<P> This is the case even without exercise in people with respiratory disease, challenged circulation of blood to parts of the body or any other situation when oxygen cannot be supplied to the tissues involved . </P> <P> Some people's bodies may take more time than others to be able to balance the amount of oxygen they need to counteract the lactic acid . This theory of the second wind posits that, by pushing past the point of pain and exhaustion, runners may give their systems enough time to warm up and begin to use the oxygen to its fullest potential . For this reason, well - conditioned Olympic - level runners do not generally experience a second wind (or they experience it much sooner) because their bodies are trained to perform properly from the start of the race . </P> <P> The idea of "properly trained" athlete delves into the theory of how an amateur athlete can train his or her body to increase the aerobic capacity or aerobic metabolism . A big push in Ironman Triathlon ten years ago introduced the idea of heart rate training and "tricking" one's body into staying in an aerobic metobolic state for longer periods of time . This idea is widely accepted and incorporated into many Ironman Triathlon training programs . </P> <P> Endorphins are credited as the cause of the feeling of euphoria and wellbeing found in many forms of exercise, so proponents of this theory believe that the second wind is caused by their early release . Many of these proponents feel that the second wind is very closely related to--or even interchangeable with--the runner's high . </P>

Where did the term second wind come from