I have seen and heard many stories where parents of gifted students are afraid to have their children participate in a physical activity or a sports team. There are a variety of reasons, from being afraid that they will get injured, to failure to see sports as a productive use of time. However, physical activity is a good idea for gifted students for a number of reasons, the least of which is exercise.
First, sports are good because they allow your gifted student to network with people outside of their normal peer group. The people that they will meet will be varied in their intellect and knowledge of the world, and the experience that your gifted student will receive by interacting with different people is valuable. Your gifted student will learn valuable communication skills that will serve them through out their life. Often communication is a weak point for gifted students, so the chance to practice with other kids of varying intellect is very valuable.
Second, sports help students cope with school. I know that the activity that I look forward to through out the day is my Volleyball practice. Even though school may not be going the way that I would like, I can get through the day because I know that I can have a great time for two hours during my Volleyball practice. By giving your gifted students something to look forward to outside of school, you are giving them an opportunity to clear their head and think of something other than their education for awhile.
Lastly, sports will give your gifted student the opportunity to get out and play. Similar to the last reason, this is very important because often times a gifted student is bogged down with responsibilities. They may feel that they have to live up to numerous expectations including their own. This is no mean feat, and the opportunity to act like a normal kid is very valuable. When a gifted student can go out and just have fun, they are able to perform their best in all the other areas of their life.
I hope that this post has given you a little perspective on why I think that sports are beneficial for gifted students. Because of the many demands that teachers, parents, and they themselves heap upon them, gifted students need the opportunity to vent and have fun.