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Limits of Ultra: Towards an Interdisciplinary Understanding of Ultra-Endurance Running Performance

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Abstract

Ultra-endurance running (UER) poses extreme mental and physical challenges that present many barriers to completion, let alone performance. Despite these challenges, participation in UER events continues to increase. With the relative paucity of research into UER training and racing compared with traditional endurance running distance (e.g., marathon), it follows that there are sizable improvements still to be made in UER if the limitations of the sport are sufficiently understood. The purpose of this review is to summarise our current understanding of the major limitations in UER. We begin with an evolutionary perspective that provides the critical background for understanding how our capacities, abilities and limitations have come to be. Although we show that humans display evolutionary adaptations that may bestow an advantage for covering large distances on a daily basis, these often far exceed the levels of our ancestors, which exposes relative limitations. From that framework, we explore the physiological and psychological systems required for running UER events. In each system, the factors that limit performance are highlighted and some guidance for practitioners and future research are shared. Examined systems include thermoregulation, oxygen delivery and utilisation, running economy and biomechanics, fatigue, the digestive system, nutritional and psychological strategies. We show that minimising the cost of running, damage to lower limb tissue and muscle fatigability may become crucial in UER events. Maintaining a sustainable core body temperature is critical to performance, and an even pacing strategy, strategic heat acclimation and individually calculated hydration all contribute to sustained performance. Gastrointestinal issues affect almost every UER participant and can be due to a variety of factors. We present nutritional strategies for different event lengths and types, such as personalised and evidence-based approaches for varying types of carbohydrate, protein and fat intake in fluid or solid form, and how to avoid flavour fatigue. Psychology plays a vital role in UER performance, and we highlight the need to be able to cope with complex situations, and that specific long and short-term goal setting improves performance. Fatigue in UER is multi-factorial, both physical and mental, and the perceived effort or level of fatigue have a major impact on the ability to continue at a given pace. Understanding the complex interplay of these limitations will help prepare UER competitors for the different scenarios they are likely to face. Therefore, this review takes an interdisciplinary approach to synthesising and illuminating limitations in UER performance to assist practitioners and scientists in making informed decisions in practice and applicable research.

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References

  1. Knechtle B, Nikolaidis PT. Physiology and pathophysiology in ultra-marathon running. Front Physiol. 2018;9:634. https://doi.org/10.3389/fphys.2018.00634.

    Article  PubMed  PubMed Central  Google Scholar 

  2. Scheer V. Participation trends of ultra endurance events. Sports Med Arthrosc Rev. 2019;27(1):3–7. https://doi.org/10.1097/jsa.0000000000000198.

    Article  PubMed  Google Scholar 

  3. Scheer V, Basset P, Giovanelli N, Vernillo G, Millet GP, Costa RJ. Defining off-road running: a position statement from the Ultra Sports Science Foundation. Int J Sports Med. 2020;41(05):275–84.

    Article  PubMed  Google Scholar 

  4. DUV GUAe-. Ultra marathon statistics. May 3, 2023 [cited; Available from: https://statistik.d-u-v.org/. Accessed 3 May 2023.

  5. Cejka N, Rust CA, Lepers R, Onywera V, Rosemann T, Knechtle B. Participation and performance trends in 100-km ultra-marathons worldwide. J Sports Sci. 2014;32(4):354–66. https://doi.org/10.1080/02640414.2013.825729.

    Article  PubMed  Google Scholar 

  6. Hoffman MD, Ong JC, Wang G. Historical analysis of participation in 161 km ultramarathons in North America. Int J Hist Sport. 2010;27(11):1877–91. https://doi.org/10.1080/09523367.2010.494385.

    Article  PubMed  Google Scholar 

  7. Knechtle B, Scheer V, Nikolaidis PT, Sousa CV. Participation and performance trends in the oldest 100-km ultramarathon in the world. Int J Environ Res Public Health. 2020. https://doi.org/10.3390/ijerph17051719.

    Article  PubMed  PubMed Central  Google Scholar 

  8. Hoffman MD. State of the science on ultramarathon running after a half century: a systematic analysis and commentary. Int J Sports Physiol Perform. 2020;23:1–5. https://doi.org/10.1123/ijspp.2020-0151.

    Article  Google Scholar 

  9. Jones AM, Kirby BS, Clark IE, Rice HM, Fulkerson E, Wylie LJ, et al. Physiological demands of running at 2-hour marathon race pace. J Appl Physiol (1985). 2021;130(2):369–79. https://doi.org/10.1152/japplphysiol.00647.2020.

    Article  CAS  PubMed  Google Scholar 

  10. Joyner MJ. Modeling: optimal marathon performance on the basis of physiological factors. J Appl Physiol (1985). 1991;70(2):683–7. https://doi.org/10.1152/jappl.1991.70.2.683.

    Article  CAS  PubMed  Google Scholar 

  11. Joyner MJ, Hunter SK, Lucia A, Jones AM. Physiology and fast marathons. J Appl Physiol (1985). 2020;128(4):1065–8. https://doi.org/10.1152/japplphysiol.00793.2019.

    Article  PubMed  Google Scholar 

  12. Balducci P, Clemencon M, Trama R, Blache Y, Hautier C. Performance factors in a mountain ultramarathon. Int J Sports Med. 2017;38(11):819–26. https://doi.org/10.1055/s-0043-112342.

    Article  PubMed  Google Scholar 

  13. Belinchon-deMiguel P, Ruisoto P, Knechtle B, Nikolaidis PT, Herrera-Tapias B, Clemente-Suarez VJ. Predictors of athlete’s performance in ultra-endurance mountain races. Int J Environ Res Public Health. 2021. https://doi.org/10.3390/ijerph18030956.

    Article  PubMed  PubMed Central  Google Scholar 

  14. Coates AM, Berard JA, King TJ, Burr JF. Physiological determinants of ultramarathon trail-running performance. Int J Sports Physiol Perform. 2021;10:1–8. https://doi.org/10.1123/ijspp.2020-0766.

    Article  Google Scholar 

  15. Garbisu-Hualde A, Santos-Concejero J. What are the limiting factors during an ultra-marathon? A systematic review of the scientific literature. J Hum Kinet. 2020;72:129–39. https://doi.org/10.2478/hukin-2019-0102.

    Article  PubMed  PubMed Central  Google Scholar 

  16. Knechtle B, Knechtle P, Rosemann T, Lepers R. Predictor variables for a 100-km race time in male ultra-marathoners. Percept Mot Skills. 2010;111(3):681–93. https://doi.org/10.2466/05.25.Pms.111.6.681-693.

    Article  PubMed  Google Scholar 

  17. O’Loughlin E, Nikolaidis PT, Rosemann T, Knechtle B. Different predictor variables for women and men in ultra-marathon running-the Wellington Urban Ultramarathon 2018. Int J Environ Res Public Health. 2019. https://doi.org/10.3390/ijerph16101844.

    Article  PubMed  PubMed Central  Google Scholar 

  18. Pastor FS, Besson T, Varesco G, Parent A, Fanget M, Koral J, et al. Performance determinants in trail-running races of different distances. Int J Sports Physiol Perform. 2022;25:1–8. https://doi.org/10.1123/ijspp.2021-0362.

    Article  Google Scholar 

  19. Best R, Barwick B, Best A, Berger N, Harrison C, Wright M, et al. Changes in pain and nutritional intake modulate ultra-running performance: a case report. Sports (Basel). 2018. https://doi.org/10.3390/sports6040111.

