“For example, on a long, hard run, the physiological, psychological, and mental fatigue associated with a maximum effort sends a danger signal to the body. What started out as a chosen and desired effort is interpreted as life threatening, something to be stopped. Your first response will not be a conscious sense of fear but rather physiological sensations. At this point, in fact, your conscious mind is still giving you full-steam-ahead signals, but the subconscious mind, intent on life preservation, begins sending the body an opposite set of instructions—muscle stiffness and pain, pounding heart, a struggle to breathe, sounds suggestive of dying. The message from the subconscious mind to the body is clear—shut it down.”