Analyze Diet
Comprehensive Physiology2011; 1(1); 1-37; doi: 10.1002/cphy.c091001

Highly athletic terrestrial mammals: horses and dogs.

Abstract: Evolutionary forces drive beneficial adaptations in response to a complex array of environmental conditions. In contrast, over several millennia, humans have been so enamored by the running/athletic prowess of horses and dogs that they have sculpted their anatomy and physiology based solely upon running speed. Thus, through hundreds of generations, those structural and functional traits crucial for running fast have been optimized. Central among these traits is the capacity to uptake, transport and utilize oxygen at spectacular rates. Moreover, the coupling of the key systems--pulmonary-cardiovascular-muscular is so exquisitely tuned in horses and dogs that oxygen uptake response kinetics evidence little inertia as the animal transitions from rest to exercise. These fast oxygen uptake kinetics minimize Intramyocyte perturbations that can limit exercise tolerance. For the physiologist, study of horses and dogs allows investigation not only of a broader range of oxidative function than available in humans, but explores the very limits of mammalian biological adaptability. Specifically, the unparalleled equine cardiovascular and muscular systems can transport and utilize more oxygen than the lungs can supply. Two consequences of this situation, particularly in the horse, are profound exercise-induced arterial hypoxemia and hypercapnia as well as structural failure of the delicate blood-gas barrier causing pulmonary hemorrhage and, in the extreme, overt epistaxis. This chapter compares and contrasts horses and dogs with humans with respect to the structural and functional features that enable these extraordinary mammals to support their prodigious oxidative and therefore athletic capabilities.
Publication Date: 2011-01-01 PubMed ID: 23737162DOI: 10.1002/cphy.c091001Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
  • Comparative Study
  • Journal Article
  • Research Support
  • N.I.H.
  • Extramural
  • Research Support
  • Non-U.S. Gov't
  • Review

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research article investigates how continuous human intervention over many generations has supremely tailored the structure and function of dogs and horses for athletic prowess. The paper dives into the extraordinary aerobic capacities of these animals and the physiological consequences of such adaptations.

Optimized Athletic Traits in Horses and Dogs

  • The article explores how human intervention over millennia has led to the selection and enhancement of traits in dogs and horses that are beneficial for running and athletics.
  • Structural and functional traits, especially those associated with the rapid uptake, transport and utilization of oxygen, have been honed over hundreds of generations, making these animals highly athletic and efficient runners.
  • The animals’ pulmonary-cardiovascular-muscular system in particular is highly optimized, allowing an almost seamless transition from rest to exercise without significant disruptions in oxygen uptake kinetics.

Unique Physiological Features and Consequences

  • The research highlights unique features of the cardiovascular-muscular systems in horses that allow them to transport and utilize more oxygen than their lungs can supply.
  • Such a capability results in two significant physiological phenomena in horses: profound exercise-induced arterial hypoxemia and hypercapnia, and structural failure of the delicate blood-gas barrier, which can lead to pulmonary hemorrhage and, in extreme cases, overt epistaxis.
  • Studying these features and their implications not only provides insights into mammalian adaptability but also opens up exciting avenues for examining the extent of oxidative function as compared to humans.

Comparative study with humans

  • While shedding light on the extraordinary physiological adaptations of dogs and horses, the paper also contrasts these with human capabilities.
  • Understanding the structural and functional aspects that empower the extraordinary athletic capabilities of these animals also offers a perspective on humans’ athletic capacities and limitations.

Cite This Article

APA
Poole DC, Erickson HH. (2011). Highly athletic terrestrial mammals: horses and dogs. Compr Physiol, 1(1), 1-37. https://doi.org/10.1002/cphy.c091001

Publication

ISSN: 2040-4603
NlmUniqueID: 101574442
Country: United States
Language: English
Volume: 1
Issue: 1
Pages: 1-37

Researcher Affiliations

Poole, David C
  • Departments of Kinesiology, Anatomy and Physiology, Kansas State University, Manhattan, KS, USA. poole@vet.ksu.edu
Erickson, Howard H

    MeSH Terms

    • Animals
    • Cardiovascular System / anatomy & histology
    • Dogs / anatomy & histology
    • Dogs / physiology
    • Exercise Test
    • Hemorrhage / etiology
    • Hemorrhage / veterinary
    • Horse Diseases / etiology
    • Horses / anatomy & histology
    • Horses / physiology
    • Humans
    • Locomotion / physiology
    • Lung Diseases / etiology
    • Lung Diseases / veterinary
    • Oxygen Consumption / physiology
    • Physical Conditioning, Animal / adverse effects
    • Respiratory System / anatomy & histology
    • Running / physiology
    • Species Specificity

