Asked in Yawning
Why do you yawn while working out?
June 04, 2009 6:18AM
Well, for one thing we don't even know WHY we yawn.
A quite plausible theory is that we yawn to get more oxygen because our tired bodies can't gain enough through normal breathing.
Another one is that it's a way to relieve tension and stress.
Yawning is almost always a sign of sleepiness and is common in the morning or late at night. When you work out remember to have plenty of rest, food and water beforehand.