Went for a 10K run after my pool workout this morning. Started the run off at a pretty decent pace, around 8:00/mile, which is my normal base-training pace. Started out feeling fine, began to lag a little at about half way, slowed the pace a little, then felt that second wind kick in and finished strong. Can anyone explain what goes on in the body that causes that new burst of energy that we’ve all experienced called “second wind”? Anyone know where that term came from? Just curious.
the wonders of google (its almost scary) came up with this suggestion from www.drmirkin.com/archive/7037.html:
When you run very fast, you become short of breath and feel like you have to slow down, but if you keep on pushing yourself, you suddenly feel refreshed and can pick up the pace. Do you know what caused your sudden recovery?
It’s called second wind and you don’t even know that your recovery is caused by slowing down when you feel exhausted during exercise. When you exercise intensely, your muscles use large amounts of oxygen. You can run so fast that your muscles require more oxygen than you can breathe in through your lungs and you develop an oxygen debt that causes lactic acid to accumulate in your muscles. This makes your muscles acidic, which causes pain and burning/ and the lactic acid spills over into your bloodstream, causing you to gasp for air. You finally reach a point where you can’t meet your needs for oxygen, which forces you to slow down. You don’t notice that you have slowed down because you are working just as hard as you did when you were running at a faster pace. Not only must you bring in extra oxygen to meet your present needs, you must also use some of the oxygen to make up for the debt that you incurred when you were running at a faster pace.
Eventually, you catch up on your oxygen debt and feel better. So, you pick up the pace and don’t even know that it was the slower running that revived you. You think that there was a change in your metabolism and you call it, second wind.
By Gabe Mirkin, M.D., for CBS Radio News
Seems like this answer fits your morning run experience, but not the “second wind” i sometimes get (other than when I eat two chipoltle burritos in a row) when I go out for a long aerobic run at 150-155bpm. After about 45-60min sometimes my HR drops to 145 or even 140 and I know that my pace has not dropped that much. Although maybe that phenomenon is not “second wind” but something else?
Thanks. I have to remember to Google whenever I have a question. I agree, very scary. So scary, in fact, that I may have to buy some of their stock when they do their IPO. I wonder if taking deeper breaths when you experience that “fatigue” will get more oxygen into your system and speed up the recovery process. Or do you just hyperventilate and pass out?