With a plethora of sports blogs and information circulating the internet, it can be difficult to discern truth from myth, especially on the topic of nutrition and sports performance. As an ACE Nutrition Specialist with a focus on Sports Performance and as a former Category 2 Road Cyclist, I thought it'd be helpful to clarify some things and hopefully shed light on the truth about protein and its effect on sports performance.
Before and During Workout
To encourage positive nitrogen balance (which ensures muscle synthesis, hydration, and adequate energy), athletes should consume a combination of carbohydrates and protein in a ratio of 3:1 -- this ratio should be maintained both before, during, and after exercise. Protein intake during exercise has been shown to have benefits on performance, so long as the digestive system can handle it. (For many endurance athletes, protein is not easily digested during these longer activities). In particular, branched-chain amino acids (BCAAs) have been shown to combat fatigue during endurance events.
It is essential that athletes are consuming enough carbohydrates. For example, if a marathon runner consumes a diet high in protein but insufficient in carbohydrates to support her runs, her body will rely heavily on her own muscle protein for fuel.
Post-Workout
The same ratio of carbs to protein (3:1) should be maintained after exercise. Consumption of protein immediately following exercise (within 15 to 30 minutes) helps in the repair and synthesis of muscle proteins. Furthermore, it is recommended that 6 to 20g of protein be consumed with 30 to 40g of carbohydrates within 3 hours post-exercise. Research indicates that as little as 5 to 10g of protein immediately after exercise can promote optimal muscle repair. If only protein is consumed without sufficient carbohydrates to meet the body's energy needs, then muscle synthesis may be compromised.
Some good snacks post-workout include milk with fruit or a tbsp of honey, Greek yogurt with fruit or granola, orange juice mixed with a scoop of whey protein, or a turkey sandwich. It's important to consume the right foods to ensure all essential amino acids are included -- for example, banana and peanut butter will not include all essential amino acids (read here for more information on amino acids).
Whey
Whey, ho! Whey protein is a popular post-workout powder and for good reason: whey, which is one of the two major milk proteins, contains high levels of the amino acid leucine. Leucine plays an important role in muscle hypertrophy (muscle growth). It is rapidly digested and has a remarkable ability to stimulate muscle protein synthesis.
But not all whey is created equal. Whey powder is 11% to 15% protein and is used as an additive in many food products. Whey concentrate is 25% to 89% protein, and whey isolate is 90+% protein. Isolate is also the only whey version that is lactose-free. Obviously, the choice here for rebuilding of muscles post-workout is the isolate, but be careful: some of the proteins can be lost during the manufacturing process. Main takeaway: do your research on the quality of the whey isolate brand.
Hungry for more? Be sure to check out my blog post on Protein 411!