I have started to think that body shape is very much influenced by the work one does. Most guys here are lean, but then again most guys here have been climbers or loggers for a good portion of their working careers. Climbing punishes large people, so you will be inclined to be very fit while not bulking up. Logging is almost the same, walking miles and miles keeping a quick pace will reward leanness, but the chainsaw work and hauling rigging will reward both leanness and muscle bulk. I know a man who is amazing at pipeline laboring. He's a big guy, 6'3 or so, with arms the size of my legs. He has a bit of a gut, because walking isn't needed that much honestly, and size is greatly rewarded in the working conditions that are experienced here. When i explain him to others, i say take the 5 best laborers you have ever met, glue them together, and that's this guy. He will work all day with hardly a break, in extreme heat or cold, rain, you name it. He works at a very fast pace, and is so strong he simply just overpowers stuff if he has to. He is paid very handsomely for his efforts, way over what scale would be even though he is a working supervisor. His gut does not interfere with his job, so it likely won't go away. I eat way more than he does, and have a bit of a gut myself, but there's no way i could even comes close to doing the amount of manual labor this dude does all day every day. He basically is the best laborer/ spread boss I've ever even heard about, and his body has developed as it has to handle this.
Like a blacksmith from back in the day will likely eventually become a hulking brute, i have seen that ones job will determine their shape and size. I can tell how long someone had been in the trades by how they walk and move, and i can usually tell what their profession was. I know nothing of martial arts, but those guys didn't have to perform manual labor all their lives, so their fitness is determined by what they did in the weight room, which would appear to be not very much. But just because someone has a bit of a gut doesn't mean they are fat and lazy. I will admit their nutrition is likely off tho, as I've noticed on myself living on the road like i have.