Why Protein is Vital to Athletes

Working at PowerBar I get the privilege of working alongside some pretty fantastic scientists. And they are always available to answer questions and give any info I might need. Usually when I am doing a nutrition clinic, or I am at an event, and someone asks a question, I love that I generally have the answer, or can get the answer from them. Sometimes I get a bit of skepticism that I am just giving a “corporate  answer,” or an answer that PowerBar wants me to say. I’m not, but doing this IOC program is definitely validation. Over the course of the month, we have spent hours on protein. Pretty much anything you could want to know about it. And I’m happy to report, everything we went over this month, was exactly the same thing PowerBar has been saying. One example is, we use three different types of protein, the IOC program recommends the three proteins, in the same amounts. Validation!

Protein seems to be the hot new topic today. And for good reason too. It’s vital for athletes to take in enough protein for muscle growth and muscle repair, along with other important body functions like building bone, cartilage and blood. I’m not going to focus on high protein diets, paleo diets, weight loss, etc. That’s not my goal of this article. The goal is to help to educate on why, how much and what kinds should we be taking in. First, let’s look at the definition of protein.

Protein: (from Wikipedia)

Proteins are large biological molecules, or macromolecules, consisting of one or more chains of amino acid residues.
Amino Acids:
The building blocks of protein.


Why should we be taking in protein? The two things that I am going to focus on muscle growth and repair. Post exercise is a very important time for protein consumption, and I’m going to say the most important time too.

  • Muscle protein synthesis is doubled after exercise and will continue to stay up for 48 hours post exercise.  So we help muscle protein synthesis by taking in protein, soon after exercise. I like to say 20-30min post exercise, but at least within an hour.
  • When exercising, you are actually stimulating muscle breakdown, if you don’t consume protein post exercise, you will stay in a negative balance. If you consume protein, you will reverse the muscle breakdown and stimulate synthesis.
  • Ingestion of carbohydrates post exercise will also stop muscle breakdown due to stimulating insulin. The release of insulin prohibits muscle breakdown. Carbohydrates will not promote synthesis though, only protein

How Much?

  • Post exercise, 20-25g of protein seems to be the ideal range for athletes who are in a normal caloric range. If you are actively trying to lose weight, and are in a negative caloric balance, 30g is thought to be better.
  • Also, taking the 25g of protein in at once, is thought to be better than taking it spread over time. One study we looked at examined athletes taking a bolus of 25g, or taking 10×2.5g over the course of the day. There is no difference in the amount of amino acids the muscles will see, however the bolus promoted greater muscle synthesis.
  • During the day in your daily diet, the RDA (recommended daily allowance) is currently at .8g/kg/day. This is too low for athletes, especially athletes doing resistance exercise. New research recommends getting at least 1.4-1.5g/kg/day with up to 2g/kg/day for strength based athletes.

What Types?

  • Dairy proteins are superior to soy or other plant-based proteins. Specifically whey protein is the most superior protein due to the fact that it has the highest amounts of the amino acid leucine in it. Luecine is the metabolic trigger for protein synthesis.
  • In a study done by Sarah B Wilkinson et al, 18g of protein from dairy, and 18g of protein from soy milk was examined. The soy milk was isonitrogenous and isoenergetic, meaning it was designed to mimic dairy. The study showed that those athletes consuming the milk protein had a greater muscle synthesis and repair to the soy drinking athletes.
  • So when they promote chocolate milk, there is an actual scientific basis for it. Enjoy, just enjoy the lower fat versions. And only post exercise due to the amounts of sugar added.
  • Also, plant-based proteins are good sources of protein, but have a higher caloric cost. This means, you have to eat a lot more, to get the same benefits.

The study looked at 25g of protein from 4 sources

  • 3oz of lean beef = 180 kcal
  • 1.5 cups of raw tofu = 236 kcal
  • 3 servings of black beans = 374 kcal
  • 7 tbsp peanut butter = 670 kcal

So, the lean meat provided the fewest calories for the same amounts of protein. I like to eat plant-based meals, however I will continue to eat my whey protein in my recovery drinks, protein bars, cottage cheese, yogurts and more, so I can get these benefits.

Other Things:

  • The three types of proteins that are recommended are Whey, Casein and Soy. Each digest at a different rate, so each provides benefits. Whey is the fastest digesting and has all the amino acids we need. Soy is slower digesting and does not have all the amino acids our bodies need (specifically leucine). Casein is the slowest digesting, however can be sped up if it is hydrolyzed. All three proteins are important to us.
  • While I’m talking about soy, you can forget the myth that you as a man will be given too much psuedo estrogen, you won’t.
  • Taking protein in before exercise (in a weight lifting study) showed that protein is available right after exercise. For endurance athletes, taking protein right before can upset your stomach, so I wouldn’t. I would take in protein asap after exercise.
  • There was one study we looked at that showed that during ultra exercise (over 6 hours), taking in some protein can help you post exercise because it starts protein synthesis, not because there was a performance benefit. This can be upsetting on an athletes stomach, so if you want to try this I would keep your protein to less than 10g per hour.
  • A pilot study (very small), looked at the benefit of taking amino acids in during exercise. The amounts of a.a. taken during the study are very high, and much higher than any commercially available sports nutrition product touts. So, if you’re trying to consume a.a. in your bars, gels, drinks, etc. You aren’t getting enough a.a. to make it beneficial.
  • Amino acids post exercise are crucial though. Leucine is obviously the biggest one we learned about, but I would include the BCAAs (branch chain amino acids) and glutamine. The BCAA’s are leucine, isoleucine and valine. BCAAs are essential, meaning your body can’t make them, you must eat them from other sources. The  BCAAs have been shown to increase muscle protein synthesis and help prevent breakdown.

So, what happens if you don’t drink milk?

If you are unlucky to be have a milk allergy, or follow a diet like paleo, you want to make sure you are getting in your BCAA’s, specifically leucine. I would speak with your doctor first, but I have seen upwards of 3-5g in protein powders. Foods that contain leucine (other than whey) include eggs, seaweed, soy and meat.

Wrap Up:

  • Whey is the best source of protein for muscle synthesis due to its high amounts of leucine
  • Consume 1.4-2g/kg/day of protein depending on your sport
  • Take a protein based food or drink immediately after exercise-20-30g depending on your caloric intake
  • Protein during exercise can help to start protein synthesis, but won’t improve your performance
  • Take a BCAA with glutamine if you can’t do dairy sources, or if you just want to make sure you are getting proper recovery

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