Stress
Is there anything more stressful than confrontation? It's hard to get more confrontational than attempting to throw an unwilling person onto a mat. We'd ask you to test this theory, but that would be hideously irresponsible. Take our word for it.
Once you've been recruited and made the team, winning becomes everything. A wrestler is his record. It matters who you beat and how often. You better watch your back; any loss can irreparably damage your future as a wrestler.
And don't forget to study hard. Your grades are of paramount importance if you want to keep your roster spot or scholarship or, you know, stay in school. If you concentrate too much on your sport, you're liable to lose your eligibility to compete. This also means that parties, or really any social activities at all, are something you hear about from other people. When you're not in class, you'll always be in the weight room, on the track, on the mat, or in the library. Sorry, champ.