What Determines Endurance Performance
For years onlookers have marvelled at outstanding sports performances, while coaches, athletes and scientists have wondered what sets those performers apart. Vast amounts of research has examined determinants of endurance performance in trained and untrained individuals. Coaches and governing bodies have used the resulting data to identify talent and structure training. The purpose of this essay is to explore key determinants and how they interact to create such performances.
Endurance is defined as the ability to resist fatigue for the longest time possible (Hurdiel, et all., 2018). It can be evaluated by recording the power or velocity that can be maintained for a period of 30 minutes up to four hours (Coyle, 1999). For endurance sports, extensive research has been carried out resulting in three common factors appearing to play key roles in performance. These are maximal oxygen consumption (VO2max), economy of movement (EoM) and lactate threshold (LT) (Joyner & Coyle, 2008). Each are indicators of performance potential and provide valuable insight to aid the structure of training. This essay will cover each of these, evaluating the influence that each has on determining endurance performance.
Maximal Oxygen Uptake (VO2max)
VO2max can be defined as the maximum integrated capacity of the pulmonary, cardiovascular and muscular systems to uptake, transport and utilise oxygen (Poole et al., 2008). It is one of the main metrics used in the field of exercise physiology to indicate cardiorespiratory fitness of athletes, predict performance and influence training (Mazzoleni et al., 2017; Midgley, McNaughton & Wilkinson, 2006).
Foster (1983) stated that VO2max has typically been considered the best laboratory measure for determining performance. However, it is now considered a better indicator of upper performance limit, as a person is not able to operate above 100% VO2max for long periods (Faude, Kindermann & Meyer, 2009), leaving potential for variables to determine actual performance.
The fractional utilisation of VO2max can provide further insight into performance (Bassett & Howley 2000). The velocity at a percentage of VO2max, known as performance VO2max (PVO2max) is likely a more useful indicator than VO2max. This will be influenced by other physiological and biomechanical traits. By examining PVO2max an early understanding of EoM of an athlete can be constructed.
Economy of Movement (EoM)
EoM is recognised as the oxygen uptake required to achieve a given velocity. From EoM, PVO2max can be established to measure the aerobic demand of velocity.
EoM can be influenced by a number of physiological and biomechanical factors. Examples include increased mitochondria and oxidative enzymes within the muscle. Other adaptions, such as the muscles ability to store and release elastic energy through increased muscle stiffness and improved mechanics could elicit better EoM.
Interventions to improve EoM are frequently sought after. The utilisation of strength training and high or simulated altitude training environments are most common (Saunders et al., 2004).
As a determinant of endurance performance, EoM could be considered more accurate than VO2max as it details a narrower range of possible outcome. Potential for improvements in EoM and knowledge of an athletes VO2max can be combined to understand current fitness levels and establish a relatively accurate, although not definite, prediction of performance.
When testing EoM, there are outside variables that can affect the result. Research suggests fatigue level of the test subject as being influential (Mier et al., 2012). Recent injury history and location within current training could also be influential.
In attempts to identify accurate sub-maximal performance indicators, testing has more recently led to LT being identified as an indicator, more indicative of endurance performance (Faude., et al. 2009)
Lactate Threshold (LT)
LT, more importantly velocity at LT, could be argued to be the most accurate endurance determinant. As with EoM, ability to influence LT with training is high. Having knowledge of velocity, heart rate or percentage of VO2max at which LT inflection takes place is valuable when constructing training programs.
As a performance determinant LT is effective at integrating the upper limit of VO2max and the biomechanical determinant of EoM by generating an accurate point demonstrating muscle stress. Reflecting back to PVO2max and the increased benefit over just maximal output, LT has an affect here. According to research the percentage of VO2max that can be maintained during an endurance event depends on the level of lactate accumulation (Rønnestad & Mujika, 2014). When studying LT alongside VO2max, it is noted by Coyle (2008) that untrained subjects displayed an upturn in blood lactate concentration at ~60% of VO2max. In comparison to trained athletes where this same upturn occurs between 75%-90%. It could be argued that appropriate training can produce greater performance improvements in utilising more of an athletes VO2max than by trying to increase VO2max. Maximal uptake is still relevant and could be used to identify potential in untrained subjects.
