Originally Posted by SATennis
You do have to be careful of the weight room at an early age. Lifting heavy weights when your body hasn't has a chance to develop can stunt your growth, but playing tennis seriously definitely will not.
Playing contact sports is 10x more stressful on bones and growth plate areas than lifting weights. If you do it under the guidance of a certified professional, the stress on bones is even less. I really wish people would stop giving weights such a bad rep and idly passing on knowledge they've heard from people on message boards and their peers.