eli5 – What is a persons “second wind”, and what are the physiological processes involved in getting it?

Question

You often hear of athletes or sports persons getting a “second wind”, how is this?

In: 26

Answer 1

I do some pretty intense cardio from time to time. If I lose track of my breathing I can end up in a situation where my blood oxygen level is sub-optimal. If I am aggressively making use of this supply, this will become apparent in minutes. Once I correct this issue my performance will return to baseline.