title: Modern riding style improves horse racing times.
abstract: When animals carry loads, there is a proportionate increase in metabolic cost, and in humans this increase in cost is reduced when the load is elastically coupled to the load bearer. Major horse race times and records improved by 5 to 7% around 1900 when jockeys adopted a crouched posture. We show that jockeys move to isolate themselves from the movement of their mount. This would be difficult or impossible with a seated or upright, straight-legged posture. This isolation means that the horse supports the jockey's body weight but does not have to move the jockey through each cyclical stride path. This posture requires substantial work by jockeys, who have near-maximum heart rates during racing.
authors.affiliation: Structure and Motion Laboratory, Royal Veterinary College, University of London, Hatfield, AL9 7TA UK.
authors.forename: Thilo
authors.initials: T
authors.lastname: Pfau
authors.forename: Andrew
authors.initials: A
authors.lastname: Spence
authors.forename: Sandra
authors.initials: S
authors.lastname: Starke
authors.forename: Marta
authors.initials: M
authors.lastname: Ferrari
authors.forename: Alan
authors.initials: A
authors.lastname: Wilson
mesh_terms: D000054:Acceleration; D000818:Animals; D001696:Biomechanical Phenomena; D001835:Body Weight; D004734:Energy Metabolism; D006736:Horses / Q000502:physiology*; D006801:Humans; D008124:Locomotion; D009068:Movement; D010805:Physical Conditioning, Animal; D011187:Posture; D013177:Sports / Q000502:physiology*; D016474:Weight-Bearing