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Scientific reports2022; 12(1); 11528; doi: 10.1038/s41598-022-14274-y

Relationship between Thoroughbred workloads in racing and the fatigue life of equine subchondral bone.

Abstract: Fatigue life (FL) is the number of cycles of load sustained by a material before failure, and is dependent on the load magnitude. For athletes, 'cycles' translates to number of strides, with load proportional to speed. To improve previous investigations estimating workload from distance, we used speed (m/s, x) per stride collected using 5 Hz GPS/800 Hz accelerometer sensors as a proxy for limb load to investigate factors associated with FL in a Thoroughbred race start model over 25,234 race starts, using a combination of mathematical and regression modelling. Fore-limb vertical force (NKg) was estimated using a published equation: Vertical force = 2.778 + 2.1376x - 0.0535x. Joint load (σ) was estimated based on the vertical force, scaled according to the maximum speed and defined experimental loads for the expected variation in load distribution across a joint surface (54-90 MPa). Percentage FL (%FL) was estimated using a published equation for cycles to failure (N) summed across each race start: N = 10 Multivariable mixed-effects linear regression models were generated on %FL, adjusting for horse-level clustering, presented as coefficients; 95%CI. Scaled to the highest joint load, individual starts accrued a mean of 9.34%FL (sd. 1.64). Older age (coef. 0.03; 0.002-0.04), longer race-distances (non-linear power transformed), and firmer track surfaces (ref. Heavy 10: Good 3 coef. 2.37; 2.26-2.48) were associated with greater %FL, and males accrued less than females (p < 0.01). Most variables associated with %FL are reported risk factors for injury. Monitoring strides in racehorses may therefore allow identification of horses at risk, enabling early detection of injury.
Publication Date: 2022-07-07 PubMed ID: 35798766PubMed Central: PMC9262984DOI: 10.1038/s41598-022-14274-yGoogle Scholar: Lookup
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Summary

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This research studied the toll that horse racing takes on thoroughbred horses, specifically, how equine subchondral bone’s fatigue life is affected by intense physical workloads. The authors used in-depth modeling to show that greater horse age, longer race distances, and firmer track surfaces resulted in greater fatigue life, indicating a higher risk of injury. At the same time, female horses showed greater fatigue life than male horses, suggesting they might be more prone to injury.

Speed and Stride as Proxy for Limb Load

  • The researchers used speed per stride to estimate workload, a more specific method than prior studies that only used distance. They collected this data using GPS and accelerometer sensors.
  • The concept of ‘cycles’ was translated to the number of strides a horse takes, with each stride’s load proportional to its speed. This terminology comes from fatigue life (FL), a concept in materials science that refers to the number of load cycles a material can endure before failure.

Modelling Workload and Fatigue Life

  • The workload was calculated using a series of mathematical and regression models developed from over 25,234 race starts. Each variable and mathematical coefficient was carefully selected to correlate with real-world conditions and factors, such as the force exerted by each stride and the distribution of load across a joint surface.
  • The proportion of fatigue life (%FL) was estimated using every stride in each race start. Higher %FL corresponds to higher injury risk in horses. This is a crucial metric in understanding and predicting equine sports injuries.
  • Factors that Influence Fatigue Life

    • They found that older age, longer race-distances, and firmer track surfaces were associated with greater %FL, meaning these factors put thoroughbred horses at a higher risk of injury.
    • Gender also played a role, with male horses showing lower fatigue life loads than females.
    • Most of the variables associated with higher fatigue life are known risk factors for injury in horses.

    Predicting and Preventing Injury

    • The researchers suggest that monitoring strides in racehorses could help identify horses at risk. The information garnered from such monitoring might enable early detection of injury and influence better practices in preparing horses for races, thereby potentially reducing the incidence of fatigue-induced injuries.

