by Chad Kerksick PhD February 25, 2011 3 min read
You hear a lot about whey protein and for a person who has a particular interest in its effects on our muscle with and without exercise; I continue to be amazed with its power. Just for a quick review, resistance exercise increases growth of muscle proteins. No kidding, you don’t say? Without nutrients, the increase of muscle breakdown goes up more than increases in muscle protein. As a result, the balance between growth of muscle and loss of muscle remains negative. Not good!!!!
How do you change it?
Add some nutrients….any kind of nutrients. For example, even giving carbohydrate after exercise decreases muscle proteinbreakdown. Studies say that carbohydrates after exercise doesn’t increase muscle growth, but it does help lessen the amount of protein breakdown (and replenish lost glycogen) which to contributes to overall recovery and when you combine that with whey protein it can add up to a HUGE difference in muscle growth over time.
When protein and amino acids are provided, muscle protein synthesis increases to a great extent and this flips the balance between muscle growth and muscle balance to an overwhelmingly positive level resulting in an accumulation of muscle proteins. That’s a good thing!
A really well-done study provided nice outcomes which outlines the impact of feeding on changes in muscle protein synthesis. In addition the same study also highlighted how the combination of both nutrition and exercise influence changes in muscle protein synthesis (Moore et al. 2009). Young college guys completed a standard bout of resistance exercise with only one leg before consuming a single 25 gram dose of whey protein isolate. Effectively, this type of study allows for an assessment of the impact of feeding without exercise and feeding along with exercise. Assessments of muscle protein synthesis were completed one, three and five hours after the exercise bout was completed. So what impact did the exercise and whey protein have on changes in blood amino acid levels and muscle protein synthesis? Firstly, increases in blood essential amino acids occur rapidly. In fact, within 30 minutes of ingesting a single 25 gram dose of whey protein isolate, blood essential amino acid levels increased and peaked one hour after ingestion.
These changes alone are important. Growth of muscle proteins are driven by increases in amino acid levels; a fact which has been shown previously in a number of studies. When optimal levels of amino acids are available, this provides the necessary components to put the body in a position where muscle growth can occur. Of course, changes in blood amino acid levels are important, but everyone is ultimately interested in what extent muscle growth changed. This is where it gets even more convincing in favor of whey protein. Protein increases were monitored one, three and five hours after completing an exercise bout and ingesting whey protein and changes in key proteins found inside muscle was increased at all time points. Interestingly enough when just the protein was ingested, with no exercise, muscle protein synthesis was increased as well, but only one hour after the exercise bout.
In summary, the power of whey protein is great indeed. When a single dose of high quality whey protein is ingested without any form of exercise, the growth of specific muscle proteins was found to occur up to three hours after whey protein was consumed. However, when you combine an exercise bout, the positive influence of whey protein is magnified to an even greater extent than without exercise. What to take away from all of this? Grabbing a quick dose of high quality whey protein can do wonderful things to increase muscle growth. Its important to remember that a single dose of protein only increases amino acids levels in the blood for two to three hours after you consume it and these values must stay elevated for growth to occur. However, if you want to dial things up a notch or two regarding muscle growth, take your dose of high quality whey protein after your workout and you’ll see an increase in muscle growth for another two hours or for up to five hours after the workout. Add fast acting carbohydrates to that post workout dose of whey protein and you’re likely setting yourself up for a best-case scenario in terms of potential muscle gain. Increasing muscle mass is not an easy thing and it comes down to how well you can balance the favorable impact of whey protein ingestion with resistance exercise.