Hi, i have been training for a marathon this summer, and am also trying to sustain muscle mass. i am wondering if it is better to have protein intake before or after a run?
Carbs before, protein after. Also try drinking a sports drink or gel with a 4:1 carb/protein ratio, like acellerade while you run. I do distance running too and this has seemed to work great for me.
You need some protein yes but after your run you should really get some fast digesting carbs in too to help your muscles recover nice and quick and replenish your glycogen stores.