Cite This Article

APA
Morrice-West AV, Hitchens PL, Walmsley EA, Tasker K, Lim SL, Smith AD, Whitton RC. (2022). Relationship between Thoroughbred workloads in racing and the fatigue life of equine subchondral bone. Sci Rep, 12(1), 11528. https://doi.org/10.1038/s41598-022-14274-y

Publication

ISSN: 2045-2322
NlmUniqueID: 101563288
Country: England
Language: English
Volume: 12
Issue: 1
Pages: 11528
PII: 11528

Researcher Affiliations

Morrice-West, Ashleigh V
  • Melbourne Veterinary School, Equine Centre, University of Melbourne, 250 Princes Hwy, Werribee, VIC, 3030, Australia. ashleigh.morrice@unimelb.edu.au.
Hitchens, Peta L
  • Melbourne Veterinary School, Equine Centre, University of Melbourne, 250 Princes Hwy, Werribee, VIC, 3030, Australia.
Walmsley, Elizabeth A
  • Melbourne Veterinary School, Equine Centre, University of Melbourne, 250 Princes Hwy, Werribee, VIC, 3030, Australia.
Tasker, Kate
  • Melbourne Veterinary School, Equine Centre, University of Melbourne, 250 Princes Hwy, Werribee, VIC, 3030, Australia.
Lim, Ser Lin
  • Melbourne Veterinary School, Equine Centre, University of Melbourne, 250 Princes Hwy, Werribee, VIC, 3030, Australia.
Smith, Ariel D
  • Melbourne Veterinary School, Equine Centre, University of Melbourne, 250 Princes Hwy, Werribee, VIC, 3030, Australia.
Whitton, R Chris
  • Melbourne Veterinary School, Equine Centre, University of Melbourne, 250 Princes Hwy, Werribee, VIC, 3030, Australia.

MeSH Terms

  • Animals
  • Extremities
  • Fatigue / complications
  • Female
  • Forelimb
  • Horse Diseases
  • Horses
  • Humans
  • Male
  • Physical Conditioning, Animal
  • Risk Factors
  • Workload

Conflict of Interest Statement

The authors declare no competing interests.