    Article  PubMed  PubMed Central  Google Scholar 

  20. Tiller NB, Elliott-Sale KJ, Knechtle B, Wilson PB, Roberts JD, Millet GY. Do sex differences in physiology confer a female advantage in ultra-endurance sport? Sports Med. 2021;51(5):895–915. https://doi.org/10.1007/s40279-020-01417-2.

    Article  PubMed  Google Scholar 

  21. Bozek K, Wei Y, Yan Z, Liu X, Xiong J, Sugimoto M, et al. Exceptional evolutionary divergence of human muscle and brain metabolomes parallels human cognitive and physical uniqueness. PLoS Biol. 2014;12(5): e1001871. https://doi.org/10.1371/journal.pbio.1001871.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  22. Altmann J, Schoeller D, Altmann SA, Muruthi P, Sapolsky RM. Body size and fatness of free-living baboons reflect food availability and activity levels. Am J Primatol. 1993;30(2):149–61. https://doi.org/10.1002/ajp.1350300207.

    Article  PubMed  Google Scholar 

  23. Simmen B, Bayart F, Rasamimanana H, Zahariev A, Blanc S, Pasquet P. Total energy expenditure and body composition in two free-living sympatric lemurs. PLoS ONE. 2010;5(3): e9860. https://doi.org/10.1371/journal.pone.0009860.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  24. Thompson ME. Comparative reproductive energetics of human and nonhuman primates. Annu Rev Anthropol. 2013;42(1):287–304. https://doi.org/10.1146/annurev-anthro-092412-155530.

    Article  Google Scholar 

  25. Kraft TS, Venkataraman VV, Wallace IJ, Crittenden AN, Holowka NB, Stieglitz J, et al. The energetics of uniquely human subsistence strategies. Science. 2021;374(6575):0130. https://doi.org/10.1126/science.abf0130.

    Article  CAS  Google Scholar 

  26. Folk GE Jr, Semken HA Jr. The evolution of sweat glands. Int J Biometeorol. 1991;35(3):180–6. https://doi.org/10.1007/bf01049065.

    Article  PubMed  Google Scholar 

  27. Lieberman DE. Human locomotion and heat loss: an evolutionary perspective. Compr Physiol. 2015;5(1):99–117. https://doi.org/10.1002/cphy.c140011.

    Article  PubMed  Google Scholar 

  28. Bramble DM, Lieberman DE. Endurance running and the evolution of Homo. Nature. 2004;432(7015):345–52. https://doi.org/10.1038/nature03052.

    Article  CAS  PubMed  Google Scholar 

  29. Pickering TR, Bunn HT. The endurance running hypothesis and hunting and scavenging in savanna-woodlands. J Hum Evol. 2007;53(4):434–8. https://doi.org/10.1016/j.jhevol.2007.01.012.

    Article  PubMed  Google Scholar 

  30. Lieberman D. The story of the human body: evolution, health, and disease. 1st ed. New York: Pantheon Books; 2013.

    Google Scholar 

  31. Hora M, Pontzer H, Wall-Scheffler CM, Sladek V. Dehydration and persistence hunting in Homo erectus. J Hum Evol. 2020;138:102682. https://doi.org/10.1016/j.jhevol.2019.102682.

    Article  PubMed  Google Scholar 

  32. Pontzer H. Ecological energetics in early Homo. Curr Anthropol. 2012;53(S6):S346–58. https://doi.org/10.1086/667402.

    Article  Google Scholar 

  33. Lieberman DE. Is exercise really medicine? an evolutionary perspective. Curr Sports Med Rep. 2015;14(4):313–9. https://doi.org/10.1249/jsr.0000000000000168.

    Article  PubMed  Google Scholar 

  34. Pontzer H, Durazo-Arvizu R, Dugas LR, Plange-Rhule J, Bovet P, Forrester TE, et al. Constrained total energy expenditure and metabolic adaptation to physical activity in adult humans. Curr Biol. 2016;26(3):410–7. https://doi.org/10.1016/j.cub.2015.12.046.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  35. Thurber C, Dugas LR, Ocobock C, Carlson B, Speakman JR, Pontzer H. Extreme events reveal an alimentary limit on sustained maximal human energy expenditure. Sci Adv. 2019;5(6):eaaw0341. https://doi.org/10.1126/sciadv.aaw0341.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  36. Gurven MD, Lieberman DE. WEIRD bodies: mismatch, medicine and missing diversity. Evol Hum Behav. 2020;41(5):330–40. https://doi.org/10.1016/j.evolhumbehav.2020.04.001.

    Article  PubMed  PubMed Central  Google Scholar 

  37. Gurven MD, Trumble BC, Stieglitz J, Yetish G, Cummings D, Blackwell AD, et al. High resting metabolic rate among Amazonian forager-horticulturalists experiencing high pathogen burden. Am J Phys Anthropol. 2016;161(3):414–25. https://doi.org/10.1002/ajpa.23040.

    Article  PubMed  PubMed Central  Google Scholar 

  38. Jones AM, Burnley M, Black MI, Poole DC, Vanhatalo A. The maximal metabolic steady state: redefining the “gold standard.” Physiol Rep. 2019;7(10): e14098. https://doi.org/10.14814/phy2.14098.

    Article  PubMed  PubMed Central  Google Scholar 

  39. Billat V, Vitiello D, Palacin F, Correa M, Pycke JR. Race analysis of the world’s best female and male marathon runners. Int J Environ Res Public Health. 2020. https://doi.org/10.3390/ijerph17041177.

    Article  PubMed  PubMed Central  Google Scholar 

  40. Schena F, Pellegrini B, Tarperi C, Calabria E, Salvagno GL, Capelli C. Running economy during a simulated 60-km trial. Int J Sports Physiol Perform. 2014;9(4):604–9. https://doi.org/10.1123/ijspp.2013-0302.

    Article  PubMed  Google Scholar 

  41. Millet GY, Banfi JC, Kerherve H, Morin JB, Vincent L, Estrade C, et al. Physiological and biological factors associated with a 24 h treadmill ultra-marathon performance. Scand J Med Sci Sports. 2011;21(1):54–61. https://doi.org/10.1111/j.1600-0838.2009.01001.x.

    Article  CAS  PubMed  Google Scholar 

  42. Howe CCF, Swann N, Spendiff O, Kosciuk A, Pummell EKL, Moir HJ. Performance determinants, running energetics and spatiotemporal gait parameters during a treadmill ultramarathon. Eur J Appl Physiol. 2021;121(6):1759–71. https://doi.org/10.1007/s00421-021-04643-2.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  43. Davies CT, Thompson MW. Aerobic performance of female marathon and male ultramarathon athletes. Eur J Appl Physiol Occup Physiol. 1979;41(4):233–45. https://doi.org/10.1007/bf00429740.

    Article  CAS  PubMed  Google Scholar 

  44. Waskiewicz Z, Klapcinska B, Sadowska-Krepa E, Czuba M, Kempa K, Kimsa E, et al. Acute metabolic responses to a 24-h ultra-marathon race in male amateur runners. Eur J Appl Physiol. 2012;112(5):1679–88. https://doi.org/10.1007/s00421-011-2135-5.

    Article  CAS  PubMed  Google Scholar 

  45. Clark IE, Vanhatalo A, Bailey SJ, Wylie LJ, Kirby BS, Wilkins BW, et al. Effects of two hours of heavy-intensity exercise on the power-duration relationship. Med Sci Sports Exerc. 2018;50(8):1658–68. https://doi.org/10.1249/mss.0000000000001601.

    Article  PubMed  Google Scholar 

  46. Fulco CS, Rock PB, Cymerman A. Maximal and submaximal exercise performance at altitude. Aviat Space Environ Med. 1998;69(8):793–801.

