SummaryThe primary objective is the description of bone mineral density (BMD) and body composition in newly licensed jockeys. One in three male, flat jockeys has a very low bone mineral density. Further research is needed to assess the short-term risk of fractures and long-term health implications of these findings.IntroductionDescribe bone mineral density (BMD) and body composition in entry-level male and female, flat and jump jockeys in Great Britain.MethodsData was collected on jockeys applying for a professional jockey license between 2013 and 2015. Areal BMD at the spine, femoral neck (FN), total hip and body composition were assessed by dual-energy X-ray absorptiometry (DXA) scan. We examined differences between BMD and body composition by gender and race type (flat or jump). Volumetric bone mineral apparent density (BMAD) of the spine and FN was also calculated to account for group differences in bone size.ResultsSeventy-nine male flat jockeys (age 18.5 ± 1.9, BMI 19.0 ± 1.4), 69 male jump (age 20.7 ± 2.0, BMI 20.6 ± 1.3) and 37 female flat jockeys (age 19.3 ± 2.0, BMI 20.8 ± 1.7) took part in this study. Spine BMD Z-scores ≤−2 for male flat, male jump and female flat jockeys were 29, 13 and 2.7%, respectively. Spine BMD was lower in male than female flat jockeys (p<0.001). All BMD scores were lower in male flat compared to male jump jockeys (p<0.001). Body fat percent (BF %) was lower in male flat jockeys compared to male jump and female flat jockeys (p<0.05). Lean mass index (LMI) was lower in male flat compared to male jump jockeys (p<0.001).ConclusionsMale flat jockeys had a significantly lower BMD, LMI and BF% compared to jump jockeys and female flat jockeys. Male flat jockeys had lower spine BMD scores than females. Individual bone maturation may influence these findings. Further investigation into the relevance of low BMD and altered body composition on jockey health is required.Electronic supplementary materialThe online version of this article (doi:10.1007/s00198-017-4086-0) contains supplementary material, which is available to authorized users.

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5To test the hypothesis that daily weight-making is more problematic to health in male 6 compared with female jockeys, we compared the bone-density and resting metabolic 7 rate (RMR) in weight-matched male and female Flat-jockeys. RMR (kcal.kg -1 lean 8 mass) was lower in males compared with females as well as lower bone-density Z-9 scores at the hip and lumbar spine. Data suggest the lifestyle of male jockeys' 10 compromise health more severely than females, possibly due to making-weight more 11 frequently.

Objectives: Equestrian helmets are designed to pass certification standards based on linear drop tests onto rigid steel surfaces. However, concussions in equestrian sports occur most commonly when a rider is thrown off a horse and obliquely impacts a compliant surface such as turf or sand. This paper seeks to elucidate the mechanics of such impacts and thereby propose corresponding thresholds for the occurrence of concussion that can improve equestrian helmet standards and designs. Design: The present study examined the biomechanics of real-world equestrian accidents and developed thresholds for the occurrence of concussive injury. Methods: Twenty-five concussive and 25 non-concussive falls in equestrian sports were reconstructed using a combination of video analysis, computational and physical reconstruction methods. These represented male and female accidents from horse racing and the crosscountry phase of eventing. Results: The resulting thresholds for concussion [59 g, 2700 rad/s 2 , 28 rad/s, 0.24 (MPS), 6.6 kPa and 0.27 (CSMD 10) for 50% risk] were consistent with those reported in the literature and represent a unique combination of head kinematic thresholds compared to other sports. Current equestrian helmet standards commonly use a threshold of 250 g and a linear drop to a steel anvil resulting in less than 15 ms impacts. This investigation found that concussive equestrian accidents occurred from oblique impacts to turf or sand with lower magnitude and longer duration impacts (<130 g and >20 ms). This suggests that current equestrian helmet standards may not adequately represent real-world concussive impact conditions and, consequently, there is an urgent need to assess the protective capacity of equestrian helmets under real-world conditions.

The Berlin statement on sport-related concussion was published in 2017 using evidence-based recommendations. We aimed to examine (1) the implementation of, distribution and education based on the Berlin recommendations, and the development of sport-specific protocols/guidelines among professional and elite sports, (2) the implementation of guidelines at the community level, (3) translation of guidelines into different languages, and (4) research activities. Senior medical advisers and chief medical officers from Australian Football League, All Japan Judo Federation, British Horseracing Authority, Cricket Australia, Fédération Equestre Internationale, Football Association, Gaelic Athletic Association, International Boxing Association, Irish Horseracing Regulatory Board, Major League Baseball, National Football League, National Hockey League, National Rugby League, and World Rugby completed a questionnaire. The results demonstrated that all 14 sporting organizations have published concussion protocols/guidelines based on the Berlin recommendations, including Recognize, Removal from play, Re-evaluation, Rest, Recovery, and Return to play. There is variable inclusion of Prolonged symptoms. Prevention and Risk reduction and Long-term effects are addressed in the guidelines, rules and regulations, and/or sport-specific research. There is variability in education programs, monitoring compliance with guidelines, and publication in other languages. All sporting bodies are actively involved in concussion research. We conclude that the Berlin recommendations have been included in concussion protocols/guidelines by all the sporting bodies, with consistency in the essential components of the recommendations, whilst also allowing for sport- and regional-specific variations. Education at the elite, community, and junior levels remains an ongoing challenge, and future iterations of guidelines may consider multiple language versions, and community- and junior-level guidelines.