Physiological Demands of Running During Long Distance Runs and Triathlons

The aim of this review article is to identify the main metabolic factors which have an influence on the energy cost of running (Cr) during prolonged exercise runs and triathlons. This article proposes a physiological comparison of these 2 exercises and the relationship between running economy and performance. Many terms are used as the equivalent of ‘running economy’ such as ‘oxygen cost’, ‘metabolic cost’, ‘energy cost of running’, and ‘oxygen consumption’. It has been suggested that these expressions may be defined by the rate of oxygen uptake (.VO2) at a steady state (i.e. between 60 to 90% of maximal.VO2) at a submaximal running speed.