    CAS  PubMed  Google Scholar 

  47. Daniels JT. A physiologist’s view of running economy. Med Sci Sports Exerc. 1985;17(3):332–8.

    Article  CAS  PubMed  Google Scholar 

  48. Foster C, Lucia A. Running economy : the forgotten factor in elite performance. Sports Med. 2007;37(4–5):316–9. https://doi.org/10.2165/00007256-200737040-00011.

    Article  PubMed  Google Scholar 

  49. Gimenez P, Kerhervé H, Messonnier LA, Féasson L, Millet GY. Changes in the energy cost of running during a 24-h treadmill exercise. Med Sci Sports Exerc. 2013;45(9):1807–13. https://doi.org/10.1249/MSS.0b013e318292c0ec.

    Article  PubMed  Google Scholar 

  50. Sabater Pastor F, Varesco G, Besson T, Koral J, Feasson L, Millet GY. Degradation of energy cost with fatigue induced by trail running: effect of distance. Eur J Appl Physiol. 2021;121(6):1665–75. https://doi.org/10.1007/s00421-021-04624-5.

    Article  CAS  PubMed  Google Scholar 

  51. Barstow TJ, Mole PA. Linear and nonlinear characteristics of oxygen uptake kinetics during heavy exercise. J Appl Physiol (1985). 1991 Dec;71(6):2099–106.DOI: https://doi.org/10.1152/jappl.1991.71.6.2099.

  52. Bearden SE, Moffatt RJ. VO(2) kinetics and the O(2) deficit in heavy exercise. J Appl Physiol (1985). 2000;88(4):1407–12.DOI: https://doi.org/10.1152/jappl.2000.88.4.1407.

  53. Paterson DH, Whipp BJ. Asymmetries of oxygen uptake transients at the on- and offset of heavy exercise in humans. J Physiol. 1991;443:575–86. https://doi.org/10.1113/jphysiol.1991.sp018852.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  54. Jones AM, Burnley M. Oxygen uptake kinetics: an underappreciated determinant of exercise performance. Int J Sports Physiol Perform. 2009;4(4):524–32. https://doi.org/10.1123/ijspp.4.4.524.

    Article  PubMed  Google Scholar 

  55. Burnley M, Jones AM. Power-duration relationship: Physiology, fatigue, and the limits of human performance. Eur J Sport Sci. 2018;18(1):1–12. https://doi.org/10.1080/17461391.2016.1249524.

    Article  PubMed  Google Scholar 

  56. Grassi B, Rossiter HB, Zoladz JA. Skeletal muscle fatigue and decreased efficiency: two sides of the same coin? Exerc Sport Sci Rev. 2015;43(2):75–83. https://doi.org/10.1249/jes.0000000000000043.

    Article  PubMed  Google Scholar 

  57. de Waal SJ, Gomez-Ezeiza J, Venter RE, Lamberts RP. Physiological indicators of trail running performance: a systematic review. Int J Sports Physiol Perform. 2021;16(3):325–32. https://doi.org/10.1123/ijspp.2020-0812.

    Article  PubMed  Google Scholar 

  58. Lemire M, Falbriard M, Aminian K, Millet GP, Meyer F. Level, uphill, and downhill running economy values are correlated except on steep slopes. Front Physiol. 2021;12:697315. https://doi.org/10.3389/fphys.2021.697315.

    Article  PubMed  PubMed Central  Google Scholar 

  59. Whipp BJ, Rossiter HB, Ward SA. Exertional oxygen uptake kinetics: a stamen of stamina? Biochem Soc Trans. 2002;30(2):237–47.

    Article  CAS  PubMed  Google Scholar 

  60. Holloszy JO, Kohrt WM, Hansen PA. The regulation of carbohydrate and fat metabolism during and after exercise. Front Biosci. 1998;15(3):D1011–27. https://doi.org/10.2741/a342.

    Article  Google Scholar 

  61. Millet G, Lepers R, Lattier G, Martin V, Babault N, Maffiuletti N. Influence of ultra-long-term fatigue on the oxygen cost of two types of locomotion. Eur J Appl Physiol. 2000;83(4–5):376–80. https://doi.org/10.1007/s004210000313.

    Article  CAS  PubMed  Google Scholar 

  62. Vernillo G, Savoldelli A, Zignoli A, Skafidas S, Fornasiero A, La Torre A, et al. Energy cost and kinematics of level, uphill and downhill running: fatigue-induced changes after a mountain ultramarathon. J Sports Sci. 2015;33(19):1998–2005. https://doi.org/10.1080/02640414.2015.1022870.

    Article  PubMed  Google Scholar 

  63. Noakes TD, Lambert EV, Lambert MI, McArthur PS, Myburgh KH, Benade AJ. Carbohydrate ingestion and muscle glycogen depletion during marathon and ultramarathon racing. Eur J Appl Physiol Occup Physiol. 1988;57(4):482–9. https://doi.org/10.1007/bf00417997.

    Article  CAS  PubMed  Google Scholar 

  64. Martinez S, Aguilo A, Rodas L, Lozano L, Moreno C, Tauler P. Energy, macronutrient and water intake during a mountain ultramarathon event: the influence of distance. J Sports Sci. 2018;36(3):333–9. https://doi.org/10.1080/02640414.2017.1306092.

    Article  PubMed  Google Scholar 

  65. Berger N, Cooley D, Graham M, Harrison C, Best R. Physiological responses and nutritional intake during a 7-day treadmill running world record. Int J Environ Res Public Health. 2020. https://doi.org/10.3390/ijerph17165962.

    Article  PubMed  PubMed Central  Google Scholar 

  66. Clark IE, Vanhatalo A, Thompson C, Joseph C, Black MI, Blackwell JR, et al. Dynamics of the power-duration relationship during prolonged endurance exercise and influence of carbohydrate ingestion. J Appl Physiol (1985). 2019;127(3):726–36. https://doi.org/10.1152/japplphysiol.00207.2019.

    Article  CAS  PubMed  Google Scholar 

  67. Jeukendrup AE. Carbohydrate intake during exercise and performance. Nutrition. 2004;20(7–8):669–77. https://doi.org/10.1016/j.nut.2004.04.017.

    Article  CAS  PubMed  Google Scholar 

  68. Hoffman MD, Fogard K. Factors related to successful completion of a 161-km ultramarathon. Int J Sports Physiol Perform. 2011;6(1):25–37. https://doi.org/10.1123/ijspp.6.1.25.

    Article  PubMed  Google Scholar 

  69. Millet GY, Hoffman MD, Morin JB. Sacrificing economy to improve running performance–a reality in the ultramarathon? J Appl Physiol (1985). 2012;113(3):507–9. https://doi.org/10.1152/japplphysiol.00016.2012.

    Article  CAS  PubMed  Google Scholar 

  70. Foissac MJ, Berthollet R, Seux J, Belli A, Millet GY. Effects of hiking pole inertia on energy and muscular costs during uphill walking. Med Sci Sports Exerc. 2008;40(6):1117–25. https://doi.org/10.1249/MSS.0b013e318167228a.

    Article  PubMed  Google Scholar 

  71. Vernillo G, Millet GP, Millet GY. Does the running economy really increase after ultra-marathons? Front Physiol. 2017;8:783. https://doi.org/10.3389/fphys.2017.00783.

    Article  PubMed  PubMed Central  Google Scholar 

  72. Vernillo G, Giandolini M, Edwards WB, Morin JB, Samozino P, Horvais N, et al. Biomechanics and physiology of uphill and downhill running. Sports Med. 2017;47(4):615–29. https://doi.org/10.1007/s40279-016-0605-y.