References

This article includes 62 references
  1. Cohen ND, Berry SM, Peloso JG, Mundy GD, Howard IC. Association of high-speed exercise with racing injury in thoroughbreds.. J Am Vet Med Assoc 2000 Apr 15;216(8):1273-8.
    doi: 10.2460/javma.2000.216.1273pubmed: 10767969google scholar: lookup
  2. Estberg L. Cumulative racing-speed exercise distance cluster as a risk factor for fatal musculoskeletal injury in Thoroughbred racehorses in California.. Prev. Vet. Med. 1995;24:253–263.
  3. Estberg L, Stover SM, Gardner IA, Drake CM, Johnson B, Ardans A. High-speed exercise history and catastrophic racing fracture in thoroughbreds.. Am J Vet Res 1996 Nov;57(11):1549-55.
    pubmed: 8915427
  4. Estberg L, Gardner IA, Stover SM, Johnson BJ. A case-crossover study of intensive racing and training schedules and risk of catastrophic musculoskeletal injury and lay-up in California thoroughbred racehorses.. Prev Vet Med 1998 Jan;33(1-4):159-70.
    doi: 10.1016/S0167-5877(97)00047-0pubmed: 9500171google scholar: lookup
  5. Hitchens PL, Hill AE, Stover SM. Relationship Between Historical Lameness, Medication Usage, Surgery, and Exercise With Catastrophic Musculoskeletal Injury in Racehorses.. Front Vet Sci 2018;5:217.
    doi: 10.3389/fvets.2018.00217pmc: PMC6137211pubmed: 30246014google scholar: lookup
  6. Hitchens PL, Morrice-West AV, Stevenson MA, Whitton RC. Meta-analysis of risk factors for racehorse catastrophic musculoskeletal injury in flat racing.. Vet J 2019 Mar;245:29-40.
    pubmed: 30819423doi: 10.1016/j.tvjl.2018.11.014google scholar: lookup
  7. Reed SR, Jackson BF, Wood JL, Price JS, Verheyen KL. Exercise affects joint injury risk in young Thoroughbreds in training.. Vet J 2013 Jun;196(3):339-44.
    doi: 10.1016/j.tvjl.2012.11.014pubmed: 23265863google scholar: lookup
  8. Verheyen K, Price J, Lanyon L, Wood J. Exercise distance and speed affect the risk of fracture in racehorses.. Bone 2006 Dec;39(6):1322-30.
    doi: 10.1016/j.bone.2006.05.025pubmed: 16926125google scholar: lookup
  9. Rogers CW, Firth EC. Musculoskeletal responses of 2-year-old Thoroughbred horses to early training. 2. Measurement error and effect of training stage on the relationship between objective and subjective criteria of training workload.. N Z Vet J 2004 Oct;52(5):272-9.
    doi: 10.1080/00480169.2004.36439pubmed: 15768123google scholar: lookup
  10. Rogers CW. Describing workload and scientific information on conditioning horses.. Equine Comparat. Exercise Physiol. 2007;4:1–6.
    doi: 10.1017/S1478061507727408google scholar: lookup
  11. Stares J, Dawson B, Peeling P, Heasman J, Rogalski B, Drew M, Colby M, Dupont G, Lester L. Identifying high risk loading conditions for in-season injury in elite Australian football players.. J Sci Med Sport 2018 Jan;21(1):46-51.
    doi: 10.1016/j.jsams.2017.05.012pubmed: 28601588google scholar: lookup
  12. Cummins C, Welch M, Inkster B, Cupples B, Weaving D, Jones B, King D, Murphy A. Modelling the relationships between volume, intensity and injury-risk in professional rugby league players.. J Sci Med Sport 2019 Jun;22(6):653-660.
    doi: 10.1016/j.jsams.2018.11.028pubmed: 30651223google scholar: lookup
  13. Bazzano M, Giudice E, Rizzo M, Congiu F, Zumbo A, Arfuso F, Di Pietro S, Bruschetta D, Piccione G. Application of a combined global positioning and heart rate monitoring system in jumper horses during an official competition - A preliminary study.. Acta Vet Hung 2016 Jun;64(2):189-200.
    doi: 10.1556/004.2016.019pubmed: 27342090google scholar: lookup
  14. Fonseca RG, Kenny DA, Hill EW, Katz LM. The association of various speed indices to training responses in Thoroughbred flat racehorses measured with a global positioning and heart rate monitoring system.. Equine Vet J Suppl 2010 Nov;(38):51-7.
