I'm a male, 18 years old, 5 foot 8.5 inches, 140 lb. I'm currently building up mileage, 2 workouts and 60-65 miles a week. My PR is 15:10 from last summer, and I ran a 15:40 5k a couple weeks ago in 98 degree weather. I'm feeling pretty good training-wise at the moment.
Not eating a ton (eating about the same as I did in HS, when I wasn't running as much, I'd guess ~2700 calories a day), and most of it healthy, yet I'm the fattest I've ever been! I'm not just "fat" for a runner, I am seriously more chubby-looking than the average man my age. And yet, on the trails, I destroy all my training partners who look the part of decent runners.
What is wrong with me? How is it physically possible for me to be fat despite training hard and fast? I want to be as fast as possible, so I don't want this extra crap hindering me. Yet I also hate that I'm plagued with a constant anxiety about eating now, which I never had to deal with in the past. The obscene amount of thought I devote to my eating habits seems to only make things worse though; I feel like I've been getting fatter, even as I keep running more!
Some other things that might be pertinent; I dealt with a huge injury which sidelined me from running on/off my first college school-year, and thus this is my second month back consistently training. My resting heart rate is 47 bpm (used to be 52-56 in HS), and my normal body temperature is about 97.0.