Ask A Pro: Why Does Swimming Make Me So Sleepy?]

By Samantha McGlone via Triathlete magazine

Q: After my morning swim practice I am absolutely exhausted, more so than in any other sport. Why does swimming make me so sleepy?

For my entire triathlon career I have wondered the exact same thing! Growing up as a runner, I would usually feel great after a long run—my body was tired, but I was mentally alert. Once I started swimming, I could barely keep my eyes open after practice. My organic chemistry grade from the year I swam with my college swim team can attest to this fact—unfortunate scheduling placed this (already tedious) class immediately after our two-hour morning swim practice. I would race to lecture straight from the pool at 8 and, once the adrenaline of sprinting across campus wore off, it was only a matter of minutes before my eyes drooped and my head started bobbing like a chicken.