  15. Vermeulen AD, Evans DL. Measurements of fitness in thoroughbred racehorses using field studies of heart rate and velocity with a global positioning system.. Equine Vet J Suppl 2006 Aug;(36):113-7.
  16. Kingston JK, Soppet GM, Rogers CW, Firth EC. Use of a global positioning and heart rate monitoring system to assess training load in a group of thoroughbred racehorses.. Equine Vet J Suppl 2006 Aug;(36):106-9.
  17. Martig S, Chen W, Lee PV, Whitton RC. Bone fatigue and its implications for injuries in racehorses.. Equine Vet J 2014 Jul;46(4):408-15.
    doi: 10.1111/evj.12241pubmed: 24528139google scholar: lookup
  18. Muir P, Peterson AL, Sample SJ, Scollay MC, Markel MD, Kalscheur VL. Exercise-induced metacarpophalangeal joint adaptation in the Thoroughbred racehorse.. J Anat 2008 Dec;213(6):706-17.
  19. Cui W. A state-of-the-art review on fatigue life prediction methods for metal structures.. J. Mar. Sci. Technol. 2002;7:43–56.
    doi: 10.1007/s007730200012google scholar: lookup
  20. Carter DR, Hayes WC. Compact bone fatigue damage--I. Residual strength and stiffness.. J Biomech 1977;10(5-6):325-37.
    doi: 10.1016/0021-9290(77)90005-7pubmed: 893471google scholar: lookup
  21. Salkind, M. in Composite Materials: Testing and Design (Second Conference) 333–364 (ASTM International, 1972).
  22. Martig S, Lee PV, Anderson GA, Whitton RC. Compressive fatigue life of subchondral bone of the metacarpal condyle in thoroughbred racehorses.. Bone 2013 Dec;57(2):392-8.
    doi: 10.1016/j.bone.2013.09.006pubmed: 24063945google scholar: lookup
  23. Carter DR, Caler WE, Spengler DM, Frankel VH. Uniaxial fatigue of human cortical bone. The influence of tissue physical characteristics.. J Biomech 1981;14(7):461-70.
    doi: 10.1016/0021-9290(81)90096-8pubmed: 7276007google scholar: lookup
  24. Dendorfer S, Maier HJ, Taylor D, Hammer J. Anisotropy of the fatigue behaviour of cancellous bone.. J Biomech 2008;41(3):636-41.
  25. Witte TH, Hirst CV, Wilson AM. Effect of speed on stride parameters in racehorses at gallop in field conditions.. J Exp Biol 2006 Nov;209(Pt 21):4389-97.
    doi: 10.1242/jeb.02518pubmed: 17050854google scholar: lookup
  26. Parkin TD, Clegg PD, French NP, Proudman CJ, Riggs CM, Singer ER, Webbon PM, Morgan KL. Catastrophic fracture of the lateral condyle of the third metacarpus/metatarsus in UK racehorses - fracture descriptions and pre-existing pathology.. Vet J 2006 Jan;171(1):157-65.
    doi: 10.1016/j.tvjl.2004.10.009pubmed: 16427592google scholar: lookup
  27. Bailey CJ, Reid SW, Hodgson DR, Rose RJ. Impact of injuries and disease on a cohort of two- and three-year-old thoroughbreds in training.. Vet Rec 1999 Oct 23;145(17):487-93.
    doi: 10.1136/vr.145.17.487pubmed: 10596871google scholar: lookup
  28. Barr ED, Pinchbeck GL, Clegg PD, Boyde A, Riggs CM. Post mortem evaluation of palmar osteochondral disease (traumatic osteochondrosis) of the metacarpo/metatarsophalangeal joint in Thoroughbred racehorses.. Equine Vet J 2009 Apr;41(4):366-71.
    doi: 10.2746/042516409X368372pubmed: 19562898google scholar: lookup
  29. Harrison SM, Whitton RC, Kawcak CE, Stover SM, Pandy MG. Relationship between muscle forces, joint loading and utilization of elastic strain energy in equine locomotion.. J Exp Biol 2010 Dec 1;213(Pt 23):3998-4009.
    doi: 10.1242/jeb.044545pubmed: 21075941google scholar: lookup
  30. Morrice-West AV, Hitchens PL, Walmsley EA, Stevenson MA, Wong ASM, Whitton RC. Variation in GPS and accelerometer recorded velocity and stride parameters of galloping Thoroughbred horses.. Equine Vet J 2021 Sep;53(5):1063-1074.
    doi: 10.1111/evj.13370pubmed: 33098592google scholar: lookup
  31. Rubio-Martínez LM, Cruz AM, Gordon K, Hurtig MB. Mechanical properties of subchondral bone in the distal aspect of third metacarpal bones from Thoroughbred racehorses.. Am J Vet Res 2008 Nov;69(11):1423-33.
