title: Days-lost to training and competition in relation to workload in 263 elite show-jumping horses in four European countries.
abstract: Orthopaedic, or other, injuries in sports medicine can be quantified using the 'days-lost to training' concept. Both the training regimen and the surface used in training and racing can affect the health of racehorses. Our aim was to associate 'days-lost to training' in elite-level show-jumpers to horse characteristics, training and management strategies, and the time spent working on various training and competition surfaces. We designed a longitudinal study of professional riders in four European countries. Data were recorded using training diaries. Reasons for days-lost were classified into non-acute and acute orthopaedic, medical, hoof-related, and undefined. We produced descriptive statistics of training durations, relative to type of training, surfaces used, and days-lost. We created zero-inflated negative-binomial random-effects models using the overall days-lost as outcome. In the whole dataset, duration variables related to training surfaces were analysed as independent. The Swedish data only were also used to test whether duration variables were related to competition surfaces. Thirty-one riders with 263 horses provided data on 39,028 days at risk. Of these, 2357 (6.0%) were days-lost (55% and 22% of these were due to non-acute and acute orthopaedic injuries, respectively) in 126 horses. In the all-country model, controlling for season, a significant variable was country. Switzerland and the UK had lower incidence-rate ratios (IR) compared to Sweden (IRs 0.2 and 0.03, respectively). Horses with previous orthopaedic problems had almost a doubled IR (1.8) of days-lost due to orthopaedic injury, compared to baseline. If the horse had jumping training more than 1 min per day at risk the IRs were 6.9-7 (compared to less than this amount of time); this was, however, likely an effect of a small baseline. Variation in training was a protective factor with a dose-response relationship; the category with the highest variation had an IR of 0.1. In the Swedish model, controlling for season, there was an association of year (IR 2.8 year 2010). Further, if the horse rested >17-25% of the days at risk, or >33% of the DAR2, had IRs 3.5 and 3.0, compared to less time. Horses ≥ 6 years had IRs of 1.8-2.0, compared to younger horses. Limited training use of sand surface was a risk-factor (IR 2.2; >4 ≤ 12 min/day at risk), compared to not training on sand. Training/competing on sand-wood was a protective factor (IRs 0.4-0.5) compared to not using this surface.
authors.affiliation: Department of Clinical Sciences, Faculty of Veterinary Medicine and Animal Husbandry, Swedish University of Agricultural Sciences, Box 7054, SE-750 07 Uppsala, Sweden. Electronic address: Agneta.Egenvall@slu.se.
authors.forename: A
authors.initials: A
authors.lastname: Egenvall
authors.forename: C A
authors.initials: CA
authors.lastname: Tranquille
authors.forename: A C
authors.initials: AC
authors.lastname: Lönnell
authors.forename: C
authors.initials: C
authors.lastname: Bitschnau
authors.forename: A
authors.initials: A
authors.lastname: Oomen
authors.forename: E
authors.initials: E
authors.lastname: Hernlund
authors.forename: S
authors.initials: S
authors.lastname: Montavon
authors.forename: M A
authors.initials: MA
authors.lastname: Franko
authors.forename: R C
authors.initials: RC
authors.lastname: Murray
authors.forename: M A
authors.initials: MA
authors.lastname: Weishaupt
authors.forename: van R
authors.initials: vR
authors.lastname: Weeren
authors.forename: L
authors.initials: L
authors.lastname: Roepstorff
mesh_terms: D000367:Age Factors; D000822:Animal Husbandry; D000818:Animals; D005060:Europe / Q000453:epidemiology; D005260:Female; D015775:Fractures, Stress / Q000453:epidemiology / Q000209:etiology / Q000503:physiopathology / Q000662:veterinary; D006734:Horse Diseases / Q000453:epidemiology / Q000209:etiology / Q000503:physiopathology*; D006736:Horses / Q000293:injuries / Q000502:physiology; D015994:Incidence; D007794:Lameness, Animal / Q000453:epidemiology / Q000209:etiology / Q000503:physiopathology; D008137:Longitudinal Studies; D008297:Male; D008954:Models, Biological; D009140:Musculoskeletal Diseases / Q000453:epidemiology / Q000209:etiology / Q000503:physiopathology / Q000662:veterinary; D009141:Musculoskeletal System / Q000293:injuries; D010805:Physical Conditioning, Animal; D011446:Prospective Studies; D013997:Time Factors
keywords: Days-lost; Equine; Show jumping; Surface; Zero-inflated negative-binomial model