    Article  PubMed  Google Scholar 

  73. Giandolini M, Vernillo G, Samozino P, Horvais N, Edwards WB, Morin JB, et al. Fatigue associated with prolonged graded running. Eur J Appl Physiol. 2016;116(10):1859–73. https://doi.org/10.1007/s00421-016-3437-4.

    Article  PubMed  Google Scholar 

  74. Morin JB, Samozino P, Millet GY. Changes in running kinematics, kinetics, and spring-mass behavior over a 24-h run. Med Sci Sports Exerc. 2011;43(5):829–36. https://doi.org/10.1249/MSS.0b013e3181fec518.

    Article  PubMed  Google Scholar 

  75. Morin JB, Tomazin K, Edouard P, Millet GY. Changes in running mechanics and spring-mass behavior induced by a mountain ultra-marathon race. J Biomech. 2011;44(6):1104–7. https://doi.org/10.1016/j.jbiomech.2011.01.028.

    Article  CAS  PubMed  Google Scholar 

  76. Khassetarash A, Vernillo G, Kruger RL, Edwards WB, Millet GY. Neuromuscular, biomechanical, and energetic adjustments following repeated bouts of downhill running. J Sport Health Sci. 2022;11(3):319–29. https://doi.org/10.1016/j.jshs.2021.06.001.

    Article  PubMed  Google Scholar 

  77. Wheeler PE. The loss of functional body hair in man: the influence of thermal environment, body form and bipedality. J Human Evol. 1985;14(1):23–8. https://doi.org/10.1016/S0047-2484(85)80091-9.

    Article  Google Scholar 

  78. Wheeler PE. The thermoregulatory advantages of hominid bipedalism in open equatorial environments: the contribution of increased convective heat loss and cutaneous evaporative cooling. J Human Evol. 1991;21(2):107–15. https://doi.org/10.1016/0047-2484(91)90002-D.

    Article  Google Scholar 

  79. Wheeler PE. The thermoregulatory advantages of large body size for hominids foraging in savannah environments. J Human Evol. 1992;23(4):351–62. https://doi.org/10.1016/0047-2484(92)90071-G.

    Article  Google Scholar 

  80. Carrier DR. The energetic paradox of human running and hominid evolution. Curr Anthropol. 1984;25(4):483–95.

    Article  Google Scholar 

  81. Bouscaren N, Millet GY, Racinais S. Heat stress challenges in marathon vs. ultra-endurance running. Front Sports Active Liv. 2019. https://doi.org/10.3389/fspor.2019.00059.

    Article  Google Scholar 

  82. Beal H, Corbett J, Davis D, Barwood MJ. Marathon Performance and Pacing in the Doha 2019 Women’s IAAF World Championships: Extreme Heat, Suboptimal Pacing, and High Failure Rates. Int J Sports Physiol Perform. 2022;17:1–7. https://doi.org/10.1123/ijspp.2022-0020.

    Article  Google Scholar 

  83. Hue O, Henri S, Baillot M, Sinnapah S, Uzel AP. Thermoregulation, hydration and performance over 6 days of trail running in the tropics. Int J Sports Med. 2014;35(11):906–11. https://doi.org/10.1055/s-0033-1361186.

    Article  CAS  PubMed  Google Scholar 

  84. Armstrong LE, Costill DL, Fink WJ. Influence of diuretic-induced dehydration on competitive running performance. Med Sci Sports Exerc. 1985;17(4):456–61. https://doi.org/10.1249/00005768-198508000-00009.

    Article  CAS  PubMed  Google Scholar 

  85. Cheuvront SN, Kenefick RW. Dehydration: physiology, assessment, and performance effects. Compr Physiol. 2014;4(1):257–85. https://doi.org/10.1002/cphy.c130017.

    Article  PubMed  Google Scholar 

  86. Hew-Butler T, Loi V, Pani A, Rosner MH. Exercise-associated hyponatremia: 2017 update. Front Med. 2017. https://doi.org/10.3389/fmed.2017.00021.

    Article  Google Scholar 

  87. Zouhal H, Groussard C, Minter G, Vincent S, Cretual A, Gratas-Delamarche A, et al. Inverse relationship between percentage body weight change and finishing time in 643 forty-two-kilometre marathon runners. Br J Sports Med. 2011;45(14):1101–5. https://doi.org/10.1136/bjsm.2010.074641.

    Article  PubMed  Google Scholar 

  88. Valentino TR, Stuempfle KJ, Kern M, Hoffman MD. The influence of hydration state on thermoregulation during a 161-km ultramarathon. Res Sports Med. 2016;24(3):212–21. https://doi.org/10.1080/15438627.2016.1191491.

    Article  PubMed  Google Scholar 

  89. González-Alonso J. Separate and combined influences of dehydration and hyperthermia on cardiovascular responses to exercise. Int J Sports Med. 1998;19(Suppl 2):S111–4. https://doi.org/10.1055/s-2007-971972.

    Article  PubMed  Google Scholar 

  90. Barwood MJ, Davey S, House JR, Tipton MJ. Post-exercise cooling techniques in hot, humid conditions. Eur J Appl Physiol. 2009;107(4):385–96. https://doi.org/10.1007/s00421-009-1135-1.

    Article  PubMed  Google Scholar 

  91. Proulx CI, Ducharme MB, Kenny GP. Safe cooling limits from exercise-induced hyperthermia. Eur J Appl Physiol. 2006;96(4):434–45. https://doi.org/10.1007/s00421-005-0063-y.

    Article  CAS  PubMed  Google Scholar 

  92. Taylor NA, Caldwell JN, Van den Heuvel AM, Patterson MJ. To cool, but not too cool: that is the question–immersion cooling for hyperthermia. Med Sci Sports Exerc. 2008;40(11):1962–9. https://doi.org/10.1249/MSS.0b013e31817eee9d.

    Article  PubMed  Google Scholar 

  93. Cheuvront SN, Montain SJ. Myths and methodologies: making sense of exercise mass and water balance. Exp Physiol. 2017;102(9):1047–53. https://doi.org/10.1113/ep086284.

    Article  PubMed  Google Scholar 

  94. Noakes TD, Speedy DB. Case proven: exercise associated hyponatraemia is due to overdrinking. So why did it take 20 years before the original evidence was accepted? Br J Sports Med. 2006;40(7):567–72. https://doi.org/10.1136/bjsm.2005.020354.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  95. Fox RH, Goldsmith R, Kidd DJ, Lewis HE. Acclimatization to heat in man by controlled elevation of body temperature. J Physiol. 1963;166:530–47. https://doi.org/10.1113/jphysiol.1963.sp007121.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  96. Corbett J, Maxwell N, Sunderland C, Gibson O. The BASES expert statement on interventions for improving performance in the heat. The Sport and Exercise Scientist. 2017;53:6–7.

    Google Scholar 

  97. Racinais S, Alonso JM, Coutts AJ, Flouris AD, Girard O, Gonzalez-Alonso J, et al. Consensus recommendations on training and competing in the heat. Br J Sports Med. 2015;49(18):1164–73. https://doi.org/10.1136/bjsports-2015-094915.

    Article  CAS  PubMed  Google Scholar 

  98. Garrett AT, Creasy R, Rehrer NJ, Patterson MJ, Cotter JD. Effectiveness of short-term heat acclimation for highly trained athletes. Eur J Appl Physiol. 2012;112(5):1827–37. https://doi.org/10.1007/s00421-011-2153-3.

    Article  PubMed  Google Scholar 

  99. Rendell RA, Prout J, Costello JT, Massey HC, Tipton MJ, Young JS, et al. Effects of 10 days of separate heat and hypoxic exposure on heat acclimation and temperate exercise performance. Am J Physiol Regul Integr Comp Physiol. 2017;313(3):R191–201. https://doi.org/10.1152/ajpregu.00103.2017.

