Cant speak on wrestling but theres no weight cutting for football and id imagine that's a huge part of what makes wrestling practice hard. I had a friend who was pretty dominant in wrestling and he would wear a trash bag under his clothes everyday. Exploding from a three point stance and moving another human being while trying to diagnose where the ball is going and finding the quickest way to get to the play is exhausting. Then, you run back to the huddle, get the next call and get lined up again. Theres maybe 8 to 10 seconds to breathe before you get back down in that 3 point stance and explode again.