount of protein that you need. A person who weighs 250 pounds needs more protein than a person who weighs only 125!
Active adults need more protein. However, it’s important to remember that the exercise itself (weight lifting, other resistance training) is more effective in building muscle than protein is. Protein helps repair muscles after a workout, but the actual workout is what builds muscle strength. Here are some guidelines based on activity level.
Sedentary, no purposeful exercise: .35 g/lb. Body weight
Moderately Active, 2-5 times a week (brisk walking, lawn work, golfing): .5 g/lb. Body weight
Endurance Activity, >2 hours per week of running, biking, or swimming: .55-.65 g/lb. Body weight
Resistance Activity, >2 hours per week of high intensity resistance exercising, weightlifting: .7-1.0 g/lb. Body weight
For those who eat a balanced diet that includes meat, poultry, fish, dairy products, or eggs, most don’t have trouble meeting these protein requirements. For athletes who are vegetarians or vegans, meeting protein needs takes a little more effort and planning, but it can be done. Beans, nut butter, and soy are all good sources of protein. Most recreational athletes do not need shakes or other protein supplements. Instead, make sure you include a source of food protein at each meal or snack. For example, eggs or peanut butter at breakfast, chicken or tuna at lunch, nuts or Greek yogurt at snack, and fish for dinner.
Eating too much protein isn’t dangerous (if you have healthy kidneys). It just serves no purpose. You won’t get bigger muscles more quickly by overloading on protein. Instead, your body will just use it as fuel.