    Article  PubMed  Google Scholar 

  100. Barwood MJ, Thelwell RC, Tipton MJ. Psychological skills training improves exercise performance in the heat. Med Sci Sports Exerc. 2008;40(2):387–96. https://doi.org/10.1249/mss.0b013e31815adf31.

    Article  PubMed  Google Scholar 

  101. Corbett J, Neal RA, Lunt HC, Tipton MJ. Adaptation to heat and exercise performance under cooler conditions: a new hot topic. Sports Med. 2014;44(10):1323–31. https://doi.org/10.1007/s40279-014-0212-8.

    Article  PubMed  Google Scholar 

  102. Garrett AT, Goosens NG, Rehrer NJ, Patterson MJ, Harrison J, Sammut I, et al. Short-term heat acclimation is effective and may be enhanced rather than impaired by dehydration. Am J Hum Biol. 2014;26(3):311–20. https://doi.org/10.1002/ajhb.22509.

    Article  CAS  PubMed  Google Scholar 

  103. Neal RA, Massey HC, Tipton MJ, Young JS, Corbett J. Effect of permissive dehydration on induction and decay of heat acclimation, and temperate exercise performance. Front Physiol. 2016;7:564. https://doi.org/10.3389/fphys.2016.00564.

    Article  PubMed  PubMed Central  Google Scholar 

  104. van den Heuvel AMJ, Haberley BJ, Hoyle DJR, Croft RJ, Peoples GE, Taylor NAS. Hyperthermia and dehydration: their independent and combined influences on physiological function during rest and exercise. Eur J Appl Physiol. 2020;120(12):2813–34. https://doi.org/10.1007/s00421-020-04493-4.

    Article  PubMed  Google Scholar 

  105. Barwood MJ, Burrows H, Cessford J. North Pole marathon laboratory lessons and field success. Aerosp Med Hum Perform. 2016;87(5):493–7. https://doi.org/10.3357/amhp.4498.2016.

    Article  PubMed  Google Scholar 

  106. Stuempfle KJ, Hoffman MD. Gastrointestinal distress is common during a 161-km ultramarathon. J Sports Sci. 2015;33(17):1814–21. https://doi.org/10.1080/02640414.2015.1012104.

    Article  PubMed  Google Scholar 

  107. Brock-Utne JG, Gaffin SL, Wells MT, Gathiram P, Sohar E, James MF, et al. Endotoxaemia in exhausted runners after a long-distance race. S Afr Med J. 1988;73(9):533–6.

    CAS  PubMed  Google Scholar 

  108. Glace B, Murphy C, McHugh M. Food and fluid intake and disturbances in gastrointestinal and mental function during an ultramarathon. Int J Sport Nutr Exerc Metab. 2002;12(4):414–27. https://doi.org/10.1123/ijsnem.12.4.414.

    Article  PubMed  Google Scholar 

  109. Wardenaar FC, Dijkhuizen R, Ceelen IJ, Jonk E, de Vries JH, Witkamp RF, et al. Nutrient intake by ultramarathon runners: can they meet recommendations? Int J Sport Nutr Exerc Metab. 2015;25(4):375–86. https://doi.org/10.1123/ijsnem.2014-0199.

    Article  CAS  PubMed  Google Scholar 

  110. de Oliveira EP, Burini RC, Jeukendrup A. Gastrointestinal complaints during exercise: prevalence, etiology, and nutritional recommendations. Sports Med. 2014;44(Suppl 1):S79-85. https://doi.org/10.1007/s40279-014-0153-2.

    Article  PubMed  Google Scholar 

  111. Wilson PB. “I think I’m gonna hurl”: a narrative review of the causes of nausea and vomiting in sport. Sports (Basel). 2019. https://doi.org/10.3390/sports7070162.

    Article  PubMed  PubMed Central  Google Scholar 

  112. Stuempfle KJ, Valentino T, Hew-Butler T, Hecht FM, Hoffman MD. Nausea is associated with endotoxemia during a 161-km ultramarathon. J Sports Sci. 2016;34(17):1662–8. https://doi.org/10.1080/02640414.2015.1130238.

    Article  PubMed  Google Scholar 

  113. Hargreaves M, Angus D, Howlett K, Conus NM, Febbraio M. Effect of heat stress on glucose kinetics during exercise. J Appl Physiol (1985). 1996;81(4):1594–7. https://doi.org/10.1152/jappl.1996.81.4.1594.

    Article  CAS  PubMed  Google Scholar 

  114. Montain SJ, Laird JE, Latzka WA, Sawka MN. Aldosterone and vasopressin responses in the heat: hydration level and exercise intensity effects. Med Sci Sports Exerc. 1997;29(5):661–8. https://doi.org/10.1097/00005768-199705000-00012.

    Article  CAS  PubMed  Google Scholar 

  115. Starkie RL, Hargreaves M, Rolland J, Febbraio MA. Heat stress, cytokines, and the immune response to exercise. Brain Behav Immun. 2005;19(5):404–12. https://doi.org/10.1016/j.bbi.2005.03.005.

    Article  CAS  PubMed  Google Scholar 

  116. Snipe RMJ, Khoo A, Kitic CM, Gibson PR, Costa RJS. The impact of exertional-heat stress on gastrointestinal integrity, gastrointestinal symptoms, systemic endotoxin and cytokine profile. Eur J Appl Physiol. 2018;118(2):389–400. https://doi.org/10.1007/s00421-017-3781-z.

    Article  CAS  PubMed  Google Scholar 

  117. van Nieuwenhoven MA, Vriens BE, Brummer RJ, Brouns F. Effect of dehydration on gastrointestinal function at rest and during exercise in humans. Eur J Appl Physiol. 2000;83(6):578–84. https://doi.org/10.1007/s004210000305.

    Article  PubMed  Google Scholar 

  118. Ogden HB, Child RB, Fallowfield JL, Delves SK, Westwood CS, Layden JD. The gastrointestinal exertional heat stroke paradigm: pathophysiology, assessment, severity, aetiology and nutritional countermeasures. Nutrients. 2020. https://doi.org/10.3390/nu12020537.

    Article  PubMed  PubMed Central  Google Scholar 

  119. Wilson PB. Multiple transportable carbohydrates during exercise: current limitations and directions for future research. J Strength Cond Res. 2015;29(7):2056–70. https://doi.org/10.1519/jsc.0000000000000835.

    Article  PubMed  Google Scholar 

  120. Jeukendrup AE. Training the gut for athletes. Sports Med. 2017;47(Suppl 1):101–10. https://doi.org/10.1007/s40279-017-0690-6.

    Article  PubMed  PubMed Central  Google Scholar 

  121. King AJ, Etxebarria N, Ross ML, Garvican-Lewis L, Heikura IA, McKay AKA, et al. Short-term very high carbohydrate diet and gut-training have minor effects on gastrointestinal status and performance in highly trained endurance athletes. Nutrients. 2022. https://doi.org/10.3390/nu14091929.

    Article  PubMed  PubMed Central  Google Scholar 

  122. Viribay A, Arribalzaga S, Mielgo-Ayuso J, Castaneda-Babarro A, Seco-Calvo J, Urdampilleta A. Effects of 120 g/h of carbohydrates intake during a mountain marathon on exercise-induced muscle damage in elite runners. Nutrients. 2020. https://doi.org/10.3390/nu12051367.

    Article  PubMed  PubMed Central  Google Scholar 

  123. Maunder E, Kilding AE, Plews DJ. Substrate metabolism during ironman triathlon: different horses on the same courses. Sports Med. 2018;48(10):2219–26. https://doi.org/10.1007/s40279-018-0938-9.

