Catching your second wind

[Oso]

I know this phenomena to be true but never really thought about it.

Anyone have a physiological explanation for it?

[Ming Yue]

I've read a couple ideas. One, that it's attributed to reaching max efficiency. Eg., it might take 20 minutes for your heart rate and blood flow to speed up enough to match the increased oxygen demand of your muscles, giving you sudden max efficiency and a seeming burst of energy.

the other is an increase in the release of beta endorphins, and/or psychological stimuli - roar of the crowd, willpower, anger...

[FngSaiYuk]

Yep, most of the stuph I've come across indicates that the 'second wind' is the point at which your body switches to a more efficient form of energy delivery -



No matter how fit individuals are, the first few minutes into vigorous exercise may cause their muscles to ache and make them somewhat out of breath. The body isn't able to transport oxygen to the active muscles quickly enough. As a result, the muscles burn carbohydrates anaerobically, causing an increase in lactic acid production. Gradually, the body makes the transition to aerobic metabolism, and begins to burn nutrients (carbohydrates and fats) aerobically. This shift to aerobic metabolism coincides with the "second wind." The more people train and the more fit they become, the sooner they will get their "breath" back. Then they will reach aerobic levels they can sustain for extended durations.


Bunch of factors involved of course, but that's the gist of it.

[Ford Prefect]

Yes. Do a search on Circulo-resparatory distress.