American football — snug fit a must. Like in baseball and softball, American football players need plenty of firm protection around their heels. The fit should allow the player’s toes to move, but fit snugly, since foot support for the quick, zigzag movement is a must to prevent twisted ankles.
Tennis — a little toe room, please. Tennis, like basketball, requires that players leap up to make winning plays. About ¼ to ½ inch toe room allows the foot to expand as the player jumps up. Allow some free play at the heel without slippage.