    Article  PubMed  Google Scholar 

  124. Volek JS, Freidenreich DJ, Saenz C, Kunces LJ, Creighton BC, Bartley JM, et al. Metabolic characteristics of keto-adapted ultra-endurance runners. Metabolism. 2016;65(3):100–10. https://doi.org/10.1016/j.metabol.2015.10.028.

    Article  CAS  PubMed  Google Scholar 

  125. Linderman JK, Laubach LL. Energy balance during 24 hours of treadmill running. J Exer Physiol Online. 2004;7(2):37–44.

    Google Scholar 

  126. Wilson PB. The psychobiological etiology of gastrointestinal distress in sport: a review. J Clin Gastroenterol. 2020;54(4):297–304. https://doi.org/10.1097/mcg.0000000000001308.

    Article  PubMed  Google Scholar 

  127. Gaskell SK, Snipe RMJ, Costa RJS. Test-retest reliability of a modified visual analog scale assessment tool for determining incidence and severity of gastrointestinal symptoms in response to exercise stress. Int J Sport Nutr Exerc Metab. 2019;29(4):411–9. https://doi.org/10.1123/ijsnem.2018-0215.

    Article  PubMed  Google Scholar 

  128. Wilson PB. Frequency of chronic gastrointestinal distress in runners: validity and reliability of a retrospective questionnaire. Int J Sport Nutr Exerc Metab. 2017;27(4):370–6. https://doi.org/10.1123/ijsnem.2016-0305.

    Article  PubMed  Google Scholar 

  129. Stellingwerff T. Competition nutrition practices of elite ultramarathon runners. Int J Sport Nutr Exerc Metab. 2016;26(1):93–9. https://doi.org/10.1123/ijsnem.2015-0030.

    Article  CAS  PubMed  Google Scholar 

  130. Currell K, Jeukendrup AE. Superior endurance performance with ingestion of multiple transportable carbohydrates. Med Sci Sports Exerc. 2008;40(2):275–81. https://doi.org/10.1249/mss.0b013e31815adf19.

    Article  CAS  PubMed  Google Scholar 

  131. Jeukendrup AE, Moseley L. Multiple transportable carbohydrates enhance gastric emptying and fluid delivery. Scand J Med Sci Sports. 2010;20(1):112–21. https://doi.org/10.1111/j.1600-0838.2008.00862.x.

    Article  CAS  PubMed  Google Scholar 

  132. Urdampilleta A, Arribalzaga S, Viribay A, Castaneda-Babarro A, Seco-Calvo J, Mielgo-Ayuso J. Effects of 120 vs. 60 and 90 g/h carbohydrate intake during a trail marathon on neuromuscular function and high intensity run capacity recovery. Nutrients. 2020. https://doi.org/10.3390/nu12072094.

    Article  PubMed  PubMed Central  Google Scholar 

  133. Wilson PB. Ginger (Zingiber officinale) as an analgesic and ergogenic aid in sport: a systemic review. J Strength Cond Res. 2015;29(10):2980–95. https://doi.org/10.1519/jsc.0000000000001098.

    Article  PubMed  Google Scholar 

  134. Burke LM. Re-examining high-fat diets for sports performance: did we call the “Nail in the Coffin” too soon? Sports Med. 2015;45(Suppl 1):S33-49. https://doi.org/10.1007/s40279-015-0393-9.

    Article  PubMed  Google Scholar 

  135. Burke LM, Ross ML, Garvican-Lewis LA, Welvaert M, Heikura IA, Forbes SG, et al. Low carbohydrate, high fat diet impairs exercise economy and negates the performance benefit from intensified training in elite race walkers. J Physiol. 2017;595(9):2785–807. https://doi.org/10.1113/jp273230.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  136. Burke LM. Ketogenic low-CHO, high-fat diet: the future of elite endurance sport? J Physiol. 2021;599(3):819–43. https://doi.org/10.1113/jp278928.

    Article  CAS  PubMed  Google Scholar 

  137. Burke LM, Whitfield J, Heikura IA, Ross MLR, Tee N, Forbes SF, et al. Adaptation to a low carbohydrate high fat diet is rapid but impairs endurance exercise metabolism and performance despite enhanced glycogen availability. J Physiol. 2021;599(3):771–90. https://doi.org/10.1113/jp280221.

    Article  CAS  PubMed  Google Scholar 

  138. Stellingwerff T, Spriet LL, Watt MJ, Kimber NE, Hargreaves M, Hawley JA, et al. Decreased PDH activation and glycogenolysis during exercise following fat adaptation with carbohydrate restoration. Am J Physiol Endocrinol Metab. 2006;290(2):E380–8. https://doi.org/10.1152/ajpendo.00268.2005.

    Article  CAS  PubMed  Google Scholar 

  139. Costa RJS, Hoffman MD, Stellingwerff T. Considerations for ultra-endurance activities: part 1-nutrition. Res Sports Med. 2019;27(2):166–81. https://doi.org/10.1080/15438627.2018.1502188.

    Article  PubMed  Google Scholar 

  140. Best R, McDonald K, Hurst P, Pickering C. Can taste be ergogenic? Eur J Nutr. 2021;60(1):45–54. https://doi.org/10.1007/s00394-020-02274-5.

    Article  PubMed  Google Scholar 

  141. Stuempfle KJ, Hoffman MD, Hew-Butler T. Association of gastrointestinal distress in ultramarathoners with race diet. Int J Sport Nutr Exerc Metab. 2013;23(2):103–9. https://doi.org/10.1123/ijsnem.23.2.103.

    Article  CAS  PubMed  Google Scholar 

  142. Jonvik KL, King M, Rollo I, Stellingwerff T, Pitsiladis Y. New opportunities to advance the field of sports nutrition. Front Sports Act Liv. 2022;4:852230. https://doi.org/10.3389/fspor.2022.852230.

    Article  Google Scholar 

  143. Sutehall S, Muniz-Pardos B, Bosch AN, Galloway SD, Pitsiladis Y. The impact of sodium alginate hydrogel on exogenous glucose oxidation rate and gastrointestinal comfort in well-trained runners. Front Nutr. 2021;8:810041. https://doi.org/10.3389/fnut.2021.810041.

    Article  CAS  PubMed  Google Scholar 

  144. King AJ, Rowe JT, Burke LM. Carbohydrate hydrogel products do not improve performance or gastrointestinal distress during moderate-intensity endurance exercise. Int J Sport Nutr Exerc Metab. 2020;30(5):305–14. https://doi.org/10.1123/ijsnem.2020-0102.

    Article  CAS  PubMed  Google Scholar 

  145. Rowe JT, King R, King AJ, Morrison DJ, Preston T, Wilson OJ, et al. Glucose and fructose hydrogel enhances running performance, exogenous carbohydrate oxidation, and gastrointestinal tolerance. Med Sci Sports Exerc. 2022;54(1):129–40. https://doi.org/10.1249/mss.0000000000002764.

    Article  CAS  PubMed  Google Scholar 

  146. Rynders CA, Morton SJ, Bessesen DH, Wright KP Jr, Broussard JL. Circadian rhythm of substrate oxidation and hormonal regulators of energy balance. Obesity (Silver Spring). 2020;28(Suppl 1):S104–13. https://doi.org/10.1002/oby.22816.

    Article  CAS  PubMed  Google Scholar 

  147. Scheer FA, Morris CJ, Shea SA. The internal circadian clock increases hunger and appetite in the evening independent of food intake and other behaviors. Obesity (Silver Spring). 2013;21(3):421–3. https://doi.org/10.1002/oby.20351.

