Your son could probably do this at a school where both the athletics and the music are semi-serious but clearly secondary in everyone’s eyes (coaches, conductors, peers) to academics. So probably not a D-I school. Time in the lab will also cut into flexibility for co-curricular activities.
A friend of mine was a 4.0 chemical engineering student, played in the (very low key) orchestra, and spent all his free time at the gym, and he made it work, but he never traveled for competitions or had to peak for any other particular purpose because he was a highly motivated fitness hobbyist without commitments to teammates or a coach. This also wouldn’t have been possible if he had struggled in any of his courses, which most engineering students do at one point or another (or all the time). My friend is now a physician.
If the goal is to run because your son loves it and play music because he loves it that’s great and maybe he can make it work. But he also may find that it’s too hard to juggle (that’s okay) or he wants to be exceptional at something which requires giving up something else (also okay) or his interests may change entirely (also okay). The great thing about exploring options this young is he can learn about what’s out there and still have time to figure things out.