Sports/Martial Arts

No specifics - The MC is short, overweight, and constantly abused by bullies. When he moves to a new school, he fears that the vicious cycle will start once more. However, one awkward haircut changes his life. He wakes up the next morning to find he has two bodies, one normal, the other handsome and athletic.

This one isn't specifically about sports or martial arts, but there are a good number of scenes sprinkled throughout. Humor is top notch and the MC is extremely relatable.