The chances are you may drift away from some of them. I know that from my working career, it is often difficult to keep in touch with people you used to know at a previous job. Sports can be all consuming and are therefore similar in a way. But you can certainly make an effort to keep in touch. See if there are things you can arrange to do together in the summer or during the year, outside sports and studies. Go bowling, biking, hang out someplace (someone's home, pizza place, park, wherever), go to concerts.
You don't have to lose your friends, but you don't need to worry about losing them either. Sometimes new directions bring new friends. That's the nature of life. But any friend that's really close will keep popping up regardless, so enjoy whatever you've decided to do and see what happens!!