Physiological and biological factors associated with a 24 h treadmill ultra‐marathon performance

Abstract

The purpose of this study was to examine the physiological and biological factors associated with ultra-endurance performance. Fourteen male runners volunteered to run on a treadmill as many kilometers as possible over a 24-h period (24TR). Maximal oxygen uptake (VO(2max)), velocity associated with VO(2max)(VO(2max)) and running economy (RE) at 8 km/h were measured. A muscle biopsy was also performed in the vastus lateralis muscle. The subjects ran 149.2 ± 15.7 km in 18 h 39 ± 41 min of effective attendance on the treadmill, corresponding to 39.4 ± 4.2% of . Standard multiple-regression analysis showed that performance was significantly (R(2) = 0.82; P = 0.005) related to VO(2max) and specific endurance, i.e. the average speed sustained over the 24TR expressed in . VO(2max) was associated with a high capillary tortuosity (R(2) = 0.66; P = 0.01). Specific endurance was significantly related to RE and citrate synthase activity. It is concluded that a high VO(2max) and an associated developed capillary network are essential for ultra-endurance running performance. The ability to maintain a high %VO(2max) over a 24TR is another factor associated with performance and is mainly related to RE and high mitochondrial oxidative capacity in the vastus lateralis.

Physiological and jump performance alterations induced by a dramatic increase in running volume. A case study. (Alteraciones fisiológicas y de capacidad de salto inducidas por un dramático aumento de volumen de carrera. Un estudio de caso)

“…These chronic adaptations are in accordance with the acute power reduction verified after a 10-km running race (Gómez et al, 2002). The decrease in lower-limbs explosive power that was found in our study despite the negative effect on jumping performance wasn't reflected in running performance perhaps due to the increased mechanical efficiency provoked by alterations in gait pattern (Eriksson et al, 2011) or higher metabolic efficiency (Millet et al, 2011) induced by long-lasting workouts.…”

“…This is in accordance with our data which demonstrated running economy improvement with a significant reduction in muscle power. Besides higher mitochondrial oxidative capacity, performance in ultra-endurance events is mainly related to running economy (Millet et al, 2011), which corroborates the most significant physiological adaptations verified in this study. It seems that running economy improves independently of running intensity when running volume is significant (Enoksen et al, 2011), which was the main characteristic of the training protocol in this study.…”

Factors affecting energy cost of running during an ultra-endurance race

“…Davies and Thompson (Davies and Thompson, 1986) observed a linear increase of V · O2,max with time from the 50th to 240th minute during a 4 h race on a treadmill at constant speed, the rise becoming significant (P<0.01) after 110 min of exercise. In addition, the ability to maintain a high F over a 24 h treadmill run was found to be mainly related to a low CoT (Gimenez et al, 2013;Millet et al, 2011), and in the same study participants a significant change in running biomechanics, including higher oscillation frequency, lower vertical stiffness and lower ground reaction force (GRF), was observed . Indeed, interventions to reduce CoT are constantly sought by athletes, coaches and sport scientists.…”

Participation and performance trends in 6-hour ultra-marathoners – a retrospective data analysis of worldwide participation from 1991-2010

“…The relationship between variables of physiology (Lazzer et al, 2011, Millet et al, 2011, cognition (Parry et al, 2011), anthropometry (Knechtle et al, 2010a(Knechtle et al, , 2010b, training (Knechtle et al, 2010a(Knechtle et al, , 2010b, pre-race experience (Knechtle et al, 2010a(Knechtle et al, , 2010b, gender (Lepers & Maffiuletti, 2011) and age ) with performance in ultra-endurance running competitions have been investigated. In 24-hours treadmill ultra-marathon performance, maximum oxygen uptake (VO2max) and the ability to run at a high %VO2max over time seemed to be the main physiological parameters correlated with better performance (Millet et al, 2011).…”

“…In 24-hours treadmill ultra-marathon performance, maximum oxygen uptake (VO2max) and the ability to run at a high %VO2max over time seemed to be the main physiological parameters correlated with better performance (Millet et al, 2011). Furthermore, it appeared that anthropometric characteristics such as body mass (Knechtle et al, 2010a(Knechtle et al, , 2010b, body height (Knechtle et al, 2010a), body mass index (Knechtle et al, 2010a(Knechtle et al, , 2010b, percent body fat (Knechtle et al, 2010a(Knechtle et al, , 2010b, circumferences of limbs (Knechtle et al, 2010a(Knechtle et al, , 2010b) and thicknesses of skin-folds (Knechtle et al, 2010a) showed no correlation with race performance in ultra-endurance competitions, while previous experience (Knechtle et al, 2011b, Herbst et al, 2011, training and especially training intensity (Knechtle et al, 2010a(Knechtle et al, , 2010b on the other hand highly correlated with race performance.…”