    Grant Funding

    • 17731 / PHS HHS
    • HL-50306 / NHLBI NIH HHS

    Citations

    This article has been cited 40 times.
    1. Takahashi K, Mukai K, Takahashi Y, Ebisuda Y, Sugiyama F, Hatta H, Kitaoka Y. Effects of hypoxia and hyperoxia on exercise-induced metabolomic and transcriptomic profiles in equine skeletal muscle. J Exp Biol 2025 Dec 15;228(24).
      doi: 10.1242/jeb.250956pubmed: 41199666google scholar: lookup
    2. Bozzola C, Sala G, Stancari G, Ferrucci F, Zucca E. Comparison Between Tracheal Wash and Bronchoalveolar Lavage Cytology for the Assessment of Airway Inflammation in Racehorses Affected by Exercise-Induced Pulmonary Hemorrhage. Animals (Basel) 2025 Sep 5;15(17).
      doi: 10.3390/ani15172609pubmed: 40941404google scholar: lookup
    3. Maffi S, Bonometti A, Chiaffredo C, Galimberti A, Barletta C, Morselli K, Menchetti L, Quattrone A. Assessment of Body Condition in Long-Distance Sled Dogs: Validation of the Body Condition Score and Its Association with Ultrasonographic, Plicometric, and Anthropometric Measurements. Vet Sci 2025 Aug 16;12(8).
      doi: 10.3390/vetsci12080766pubmed: 40872716google scholar: lookup
    4. Coker MS, Ravelli MN, Shriver TC, Schoeller DA, Slivka DR, Ruby BC, Coker RH. Sex-specific energy expenditure during the Alaska mountain wilderness ski classic; insights from an Arctic winter expedition. Front Physiol 2025;16:1543834.
      doi: 10.3389/fphys.2025.1543834pubmed: 40365085google scholar: lookup
    5. Muir WW, Yiew XT, Bateman SW, Hahn RG. Volume kinetics of lactated Ringer's solution in adult horses. Equine Vet J 2026 Jan;58(1):220-229.
      doi: 10.1111/evj.14534pubmed: 40357908google scholar: lookup
    6. Heinonen I. Cardiac output limits maximal oxygen consumption, but what limits maximal cardiac output?. Exp Physiol 2025 May;110(5):666-674.
      doi: 10.1113/EP091594pubmed: 40193294google scholar: lookup
    7. Castiglione GM, Chen X, Xu Z, Dbouk NH, Bose AA, Carmona-Berrio D, Chi EE, Zhou L, Boronina TN, Cole RN, Wu S, Liu AD, Liu TD, Lu H, Kalbfleisch T, Rinker D, Rokas A, Ortved K, Duh EJ. Running a genetic stop sign accelerates oxygen metabolism and energy production in horses. Science 2025 Mar 28;387(6741):eadr8589.
      doi: 10.1126/science.adr8589pubmed: 40146832google scholar: lookup
    8. Vasseur M, Lepers R, Langevin N, Julliand S, Grimm P. Fibrolytic efficiency of the large intestine microbiota may benefit running speed in French trotters: A pilot study. Physiol Rep 2024 Nov;12(21):e70110.
      doi: 10.14814/phy2.70110pubmed: 39533164google scholar: lookup
    9. Takahashi K, Mukai K, Ebisuda Y, Sugiyama F, Yoshida T, Hatta H, Kitaoka Y. Effects of pacing strategy on metabolic responses to 2-min intense exercise in Thoroughbred horses. Sci Rep 2024 Aug 7;14(1):18352.
      doi: 10.1038/s41598-024-69339-xpubmed: 39112781google scholar: lookup
    10. Schumacher A, Gehlen H. Health of Polo Horses. Animals (Basel) 2024 Jun 8;14(12).
      doi: 10.3390/ani14121735pubmed: 38929354google scholar: lookup
    11. Rigaut C, Giaprakis A, Deruyver L, Goole J, Lambert P, Haut B. The air conditioning in the nose of mammals depends on their mass and on their maximal running speed. Sci Rep 2024 Apr 20;14(1):9053.
      doi: 10.1038/s41598-024-59768-zpubmed: 38643255google scholar: lookup
    12. Martin A, Lepers R, Vasseur M, Julliand S. Effect of high-starch or high-fibre diets on the energy metabolism and physical performance of horses during an 8-week training period. Front Physiol 2023;14:1213032.
      doi: 10.3389/fphys.2023.1213032pubmed: 37745248google scholar: lookup
    13. Peters CM, Dempsey JA, Hopkins SR, Sheel AW. Is the Lung Built for Exercise? Advances and Unresolved Questions. Med Sci Sports Exerc 2023 Dec 1;55(12):2143-2159.
