Abstract
A skeletal design which favours running and walking, including the greatest ratio of leg length to body weight of any mammal; the ability to sweat and so to exercise vigorously in the heat; and greater endurance than all land mammals other than the Alaskan Husky, indicates that humans evolved as endurance animals. The development of tools to accurately measure time and distance in the nineteenth century inspired some humans to define the limits of this special capacity. Beginning with Six-Day Professional Pedestrian Races in London and New York in the 1880s, followed a decade later by Six-Day Professional Cycling Races – the immediate precursor of the first six-day Tour de France Cycliste race in 1903, which itself inspired the 1928 and 1929 4,960 km “Bunion Derbies” between Los Angeles and New York across the breadth of the United States of America – established those unique sporting events that continue to challenge the modern limits of human endurance.
But an analysis of the total energy expenditure achieved by athletes competing in those events establishes that none approaches those reached by another group – the explorers of the heroic age of polar exploration in the early twentieth century. Thus the greatest recorded human endurance performances occurred during the Antarctic sledding expeditions led by Robert Scott in 1911/12 and Ernest Shackleton in 1914/16.By man-hauling sleds for 10 hours daily for approximately 159 and 160 consecutive days respectively, members of those expeditions would have expended close to a total of 1,000,000 kcal. By comparison completing a Six-Day Pedestrian event (55,000 kcal) or the Tour de France (168,000 kcal), or cycling (180,000 kcal) or running (340,000 kcal) across America, requires a considerably smaller total energy expenditure.
Thus the limits of human endurance were set at the start of the twentieth century and have not recently been approached. Given good health and an adequate food supply to prevent starvation and scurvy, these limits are set by the mind, not by the body. For it is the mind that determines who chooses to start and who best stays the distance.
Similar content being viewed by others
References
Berry H (1990) From LA to New York, from New York to L.AH, Berry, Chorley
Bramble DM, Lieberman DE (2004) Endurance running and the evolution of Homo. Nature 432:345–352
Cherry-Garrard A (1989) The worst journey in the world. Carroll and Graf, New York
Foster C, Foster D (2005) Speaking with earth and sky. David Phillips Publishers, Cape Town
Gonzalez-Alonso J, Teller C, Andersen SL et al. (1999) Influence of body temperature on the development of fatigue during prolonged exercise in the heat. J Appl Physiol 86:1032–1039
Gordon B, Baker JC (1929) Observations on the apparent adaptability of the body to infections, unusual hardships, changing environment and prolonged strenuous exertion. Am J Med Sci 178:1–8
Heacox K (1999) Shackleton: The Antarctic Challenge. National Geographic, Washington, DC
Heinrich B (2001) Racing the antelope. Harper Collins Publishers Inc., New York
Hill AV (1925) The physiological basis of athletic records. Lancet 2:481–486
Huntford R (1981) The last place on earth. Pan Books Ltd, London
Jeukendrup AE (2002) High Performance Cycling. In: Jeukendrup AE (ed) Human Kinetics Publishers, Champaign
Kenney WL, DeGroot DW, Holowatz LA (2004) Extremes of human heat tolerance: Life at the precipice of thermoregulatory failure. Journal of Thermal Biology 29:479–485
Knechtle B, Enggist A, Jehle T (2005) Energy turnover at the Race Across AMerica (RAAM) – a case report. Int.J Sports Med 26:499–503
Messner R (1979) Everest: Expedition to the Ultimate. Kaye and Ward, London
Nevill AM, Whyte G (2005) Are there limits to running world records? Med Sci Sports Exerc 37:1785–1788
Noakes TD (2003) Lore of running. Human Kinetics Publishers, Champaign, IL
Noakes TD (2004) Tainted glory–doping and athletic performance. N Engl J Med 351:847–849
Noakes TD, St Clair Gibson A (2004) Logical limitations to the “catastrophe” models of fatigue during exercise in humans. Br J Sports Med 38:648–649
Rontoyannis GP, Skoulis T, Pavlou KN (1989) Energy balance in ultramarathon running. Am J Clin Nutr 49:976–979
Saris WH, Erp-Baart MA, Brouns F et al. (1989) Study on food intake and energy expenditure during extreme sustained exercise: the Tour de France. Int J Sports Med 10 (Suppl 1):S26–S31
Shackleton E (1999) South: journals of his last expedition to Antarctica. Konecky and Knoecky, Old Saybrook, CT
Shackleton E (1999) The heart of the Antarctic. Carroll and Graf Publishers Inc., New York, NY
Solomon S (2001) The coldest march. Yale University Press, New Haven
St Clair Gibson A, Noakes TD (2004) Evidence for complex system integration and dynamic neural regulation of skeletal muscle recruitment during exercise in humans. Br J Sports Med 38:797–806
Stroud M (1986) Scott: 75 years on. Br Med J (Clin Res Ed) 293:1652–1653
Stroud M (1998) The nutritional demands of very prolonged exercise in man. Proc Nutr Soc 57:55–61
Stroud MA (1987) Nutrition and energy balance on the ‘Footsteps of Scott’ expedition 1984–86. Hum Nutr Appl Nutr 41:426–433
Stroud MA, Coward WA, Sawyer MB (1993) Measurements of energy expenditure using isotope-labelled water (2H2(18)O) during an Arctic expedition. Eur J Appl Physiol Occup. Physiol 67:375–379
Stroud MA, Jackson AA, Waterlow JC (1996) Protein turnover rates of two human subjects during an unassisted crossing of Antarctica. Br J Nutr 76:165–174
Stroud MA, Ritz P, Coward WA et al. (1997) Energy expenditure using isotope- labelled water (2H218O), exercise performance, skeletal muscle enzyme activities and plasma biochemical parameters in humans during 95 days of endurance exercise with inadequate energy intake. Eur J Appl Physiol Occup Physiol 76:243–252
Tucker R, Marle T, Lambert EV et al. (2006) The rate of heat storage mediates an anticipatory reduction in exercise intensity during cycling at a fixed rating of perceived exertion. J Physiol (Epub ahead of print)
Tucker R, Rauch L, Harley YX et al. (2004) Impaired exercise performance in the heat is associated with an anticipatory reduction in skeletal muscle recruitment. Pflugers Arch 448:422–430
Woodland L (2003) The crooked path to victory.Cycle Publishing, San Francisco
Author information
Authors and Affiliations
Corresponding author
Additional information
Based on a paper presented as the pre-dinner speech at the Cardiology at the Limits Conference, Cape Town, April 1, 2006
Rights and permissions
About this article
Cite this article
Noakes, T.D. The limits of endurance exercise. Basic Res Cardiol 101, 408–417 (2006). https://doi.org/10.1007/s00395-006-0607-2
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00395-006-0607-2