Everywhere. Need Help?. Increase lean muscle mass and you'll perform, look and feel better. Why?. Sabrina Grotewold is the running editor for active.com.
Maybe the reason a marathon runner is so skinny and doesn't have any muscle is because they're not trying to build any muscle and they don't have much .
Since then, athletes have become bigger, stronger, leaner, and more specialized. Muscle quality is a broad measure of the relative amount of connective and .