I’m a competing distance runner at my high school and although I’m good, I’m by no means the best. This summer I’m hoping to change that and really push myself to get ahead, but there’s one thing that I know has impeded me and that is my muscle mass. I’m completely lean muscle, with a low body fat, yet I have a large amount of upper body muscle mass, particularly in the chest. My coach has said that I need

to lose that muscle as it in no way contributes to my racing. I know what i need to do once I hit the roads all I need to know is, how do I lose the upper body through targeted, systematic dieting? My goal is to get down to 120 by the end of the summer and I would also like to know if that’s unrealistic.

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How Do I Lose Muscle Through Systematic Dieting? [Forum]