I know several personally, but I hate using personal anecdotes as evidence. These people religiously run 45-55 miles a week (slightly below your number, I know,

I know several personally, but I hate using personal anecdotes as evidence. These people religiously run 45-55 miles a week (slightly below your number, I know, but there is nothing magical about those last 5 miles). They also run a slow 50. But, they still run around 50 a week and they are overweight. The point being there is nothing magical about running long distances and being lean, IMO. Someone could (and like I said, I know several) run that and be overweight). I know plenty of people who ride bikes 150-200+ miles a week and are overweight. What I suspect you mean when you say 50mpw is that someone running 50mpw at 5 min/mile pace (or less) is not going to be overweight. And that is probably true. But you are factoring in intensity then, which changes the equation entirely. For instance, I know someone that lifts weights 4 times a week for 1 hour a day and is fat. He's been doing it for years. I also know someone who lifts weights 4 times a week for 1 hour a day and just won a local bodybuilding contest. There are so many things I didn't say in the above it isn't worth talking about them? What are they eating? What does their workout look like? Are they both lifting the same weights? How intense are they working out? Adequate sleep in both cases? Any sprinting? Like I said, I suspect what you meant in the 50mpw case was also something about intensity, not just distance.