Hi guys, I'm a junior in high school. I was just wondering if I should do track for senior year in the 1600 and 3200 or train for a marathon for next January. I've never done track/XC, but I've ran plenty of road 5ks and 1 mile t-t in the past year. My PBs are 5:35 for the mile, and 19:45 for the 5k. My current millage is 25-30 mpw, but I'm planning to average 50+ mpw in the summer for buildup training. And if any of you guys have any advice on how to build muscle mass while running 30+ mpw, that would be great. Thanks Letsrun forum.