Conclusion As independent determinants, testing VO2max, EoM and LT all provide a view of an athlete’s endurance ability. The performance potential and the training that should be prescribed can also be established from analysing these tests.
Combining the metrics could provide results more indicative of actual performance outcome. For example, studying EoM can explain the performance difference between athletes with similar VO2max. It provides evidence to support study findings where the athlete with the highest VO2max does not necessarily perform best (Bassett & Howley, 2000). Studying VO2max alone could lead to a distorted belief of performance. A superior VO2max is proven to be advantageous in endurance events but can be overcome by the ability to sustain a high percentage of a lesser VO2max. Undertaking training to complement VO2max is vital for developing the ability to be efficient and to delay lactate accumulation. Combining the data allows the window of potential performance to be narrowed and a clearer overall picture of the athlete to be established.
These appear to be the most commonly used determinants for endurance performance. All play a role in performance and the prescription of training to best develop an athlete. Testing should be carried out at intervals within a training program to ascertain progress.
Each method shows the athlete’s current capability. Testing would most accurately determine performance when undertaken after a successful period of training, having maintained the relevance of training through periodical testing. This would allow the subject the opportunity to develop the ability to sustain high levels of VO2max and accrue the necessary volume of specific training to address EoM needs.
Other factors can also play a part in determining athletic performance that this essay has not touched upon. The psychological component being one area that is increasingly being studied. Genetics being another factor to be considered. Ongoing research will develop knowledge that continues to deliver awe inspiring performances for years to come.
Coyle, E. F. (1999). Physiological determinants of endurance exercise performance. Journal of Science and Medicine in Sport, 2(3), 181-189.
Joyner, M. J., & Coyle, E. F. (2008). Endurance exercise performance: the physiology of champions. The Journal of Physiology, 586(1), 35–44.
Poole, D. C., Wilkerson, D. P., & Jones, A. M. (2008). Validity of criteria for establishing maximal O2 uptake during ramp exercise test. European Journal of Applied Physiology, 102, 403–410.
Bassett, D. R. JR., & Howley, E. T. (2000). Limiting factors for maximum oxygen uptake and determinants of endurance performance. Medicine & Science in Sports & Exercise, 32(1), 70.
Daniels, J. (1985). A physiologist’s view of running economy. Medicine & Science in Sports & Exercise, 17(3), 332–338.
Saunders, P. U., et al. (2004). Factors Affecting Running Economy in Trained Distance Runners. Sports Medicine, 34, 465–485.
Foster, C. (1983). VO2 max and training indices as determinants of competitive running performance. Journal of Sports Sciences, 1, 13-22.
Hurdiel, R., et al. (2018). Cognitive performance and self-reported sleepiness are modulated by time-of-day during a mountain ultramarathon. Research in Sports Medicine,1-8.
Faude O, Kindermann W, Meyer T. (2009). Lactate Threshold Concepts. Sports Medicine, 39, 469–490.
Mazzoleni, M. J., et al. (2017). A dynamical systems approach for the submaximal prediction of maximum heart rate and maximal oxygen uptake. Sports Engineering, 21(1), 31-41.
Midgley, A. W., McNaughton, L. R., & Wilkinson, M. (2006). Is there an Optimal Training Intensity for Enhancing the Maximal Oxygen Uptake of Distance Runners? Sports Medicine, 36(2), 117-132.
Rønnestad, B. R., & Mujika, I. (2013). Optimizing strength training for running and cycling endurance performance: A review. Scandinavian Journal of Medicine & Science in Sports, 24(4), 603-612.
Mier, C. M., Alexander, R. P., & Mageean, A. L. (2012). Achievement of VO2max criteria during a continuous graded exercise test and a verification stage performed by college athletes. Journal of Strength and Conditioning Research, 26(10), 2648-2654.