    doi: 10.2460/ajvr.69.11.1423pubmed: 18980424google scholar: lookup
  32. Harrison SM, Whitton RC, Kawcak CE, Stover SM, Pandy MG. Evaluation of a subject-specific finite-element model of the equine metacarpophalangeal joint under physiological load.. J Biomech 2014 Jan 3;47(1):65-73.
  33. Baum CF. Stata tip 63: Modeling proportions.. Stata J. 2008;8:299–303.
  34. Royston, P. BOXTID: Stata module to fit Box-Tidwell and exponential regression models (2013).
  35. Shaktivesh S, Malekipour F, Whitton RC, Hitchens PL, Lee PV. Fatigue behavior of subchondral bone under simulated physiological loads of equine athletic training.. J Mech Behav Biomed Mater 2020 Oct;110:103920.
    doi: 10.1016/j.jmbbm.2020.103920pubmed: 32957215google scholar: lookup
  36. Ratzlaff M, Shindell R, White K. The interrelationships of stride lengths and stride times to velocites of galloping horses.. J. Equine Vet. Sci. 1985;5:279–283.
  37. Seder JA, Vickery CE. Temporal and kinematic gait variables of Thoroughbred Racehorses at or near racing speeds.. J. Equine Vet. Sci. 2003;23:S82–S112.
  38. Parkes RSV, Weller R, Pfau T, Witte TH. The Effect of Training on Stride Duration in a Cohort of Two-Year-Old and Three-Year-Old Thoroughbred Racehorses.. Animals (Basel) 2019 Jul 22;9(7).
    doi: 10.3390/ani9070466pmc: PMC6680649pubmed: 31336595google scholar: lookup
  39. Ferrari M, Pfau T, Wilson AM, Weller R. The effect of training on stride parameters in a cohort of National Hunt racing Thoroughbreds: a preliminary study.. Equine Vet J 2009 May;41(5):493-7.
    doi: 10.2746/042516409X374591pubmed: 19642411google scholar: lookup
  40. Takahashi T. The effect of age on the racing speed of Thoroughbred racehorses.. J Equine Sci 2015;26(2):43-8.
    doi: 10.1294/jes.26.43pmc: PMC4496421pubmed: 26170760google scholar: lookup
  41. Oki H, Willham RL, Sasaki Y. Genetics of racing performance in the Japanese Thoroughbred horse:: I. Description of the data.. J Anim Breed Genet 1994 Jan 12;111(1-6):121-7.
  42. Martin GS, Strand E, Kearney MT. Use of statistical models to evaluate racing performance in thoroughbreds.. J Am Vet Med Assoc 1996 Dec 1;209(11):1900-6.
    pubmed: 8944806
  43. Spence AJ, Thurman AS, Maher MJ, Wilson AM. Speed, pacing strategy and aerodynamic drafting in Thoroughbred horse racing.. Biol Lett 2012 Aug 23;8(4):678-81.
    doi: 10.1098/rsbl.2011.1120pmc: PMC3391435pubmed: 22399784google scholar: lookup
  44. Boden LA, Anderson GA, Charles JA, Morgan KL, Morton JM, Parkin TD, Clarke AF, Slocombe RF. Risk factors for Thoroughbred racehorse fatality in flat starts in Victoria, Australia (1989-2004).. Equine Vet J 2007 Sep;39(5):430-7.
    pubmed: 17910268doi: 10.2746/042516407x183162google scholar: lookup
  45. Bailey CJ, Reid SW, Hodgson DR, Bourke JM, Rose RJ. Flat, hurdle and steeple racing: risk factors for musculoskeletal injury.. Equine Vet J 1998 Nov;30(6):498-503.
  46. Williams RB, Harkins LS, Hammond CJ, Wood JL. Racehorse injuries, clinical problems and fatalities recorded on British racecourses from flat racing and National Hunt racing during 1996, 1997 and 1998.. Equine Vet J 2001 Sep;33(5):478-86.
    doi: 10.2746/042516401776254808pubmed: 11558743google scholar: lookup
  47. Kristoffersen M, Parkin TD, Singer ER. Catastrophic biaxial proximal sesamoid bone fractures in UK Thoroughbred races (1999-2004): horse characteristics and racing history.. Equine Vet J 2010 Jul;42(5):420-4.
  48. Reardon RJ, Boden L, Stirk AJ, Parkin TD. Accuracy of distal limb fracture diagnosis at British racecourses 1999-2005.. Vet Rec 2014 May 10;174(19):477.
    doi: 10.1136/vr.102053pubmed: 24570402google scholar: lookup
  49. Parkin TD, Clegg PD, French NP, Proudman CJ, Riggs CM, Singer ER, Webbon PM, Morgan KL. Catastrophic fracture of the lateral condyle of the third metacarpus/metatarsus in UK racehorses - fracture descriptions and pre-existing pathology.. Vet J 2006 Jan;171(1):157-65.
