I've always been a bit bulky for a runner, in high school and college I was about 145-150 lbs at 5'8. I've been out of college for 5 years and have kept training, still pretty close to my college PRs in fact. For the first 4 years after college I was able to keep the weight in the low 150s, occasionally getting up to 155 when not paying attention to diet. But this past year I've shot up to 160+ and I have no idea why. I don't binge eat at all, I only eat when hungry (3 good meals with 2-3 snacks per day). As a matter of fact, last year was the most mileage I've ever done, yet I'm fatter than ever. And no, I don't think I put on muscle, because I don't lift weights much, plus looking in the mirror I just look fat and puffy. My clothes are getting tighter and I feel uncomfortable most of the time. However, I haven't slowed down at all this year, in fact I just ran a pretty good race this last weekend, 16:50 for 5K on a course that I hadn't ever broken 17 on during the last few years. I was 162 when I weighed myself that morning.
I had my doctor check my blood to see if maybe I was hypothyroid, but the results were all normal. So I'm running more than ever, eating the same, running fast (for me), but I'm fat as sh*t. Does anyone have any experience with this?