      doi: 10.1249/MSS.0000000000003255pubmed: 37443459google scholar: lookup
    14. Ramsook AH, Dominelli PB, Angus SA, Senefeld JW, Wiggins CC, Joyner MJ. The oxygen transport cascade and exercise: Lessons from comparative physiology. Comp Biochem Physiol A Mol Integr Physiol 2023 Aug;282:111442.
      doi: 10.1016/j.cbpa.2023.111442pubmed: 37182787google scholar: lookup
    15. Gołyński M, Metyk M, Ciszewska J, Szczepanik MP, Fitch G, Bęczkowski PM. Homocysteine-Potential Novel Diagnostic Indicator of Health and Disease in Horses. Animals (Basel) 2023 Apr 11;13(8).
      doi: 10.3390/ani13081311pubmed: 37106874google scholar: lookup
    16. Brownlow M, Mizzi JX. An Overview of Exertional Heat Illness in Thoroughbred Racehorses: Pathophysiology, Diagnosis, and Treatment Rationale. Animals (Basel) 2023 Feb 9;13(4).
      doi: 10.3390/ani13040610pubmed: 36830397google scholar: lookup
    17. Lo Feudo CM, Stucchi L, Conturba B, Stancari G, Ferrucci F. Impact of Lower Airway Inflammation on Fitness Parameters in Standardbred Racehorses. Animals (Basel) 2022 Nov 21;12(22).
      doi: 10.3390/ani12223228pubmed: 36428455google scholar: lookup
    18. Poole DC, Musch TI, Colburn TD. Oxygen flux from capillary to mitochondria: integration of contemporary discoveries. Eur J Appl Physiol 2022 Jan;122(1):7-28.
      doi: 10.1007/s00421-021-04854-7pubmed: 34940908google scholar: lookup
    19. Hopster K, Hurcombe SDA. Agreement of Bioreactance Cardiac Output Monitoring With Thermodilution in Healthy Standing Horses. Front Vet Sci 2021;8:701339.
      doi: 10.3389/fvets.2021.701339pubmed: 34414227google scholar: lookup
    20. Tosi I, Art T, Boemer F, Votion DM, Davis MS. Acylcarnitine profile in Alaskan sled dogs during submaximal multiday exercise points out metabolic flexibility and liver role in energy metabolism. PLoS One 2021;16(8):e0256009.
      doi: 10.1371/journal.pone.0256009pubmed: 34383825google scholar: lookup
    21. Dempsey JA, La Gerche A, Hull JH. Is the healthy respiratory system built just right, overbuilt, or underbuilt to meet the demands imposed by exercise?. J Appl Physiol (1985) 2020 Dec 1;129(6):1235-1256.
    22. Cruces P, Retamal J, Hurtado DE, Erranz B, Iturrieta P, González C, Díaz F. A physiological approach to understand the role of respiratory effort in the progression of lung injury in SARS-CoV-2 infection. Crit Care 2020 Aug 10;24(1):494.
      doi: 10.1186/s13054-020-03197-7pubmed: 32778136google scholar: lookup
    23. Templeman JR, McCarthy N, Lindinger MI, Shoveller AK. Changes in salivary electrolyte concentrations in mid-distance trained sled dogs during 12 weeks of incremental conditioning. Physiol Rep 2020 Jun;8(12):e14493.
      doi: 10.14814/phy2.14493pubmed: 32596999google scholar: lookup
    24. Poole DC, Copp SW, Colburn TD, Craig JC, Allen DL, Sturek M, O'Leary DS, Zucker IH, Musch TI. Guidelines for animal exercise and training protocols for cardiovascular studies. Am J Physiol Heart Circ Physiol 2020 May 1;318(5):H1100-H1138.
      doi: 10.1152/ajpheart.00697.2019pubmed: 32196357google scholar: lookup
    25. Poole DC, Behnke BJ, Musch TI. The role of vascular function on exercise capacity in health and disease. J Physiol 2021 Feb;599(3):889-910.
      doi: 10.1113/JP278931pubmed: 31977068google scholar: lookup
    26. Blott S, Cunningham H, Malkowski L, Brown A, Rauch C. A Mechanogenetic Model of Exercise-Induced Pulmonary Haemorrhage in the Thoroughbred Horse. Genes (Basel) 2019 Nov 1;10(11).
      doi: 10.3390/genes10110880pubmed: 31683933google scholar: lookup