    Article  PubMed  Google Scholar 

  148. Høeg TB, Olson EM, Skaggs K, Sainani K, Fredericson M, Roche M, et al. Prevalence of female and male athlete triad risk factors in ultramarathon runners. Clin J Sport Med. 2022;32(4):375–81. https://doi.org/10.1097/jsm.0000000000000956.

    Article  PubMed  Google Scholar 

  149. Dickson DN, Wilkinson RL, Noakes TD. Effects of ultra-marathon training and racing on hematologic parameters and serum ferritin levels in well-trained athletes. Int J Sports Med. 1982;03(02):111–7. https://doi.org/10.1055/s-2008-1026073.

    Article  CAS  Google Scholar 

  150. Kaufmann CC, Wegberger C, Tscharre M, Haller PM, Piackova E, Vujasin I, et al. Effect of marathon and ultra-marathon on inflammation and iron homeostasis. Scand J Med Sci Sports. 2021;31(3):542–52. https://doi.org/10.1111/sms.13869.

    Article  PubMed  Google Scholar 

  151. Owens DJ, Allison R, Close GL. Vitamin D and the athlete: current perspectives and new challenges. Sports Med. 2018;48(1):3–16. https://doi.org/10.1007/s40279-017-0841-9.

    Article  PubMed  PubMed Central  Google Scholar 

  152. Mountjoy M, Sundgot-Borgen J, Burke L, Ackerman KE, Blauwet C, Constantini N, et al. International Olympic Committee (IOC) Consensus Statement on relative energy deficiency in sport (RED-S): 2018 Update. Int J Sport Nutr Exerc Metab. 2018;28(4):316–31. https://doi.org/10.1123/ijsnem.2018-0136.

    Article  PubMed  Google Scholar 

  153. Veronese N, Solmi M, Rizza W, Manzato E, Sergi G, Santonastaso P, et al. Vitamin D status in anorexia nervosa: a meta-analysis. Int J Eat Disord. 2015;48(7):803–13. https://doi.org/10.1002/eat.22370.

    Article  PubMed  Google Scholar 

  154. Roebuck GS, Fitzgerald PB, Urquhart DM, Ng SK, Cicuttini FM, Fitzgibbon BM. The psychology of ultra-marathon runners: a systematic review. Psychol Sport Exerc. 2018;37:43–58. https://doi.org/10.1016/j.psychsport.2018.04.004.

    Article  Google Scholar 

  155. Enoka RM, Duchateau J. Translating Fatigue to Human Performance. Med Sci Sports Exerc. 2016;48(11):2228–38. https://doi.org/10.1249/mss.0000000000000929.

    Article  PubMed  PubMed Central  Google Scholar 

  156. Millet GY. Can neuromuscular fatigue explain running strategies and performance in ultra-marathons?: the flush model. Sports Med. 2011;41(6):489–506. https://doi.org/10.2165/11588760-000000000-00000.

    Article  PubMed  Google Scholar 

  157. Hoffman MD, Krouse R. Ultra-obligatory running among ultramarathon runners. Res Sports Med. 2018;26(2):211–21. https://doi.org/10.1080/15438627.2018.1431533.

    Article  PubMed  Google Scholar 

  158. Hanson N, Madaras L, Dicke J, Buckworth J. Motivational differences between half, full and ultramarathoners. J Sport Behav. 2015;38(2):180–91.

    Google Scholar 

  159. Krouse RZ, Ransdell LB, Lucas SM, Pritchard ME. Motivation, goal orientation, coaching, and training habits of women ultrarunners. J Strength Cond Res. 2011;25(10):2835–42. https://doi.org/10.1519/JSC.0b013e318204caa0.

    Article  PubMed  Google Scholar 

  160. Waskiewicz Z, Nikolaidis PT, Chalabaev A, Rosemann T, Knechtle B. Motivation in ultra-marathon runners. Psychol Res Behav Manag. 2019;12:31–7. https://doi.org/10.2147/prbm.S189061.

    Article  PubMed  Google Scholar 

  161. Weich C, Schüler J, Wolff W. 24 hours on the Run— Does boredom matter for ultra-endurance Athletes’ Crises? Int J Environ Res Public Health. 2022;19(11):6859.

    Article  PubMed  PubMed Central  Google Scholar 

  162. Simpson D, Post PG, Young G, Jensen PR. “It’s Not About Taking the Easy Road”: the experiences of ultramarathon runners. Sport Psycholog. 2014;28(2):176–85. https://doi.org/10.1123/tsp.2013-0064.

    Article  Google Scholar 

  163. Acevedo EO, Dzewaltowski DA, Gill DL, Noble JM. Cognitive orientations of ultramarathoners. Sport Psycholog. 1992;6(3):242–52. https://doi.org/10.1123/tsp.6.3.242.

    Article  Google Scholar 

  164. Lane AM, Beedie CJ, Jones MV, Uphill M, Devonport TJ. The BASES expert statement on emotion regulation in sport. J Sports Sci. 2012;30(11):1189–95. https://doi.org/10.1080/02640414.2012.693621.

    Article  PubMed  Google Scholar 

  165. Goddard K, Roberts CM, Anderson L, Woodford L, Byron-Daniel J. Mental toughness and associated personality characteristics of marathon des sables athletes. Front Psychol. 2019;10:2259. https://doi.org/10.3389/fpsyg.2019.02259.

    Article  PubMed  PubMed Central  Google Scholar 

  166. Brace AW, George K, Lovell GP. Mental toughness and self-efficacy of elite ultra-marathon runners. PLoS ONE. 2020;15(11): e0241284. https://doi.org/10.1371/journal.pone.0241284.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  167. Jaeschke A-MC, Sachs ML, Dieffenbach KD. Ultramarathon runners’ perceptions of mental toughness: a qualitative inquiry. Sport Psycholog. 2016;30(3):242–55. https://doi.org/10.1123/tsp.2014-0153.

    Article  Google Scholar 

  168. Christensen DA, Brewer BW, Hutchinson JC. Psychological predictors of performance in a 161 km Ultramarathon Run. Int J Sport Psychol. 2018;49(1):74–90.

    Google Scholar 

  169. Cona G, Cavazzana A, Paoli A, Marcolin G, Grainer A, Bisiacchi PS. It’s a matter of mind! cognitive functioning predicts the athletic performance in ultra-marathon runners. PLoS ONE. 2015;10(7): e0132943. https://doi.org/10.1371/journal.pone.0132943.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  170. Corrion K, Morales V, Bergamaschi A, Massiera B, Morin JB, d’Arripe-Longueville F. Psychosocial factors as predictors of dropout in ultra-trailers. PLoS ONE. 2018;13(11): e0206498. https://doi.org/10.1371/journal.pone.0206498.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  171. Freund W, Weber F, Billich C, Birklein F, Breimhorst M, Schuetz UH. Ultra-marathon runners are different: investigations into pain tolerance and personality traits of participants of the TransEurope FootRace 2009. Pain Pract. 2013;13(7):524–32. https://doi.org/10.1111/papr.12039.

    Article  PubMed  Google Scholar 

  172. Alschuler KN, Kratz AL, Lipman GS, Krabak BJ, Pomeranz D, Burns P, et al. How variability in pain and pain coping relate to pain interference during multistage ultramarathons. Pain. 2019;160(1):257–62. https://doi.org/10.1097/j.pain.0000000000001397.

