The following is from a gem of abook called Secret of Success. This useful book, was written by William Walker Atkinson.
Early on in the book he discusses the power of a mental second wind. This is power that we can tap into at will. We just need to learn to discover it and let it work for us.
The majority of you know by actual experience in everyday life that we have within our physical organism that which we call “second-wind.” We have essayed some physical task, and after a bit found ourselves “winded,” that is short of breath, and we are tempted to stop and rest our panting bodies.
But, we have also found by experience that if we will stick to the task at hand the feeling of physical distress will usually pass away, and we will gain what is called our “second-wind.” Now just what this “second-wind” is, is a matter that has long perplexed physiologists, and even today they have not been able to hand us down a very good guess at the underlying cause of the phenomenon.
It seems to be a fresh start acquired by reason of the opening up of reserve stores of vital energy – latent physical power stored away for such emergencies. All persons who have engaged in athletic sports know very well the details of this peculiar physiological phenomenon – its actuality is too firmly established to admit any doubt.
And, as is often the case, examination shows a curious parallel between the working of Nature on the mental plane and on the physical. Just as there is a physical “second-wind,” so is there a mental reserve force or latent energy upon which we can draw and thus get a fresh start.
The phenomena attendant upon physical “second-wind,” as noted above, is almost exactly duplicated by certain mental phenomena. We may be jaded while performing some tedious bit of mental work, and we begin to feel that we are “all in,” when lo! Some new in – and away we are off with a full mental “second-wind” doing our work with a freshness, vigor and enthusiasm far surpassing the original effort. We have tapped into a fresh source or supply of mental energy.”