    27. Cercone M, Olsen E, Perkins JD, Cheetham J, Mitchell LM, Ducharme NG. Investigation into pathophysiology of naturally occurring palatal instability and intermittent dorsal displacement of the soft palate (DDSP) in racehorses: Thyro-hyoid muscles fatigue during exercise. PLoS One 2019;14(10):e0224524.
      doi: 10.1371/journal.pone.0224524pubmed: 31652282google scholar: lookup
    28. Vera L, Campos Arias D, Muylle S, Stergiopulos N, Segers P, van Loon G. A 1D computer model of the arterial circulation in horses: An important resource for studying global interactions between heart and vessels under normal and pathological conditions. PLoS One 2019;14(8):e0221425.
      doi: 10.1371/journal.pone.0221425pubmed: 31433827google scholar: lookup
    29. Fogarty MJ, Sieck GC. Evolution and Functional Differentiation of the Diaphragm Muscle of Mammals. Compr Physiol 2019 Mar 14;9(2):715-766.
      doi: 10.1002/cphy.c180012pubmed: 30873594google scholar: lookup
    30. Cercone M, Hokanson CM, Olsen E, Ducharme NG, Mitchell LM, Piercy RJ, Cheetham J. Asymmetric recurrent laryngeal nerve conduction velocities and dorsal cricoarytenoid muscle electromyographic characteristics in clinically normal horses. Sci Rep 2019 Feb 25;9(1):2713.
      doi: 10.1038/s41598-019-39189-zpubmed: 30804428google scholar: lookup
    31. Poole DC, Erickson HH. Exercise-induced pulmonary hemorrhage: where are we now?. Vet Med (Auckl) 2016;7:133-148.
      doi: 10.2147/VMRR.S120421pubmed: 30050846google scholar: lookup
    32. Vellers HL, Kleeberger SR, Lightfoot JT. Inter-individual variation in adaptations to endurance and resistance exercise training: genetic approaches towards understanding a complex phenotype. Mamm Genome 2018 Feb;29(1-2):48-62.
      doi: 10.1007/s00335-017-9732-5pubmed: 29356897google scholar: lookup
    33. Marck A, Antero J, Berthelot G, Saulière G, Jancovici JM, Masson-Delmotte V, Boeuf G, Spedding M, Le Bourg É, Toussaint JF. Are We Reaching the Limits of Homo sapiens?. Front Physiol 2017;8:812.
      doi: 10.3389/fphys.2017.00812pubmed: 29123486google scholar: lookup
    34. Shave R, Howatson G, Dickson D, Young L. Exercise-Induced Cardiac Remodeling: Lessons from Humans, Horses, and Dogs. Vet Sci 2017 Feb 12;4(1).
      doi: 10.3390/vetsci4010009pubmed: 29056668google scholar: lookup
    35. Bryce CM, Wilmers CC, Williams TM. Energetics and evasion dynamics of large predators and prey: pumas vs. hounds. PeerJ 2017;5:e3701.
      doi: 10.7717/peerj.3701pubmed: 28828280google scholar: lookup
    36. Miller B, Hamilton K, Boushel R, Williamson K, Laner V, Gnaiger E, Davis M. Mitochondrial respiration in highly aerobic canines in the non-raced state and after a 1600-km sled dog race. PLoS One 2017;12(4):e0174874.
      doi: 10.1371/journal.pone.0174874pubmed: 28445477google scholar: lookup
    37. Guseh JS. The Evolving Landscape of Exercise-Induced Pulmonary Hypertension. Curr Treat Options Cardiovasc Med 2016 Jun;18(6):41.
      doi: 10.1007/s11936-016-0459-5pubmed: 27174296google scholar: lookup
    38. Joyner MJ, Casey DP. Regulation of increased blood flow (hyperemia) to muscles during exercise: a hierarchy of competing physiological needs. Physiol Rev 2015 Apr;95(2):549-601.
      doi: 10.1152/physrev.00035.2013pubmed: 25834232google scholar: lookup
    39. Miller BF, Ehrlicher SE, Drake JC, Peelor FF 3rd, Biela LM, Pratt-Phillips S, Davis M, Hamilton KL. Assessment of protein synthesis in highly aerobic canine species at the onset and during exercise training. J Appl Physiol (1985) 2015 Apr 1;118(7):811-7.
    40. Calbet JA, Lundby C. Skeletal muscle vasodilatation during maximal exercise in health and disease. J Physiol 2012 Dec 15;590(24):6285-96.
      doi: 10.1113/jphysiol.2012.241190pubmed: 23027820google scholar: lookup