Advice for Athlete at Ivy - STEM Major

Freshman at Ivy having walked onto the varsity squad for my sport. Also managed to get a smaller finance club as well. I'm thinking I'd like to major in math and focus on applied math because it seems the most interesting and intellectually stimulating but with the practice schedule starting to set in I'm also open to considering a major in something much less rigorous (econ or business). Any advice in terms of timeline (applications for freshman internships) or major or anything like that? Thought I knew what I was doing but not anymore.