    Article  PubMed  Google Scholar 

  173. Burgum P, Smith DT. Reduced mood variability is associated with enhanced performance during ultrarunnning. PLoS ONE. 2021;16(9): e0256888. https://doi.org/10.1371/journal.pone.0256888.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  174. Tharion WJ, Strowman SR, Rauch TM. Profile and changes in moods of ultramarathoners. J Sport Exerc Psychol. 1988;10(2):229–35. https://doi.org/10.1123/jsep.10.2.229.

    Article  Google Scholar 

  175. Howe CCF, Pummell E, Pang S, Spendiff O, Moir HJ. Emotional intelligence and mood states impact on the stress response to a treadmill ultramarathon. J Sci Med Sport. 2019;22(7):763–8. https://doi.org/10.1016/j.jsams.2019.02.008.

    Article  PubMed  Google Scholar 

  176. Anglem N, Lucas SJ, Rose EA, Cotter JD. Mood, illness and injury responses and recovery with adventure racing. Wilderness Environ Med. 2008;19(1):30–8. https://doi.org/10.1580/07-weme-or-091.1.

    Article  PubMed  Google Scholar 

  177. Graham SM, Martindale RJJ, McKinley M, Connaboy C, Andronikos G, Susmarski A. The examination of mental toughness, sleep, mood and injury rates in an Arctic ultra-marathon. Eur J Sport Sci. 2021;21(1):100–6. https://doi.org/10.1080/17461391.2020.1733670.

    Article  PubMed  Google Scholar 

  178. Lane AM, Wilson M. Emotions and trait emotional intelligence among ultra-endurance runners. J Sci Med Sport. 2011;14(4):358–62. https://doi.org/10.1016/j.jsams.2011.03.001.

    Article  PubMed  Google Scholar 

  179. Hurdiel R, Peze T, Daugherty J, Girard J, Poussel M, Poletti L, et al. Combined effects of sleep deprivation and strenuous exercise on cognitive performances during The North Face(R) Ultra Trail du Mont Blanc(R) (UTMB(R)). J Sports Sci. 2015;33(7):670–4. https://doi.org/10.1080/02640414.2014.960883.

    Article  PubMed  Google Scholar 

  180. Arnal PJ, Sauvet F, Leger D, van Beers P, Bayon V, Bougard C, et al. Benefits of sleep extension on sustained attention and sleep pressure before and during total sleep deprivation and recovery. Sleep. 2015;38(12):1935–43. https://doi.org/10.5665/sleep.5244.

    Article  PubMed  PubMed Central  Google Scholar 

  181. Jeukendrup AE, Moseley L, Mainwaring GI, Samuels S, Perry S, Mann CH. Exogenous carbohydrate oxidation during ultraendurance exercise. J Appl Physiol (1985). 2006;100(4):1134–41. https://doi.org/10.1152/japplphysiol.00981.2004.

    Article  CAS  PubMed  Google Scholar 

  182. Kerhervé HA, Millet GY, Solomon C. The dynamics of speed selection and psycho-physiological load during a mountain ultramarathon. PLoS ONE. 2015;10(12): e0145482. https://doi.org/10.1371/journal.pone.0145482.

    Article  PubMed  PubMed Central  Google Scholar 

  183. Marcora SM, Staiano W. The limit to exercise tolerance in humans: mind over muscle? Eur J Appl Physiol. 2010;109(4):763–70. https://doi.org/10.1007/s00421-010-1418-6.

    Article  PubMed  Google Scholar 

  184. Marcora SM, Staiano W, Manning V. Mental fatigue impairs physical performance in humans. J Appl Physiol (1985). 2009;106(3):857–64. https://doi.org/10.1152/japplphysiol.91324.2008.

    Article  PubMed  Google Scholar 

  185. Enoka RM, Stuart DG. Neurobiology of muscle fatigue. J Appl Physiol (1985). 1992;72(5):1631–48. https://doi.org/10.1152/jappl.1992.72.5.1631.

    Article  CAS  PubMed  Google Scholar 

  186. Millet GY, Tomazin K, Verges S, Vincent C, Bonnefoy R, Boisson RC, et al. Neuromuscular consequences of an extreme mountain ultra-marathon. PLoS ONE. 2011;6(2): e17059. https://doi.org/10.1371/journal.pone.0017059.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  187. Lollgen H, Graham T, Sjogaard G. Muscle metabolites, force, and perceived exertion bicycling at varying pedal rates. Med Sci Sports Exerc. 1980;12(5):345–51.

    Article  CAS  PubMed  Google Scholar 

  188. Norbury R, Smith SA, Burnley M, Judge M, Mauger AR. The effect of elevated muscle pain on neuromuscular fatigue during exercise. Eur J Appl Physiol. 2022;122(1):113–26. https://doi.org/10.1007/s00421-021-04814-1.

    Article  CAS  PubMed  Google Scholar 

  189. Wuthrich TU, Marty J, Kerherve H, Millet GY, Verges S, Spengler CM. Aspects of respiratory muscle fatigue in a mountain ultramarathon race. Med Sci Sports Exerc. 2015;47(3):519–27. https://doi.org/10.1249/mss.0000000000000449.

    Article  PubMed  Google Scholar 

  190. Romer LM, Polkey MI. Exercise-induced respiratory muscle fatigue: implications for performance. J Appl Physiol (1985). 2008;104(3):879–88. https://doi.org/10.1152/japplphysiol.01157.2007.

    Article  PubMed  Google Scholar 

  191. Marcora SM, Bosio A, de Morree HM. Locomotor muscle fatigue increases cardiorespiratory responses and reduces performance during intense cycling exercise independently from metabolic stress. Am J Physiol Regul Integr Comp Physiol. 2008;294(3):R874–83. https://doi.org/10.1152/ajpregu.00678.2007.

    Article  CAS  PubMed  Google Scholar 

  192. de Morree HM, Marcora SM. Psychobiology of perceived effort during physical tasks. In: Gendolla GHE, Tops M, Koole SL, editors. Handbook of biobehavioral approaches to self-regulation. New York: Springer; 2015. p. 255–70.

    Chapter  Google Scholar 

  193. Lord RN, Utomi V, Oxborough DL, Curry BA, Brown M, George KP. Left ventricular function and mechanics following prolonged endurance exercise: an update and meta-analysis with insights from novel techniques. Eur J Appl Physiol. 2018;118(7):1291–9. https://doi.org/10.1007/s00421-018-3906-z.

    Article  PubMed  PubMed Central  Google Scholar 

  194. Enoka RM, Duchateau J. Inappropriate interpretation of surface EMG signals and muscle fiber characteristics impedes understanding of the control of neuromuscular function. J Appl Physiol. 2015;119(12):1516–8.

    Article  CAS  PubMed  Google Scholar 

  195. Joyner MJ, Baker SE, Senefeld JW, Klassen SA, Wiggins CC. Experiments of nature and within species comparative physiology. Comp Biochem Physiol A Mol Integr Physiol. 2021;253:110864. https://doi.org/10.1016/j.cbpa.2020.110864.

    Article  CAS  PubMed  Google Scholar 

  196. Joyner MJ, Wiggins CC, Baker SE, Klassen SA, Senefeld JW. Exercise and experiments of nature. Compr Physiol. 2023;13(3):4879–907. https://doi.org/10.1002/cphy.c220027.

    Article  PubMed  Google Scholar 

  197. Poole DC, Burnley M, Vanhatalo A, Rossiter HB, Jones AM. Critical power: an important fatigue threshold in exercise physiology. Med Sci Sports Exerc. 2016;48(11):2320.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

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Berger, N.J.A., Best, R., Best, A.W. et al. Limits of Ultra: Towards an Interdisciplinary Understanding of Ultra-Endurance Running Performance. Sports Med 54, 73–93 (2024). https://doi.org/10.1007/s40279-023-01936-8

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