    doi: 10.1016/j.tvjl.2004.10.009pubmed: 16427592google scholar: lookup
  50. Parkin TD, Clegg PD, French NP, Proudman CJ, Riggs CM, Singer ER, Webbon PM, Morgan KL. Risk of fatal distal limb fractures among Thoroughbreds involved in the five types of racing in the United Kingdom.. Vet Rec 2004 Apr 17;154(16):493-7.
    doi: 10.1136/vr.154.16.493pubmed: 15130054google scholar: lookup
  51. Georgopoulos SP, Parkin TD. Risk factors for equine fractures in Thoroughbred flat racing in North America.. Prev Vet Med 2017 Apr 1;139(Pt B):99-104.
  52. Bailey CJ, Reid SW, Hodgson DR, Suann CJ, Rose RJ. Risk factors associated with musculoskeletal injuries in Australian thoroughbred racehorses.. Prev Vet Med 1997 Sep;32(1-2):47-55.
    doi: 10.1016/S0167-5877(97)00009-3pubmed: 9361320google scholar: lookup
  53. Bolwell C, Rogers C, Gee E, McIlwraith W. Epidemiology of Musculoskeletal Injury during Racing on New Zealand Racetracks 2005-2011.. Animals (Basel) 2017 Aug 11;7(8).
    doi: 10.3390/ani7080062pmc: PMC5575574pubmed: 28800064google scholar: lookup
  54. Allen SE, Rosanowski SM, Stirk AJ, Verheyen KLP. Description of veterinary events and risk factors for fatality in National Hunt flat racing Thoroughbreds in Great Britain (2000-2013).. Equine Vet J 2017 Nov;49(6):700-705.
    doi: 10.1111/evj.12676pubmed: 28235142google scholar: lookup
  55. Cohen ND, Peloso JG, Mundy GD, Fisher M, Holland RE, Little TV, Misheff MM, Watkins JP, Honnas CM, Moyer W. Racing-related factors and results of prerace physical inspection and their association with musculoskeletal injuries incurred in thoroughbreds during races.. J Am Vet Med Assoc 1997 Aug 15;211(4):454-63.
    pubmed: 9267508
  56. Cohen ND, Mundy GD, Peloso JG, Carey VJ, Amend NK. Results of physical inspection before races and race-related characteristics and their association with musculoskeletal injuries in Thoroughbreds during races.. J Am Vet Med Assoc 1999 Sep 1;215(5):654-61.
    pubmed: 10476712
  57. Henley WE, Rogers K, Harkins L, Wood JL. A comparison of survival models for assessing risk of racehorse fatality.. Prev Vet Med 2006 Apr 17;74(1):3-20.
  58. Hernandez J, Hawkins DL, Scollay MC. Race-start characteristics and risk of catastrophic musculoskeletal injury in Thoroughbred racehorses.. J Am Vet Med Assoc 2001 Jan 1;218(1):83-6.
    doi: 10.2460/javma.2001.218.83pubmed: 11149721google scholar: lookup
  59. Parkin TD, Clegg PD, French NP, Proudman CJ, Riggs CM, Singer ER, Webbon PM, Morgan KL. Horse-level risk factors for fatal distal limb fracture in racing Thoroughbreds in the UK.. Equine Vet J 2004 Sep;36(6):513-9.
    doi: 10.2746/0425164044877387pubmed: 15460076google scholar: lookup
  60. Parkin TD, Clegg PD, French NP, Proudman CJ, Riggs CM, Singer ER, Webbon PM, Morgan KL. Risk factors for fatal lateral condylar fracture of the third metacarpus/metatarsus in UK racing.. Equine Vet J 2005 May;37(3):192-9.
    doi: 10.2746/0425164054530641pubmed: 15892225google scholar: lookup
  61. Schubert AG, Kempf J, Heiderscheit BC. Influence of stride frequency and length on running mechanics: a systematic review.. Sports Health 2014 May;6(3):210-7.
    doi: 10.1177/1941738113508544pmc: PMC4000471pubmed: 24790690google scholar: lookup
  62. Witte TH, Knill K, Wilson AM. Determination of peak vertical ground reaction force from duty factor in the horse (Equus caballus).. J Exp Biol 2004 Oct;207(Pt 21):3639-48.
    doi: 10.1242/jeb.01182pubmed: 15371472google scholar: lookup

Citations

This article has been cited 1 times.
  1. Bennet ED, Parkin TDH. Anomalous Incidence of Fatal Musculoskeletal Injury in North American 2-Year-Old Thoroughbred Racehorses in the Year 2020.. Animals (Basel) 2023 Aug 9;13(16).
    doi: 10.3390/ani13162572pubmed: 37627362google scholar: lookup