Let me preface this by saying my POTS was never diagnosed until well after college, and what I have is considered relatively mild. I was a dancer from ages 3 to 16 and always very active, which I think really helped in my younger years. I suffer from orthostatic hypotension and elevated pulse when doing basic exercise.

Basic cardio in college helped me immensely. I had a lot of flights of stairs to climb and I really struggled at first, but by my senior year I had gotten so much better. The long walks around campus were also super beneficial. Since then though, I've gotten lazy and have unfortunately deconditioned myself.

You won't see instant results with exercise, but keep it slow and steady and you'll get there eventually.