Browsing by Author "Cochrane DJ"

Now showing 1 - 4 of 4
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    A threshold model to determine the association between race rides and fall risk for early career (apprentice) jockeys.
    (Elsevier B.V., 2024-10-31) Legg KA; Cochrane DJ; Gee EK; Rogers CW
    Objectives To identify descriptors associated with success in apprentice jockeys and to determine optimum numbers of jockeys for safer race riding. Design Retrospective cohort study. Methods Incidence-rates for jockey falls and success (wins per 1,000 race-starts), time and number of races spent at different apprentice levels were calculated for 807 apprentice and professional jockeys over 19 years of Thoroughbred flat racing in New Zealand (n = 524,551 race-starts). Survival analysis was used to compare career progression for jockeys that fell and those that did not, and individual seasonal fall incidence-rates were modelled. Results Apprentices had the highest fall incidence-rate in their first year of race riding (2.4, interquartile range 1.7–3.2 vs 1.1, interquartile range 1.0–1.2, p < 0.05) and a lower success incidence-rate compared to non-apprentice jockeys (71, interquartile range 67–75 vs 97 interquartile range 96–98, p < 0.05). Jockeys who fell during their apprenticeship rode in more race rides to progress towards professional status than those who did not. There was an inverse power relationship between fall incidence-rate and race rides per season for jockeys, with the inflection point at 33 rides per season. Half (48 %) of the jockeys rode fewer than 33 rides per season. Conclusions There is a surplus number of jockeys, riding at high fall risk, produced than is required by the number of race riding opportunities. Greater investment into the fitness, education and selection of a smaller cohort of dedicated apprentices, may be beneficial to reduce the risk of early career fall or injury in jockeys and requires further investigation.
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    Effect of Resonant Frequency Vibration on Delayed Onset Muscle Soreness and Resulting Stiffness as Measured by Shear-Wave Elastography.
    (MDPI (Basel, Switzerland), 2021-07-24) Jones GC; Blotter JD; Smallwood CD; Eggett DL; Cochrane DJ; Feland JB; Marino J; Scudiero O
    This study utilized resonant frequency vibration to the upper body to determine changes in pain, stiffness and isometric strength of the biceps brachii after eccentric damage. Thirty-one participants without recent resistance training were randomized into three groups: a Control (C) group and two eccentric exercise groups (No vibration (NV) and Vibration (V)). After muscle damage, participants in the V group received upper body vibration (UBV) therapy for 5 min on days 1-4. All participants completed a visual analog scale (VAS), maximum voluntary isometric contraction (MVIC), and shear wave elastography (SWE) of the bicep at baseline (pre-exercise), 24 h, 48 h, and 1-week post exercise. There was a significant difference between V and NV at 24 h for VAS (p = 0.0051), at 24 h and 1-week for MVIC (p = 0.0017 and p = 0.0016, respectively). There was a significant decrease in SWE for the V group from 24-48 h (p = 0.0003), while there was no significant change in the NV group (p = 0.9341). The use of UBV resonant vibration decreased MVIC decrement and reduced VAS pain ratings at 24 h post eccentric damage. SWE was strongly negatively correlated with MVIC and may function as a predictor of intrinsic muscle state in the time course of recovery of the biceps brachii.
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    Physical Fitness of Thoroughbred Horse Racing Jockeys
    (Springer Nature, 2023-10-30) Legg KA; Cochrane DJ; Gee EK; Chin YY; Rogers CW
    Purpose Thoroughbred racing jockeys compete at maximum physiological capacity in a sport with a high risk of falls and injury. A greater understanding of the physical capacities determining jockey performance may lead to minimum physical performance parameters and corrective interventions to improve jockey fitness and performance and reduce jockey and horse injury. The aim of this study was to develop appropriate physical testing procedures for jockeys and a physical fitness profile for different licence levels. Methods Fifty-eight jockeys (n = 24 females, n = 34 males), representing all apprentice jockeys licenced in New Zealand in 2021 (100%, n = 8 probationers and n = 39 apprentices) and eleven professional jockeys (14%) were assessed to determine baseline physiological and fitness data. Descriptive statistics and boxplots were used to compare aerobic fitness, abdominal (core), upper and lower body strength, muscular power, reaction time, flexibility and a novel ‘saddle’ test targeting lower body strength, balance, and endurance between licencing levels. Effect Size (ES) was used to determine magnitude of differences between groups. Results More experienced jockeys had greater relative lower body strength (ES = 0.2–0.7) and better balance (ES = 0.5–0.9) compared to the less experienced groups. Jockeys who were in the top 20 of the premiership table (jockey rankings) had faster reaction times (ES = 0.7) and greater core extensor strength (ES = 0.7) than other cohorts. Most tests showed little differentiation between jockey licence levels, however the ‘saddle test’ showed greater variability in the less experienced race riders. This test may be an effective measure of jockey baseline performance. Conclusions These data could be used to inform minimum jockey licencing requirements and future physical fitness training programmes to increase jockey physiological fitness, thereby minimising risk of falls or injury due to physiological deficits and performance.
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    Relationship between experience and head kinematics in race riding jockeys
    (Springer Nature Limited, London, 2025-04-26) Legg KA; Cochrane DJ; Gee EK; Chin Y-Y; Rogers CW
    Thoroughbred race-riding requires jockeys to attenuate horse movement and maintain postural stability whilst galloping at high speeds. This study aimed to investigate the head movement of jockeys in relation to race-riding experience. Accelerometer and heart rate data were collected from twelve apprentice and two senior jockeys during 85 exercise rides and 82 trial rides. Mean head displacements were determined for each jockey by double integrating the filtered acceleration data. A mixed effect multivariable linear regression model was used to investigate the relationship between jockey experience, physiological variables and head kinematics. The median (IQR) head displacement was higher for exercise riding (0.12 m, 0.09–0.14 m) than trial riding (0.06 m, 0.05–0.09 m). Jockey head displacement decreased with increasing speed of the horse (p < 0.001) and greater jockey experience (p = 0.007). Higher exercise load had a greater effect on head displacement with less experienced jockey’s (p = 0.02). The effect of speed was lower for trial riding than exercise riding (p < 0.001). More experienced jockeys had a greater ability to attenuate horse oscillation than inexperienced jockeys. This ability became more pronounced at higher exercise loads, reflecting a higher level of physical fitness and riding skill level. Measurement of jockey head displacement may provide a simple measure of assessing jockey race-riding ability or fitness.