Comfortable at just below your critical speed: how is blood flow distribution coupled to muscle fibre recruitment during exercise?

摘要

It is a common experience for every one of us that exercising at a fast yet comfortable pace, running, cycling or basically whatever exercise discipline, can be continued for a considerable duration without overt fatigue. However, if you just slightly increase the pace, the perceived effort is substantially enhanced and the tolerable duration of exercise is usually dramatically reduced. It is this exercise physiology phenomenon that has created the critical speed (CS), or power, concept (Jones et al. 2010), which together with gas exchange threshold, maximal oxygen consumption, and exercise efficiency dictates exercise performance or intolerance in health and disease.