The energetics during the world most challenging mountain ultramarathon: a case study

The energy requirements during ultra-endurance events are likely to be at the extremes ofhuman tolerance (Millet and Millet, 2012). This is of further importance for extreme mountain ultra-marathon (MUM), where the ultra-long distance performance is coupled to run and/or walk on mountain trails with considerable positive and negative elevation change. For instance, it was shown that after the world’s most challenging MUM the energy cost of uphill running decreased, likely due to changes in the uphill-running step mechanics that lead to a ‘smoother’ and more economical running style (Vernillo et al., 2013). However, that study focused only on longitudinal (i.e., pre-post) changes. Thus, there are few data examining the physiological changes during a MUM with a high fatiguing potential in ecologically valid environments. Accordingly, we report the case of an experienced MUM runner who was participating in the world’s most challenging MUM with the aim to provide the first data about the energy requirements as well as the physiological adaptations of MUM.