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Objectives: To investigate the association between air jacket usage and rider injury severity in equestrian eventing competition falls world-wide., Design: Retrospective data analysis., Methods: An analysis was conducted on Fédération Equestre Internationale data for 1819 riders who fell wearing an air jacket and 1486 riders who fell while not wearing an air jacket from 2015 to 2017. Injury data were categorised as either 'no/slight injury' or 'serious/fatal injury'. A chi-square test determined whether an association was present between injury severity category and air jacket usage and binary logistic regression determined the effect size of this association., Results: As a result of falls, 3203 riders sustained no/slight injuries and 102 sustained serious/fatal injuries. While 55.0% of riders who fell were wearing an air jacket, they represented 67.6% of the serious/fatal injury outcomes. Air jacket usage was significantly associated with serious/fatal injuries in falls (X² = 6.76; p = 0.009). Riders wearing an air jacket had 1.7 times (95%CI 1.14-2.64) increased odds of sustaining a serious or fatal injury in a fall compared to riders not wearing an air jacket., Conclusions: Riders wearing an air jacket were over represented in the percentage of serious or fatal injuries in falls compared to riders who only wore a standard body protector. Further research is needed to understand the reason(s) for this finding. It is recommended that additional data on injury outcomes, rider characteristics and the biomechanics of falls be examined in future analyses, and that air jacket and body protector characteristics be further investigated., (Copyright © 2019 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)

The techniques of spin bowling in cricket have been largely formulated from the collective intuitions of past players. A standard model of bowling technique has been generally prescribed for both off-spin and leg-spin bowlers, but there has been no biomechanics research to validate this approach. This study measured 20 Type-2 off-spin and 15 Type-2 leg-spin bowlers using a 3D Cortex motion analysis system. Correlation coefficients between segmental kinematic variables and spin rate in the off-spin and leg-spin bowlers revealed that off-spin bowling was associated with an earlier movement time of the thorax, whereas leg-spin bowling was associated with a greater magnitude and earlier movement time of pelvis rotation, as well as a greater magnitude of pelvis-shoulder separation movement. The maximum velocity of rear hip flexion differentiated between both groups of bowlers. The GLM suggested that for off-spinners, rear hip flexion velocity significantly explained the variance in spin rate (subject to sequential timing constraints), while for leg-spinners, the time of maximum rear hip flexion and maximum arm circumduction velocity significantly explained variance in spin rate. This study supports the notion that off-spinners and leg-spinners have significant differences in their joint kinematics, and should not be coached under a one-size-fits-all technical model.

Spin bowling is generally coached using a standard technical framework, but this practice has not been based upon a comparative biomechanical analysis of leg-spin and off-spin bowling. This study analysed the three-dimensional (3D) kinematics of 23 off-spin and 20 leg-spin bowlers using a Cortex motion analysis system to identify how aspects of the respective techniques differed. A multivariate ANOVA found that certain data tended to validate some of the stated differences in the coaching literature. Off-spin bowlers had a significantly shorter stride length (p = 0.006) and spin rate (p = 0.001), but a greater release height than leg-spinners (p = 0.007). In addition, a number of other kinematic differences were identified that were not previously documented in coaching literature. These included a larger rear knee flexion (p = 0.007), faster approach speed (p < 0.001), and flexing elbow action during the arm acceleration compared with an extension action used by most of the off-spin bowlers. Off-spin and leg-spin bowlers also deviated from the standard coaching model for the shoulder alignment, front knee angle at release, and forearm mechanics. This study suggests that off-spin and leg-spin are distinct bowling techniques, supporting the development of two different coaching models in spin bowling.

The objectives of this study were to profile the physiological and physical characteristics of elite dragon boat paddlers, to identify characteristics that predict race performance and to quantify the metabolic energy contributions to simulated 200-m and 500-m dragon boat racing. Eleven, national level, male, Japanese dragon boat paddlers completed a battery of tests on a paddling ergometer including an incremental maximal aerobic capacity test, a 2-minute maximal accumulated oxygen deficit (MAOD) test, and simulated 200-m and 500-m races. A physiological and physical profile of subjects was compiled. Results showed that 200-m race performance correlated with flexed arm girth and excess postexercise oxygen consumption (EPOC) measured in the 30 minutes after the MAOD test, whereas 500-m race performance correlated with body fat percentage, relaxed and flexed arm girth, MAOD, EPOC, and peak power during the MAOD test. Stepwise multiple regression revealed that flexed arm girth was the most powerful predictor of 200-m and 500-m race performance, followed by EPOC with the combination of these 2 factors able to explain 74% and 68% of the variance in 200-m and 500-m race performance, respectively. Aerobic energy contributions for 200-m (50 seconds) and 500-m (1 minute 50 seconds) races were (mean (95% confidence intervals)) 52.1% (range, 47.4-56.8%) and 67.5% (range, 60.1-77.8%), respectively. In conclusion, coaches should develop training programs targeted at developing upper-body musculature and increasing anaerobic capacity because these factors are the strongest predictors of 200-m and 500-m race performance. Given the substantial aerobic energy contributions even for a 200-m race event, coaches should aim to increase the maximal aerobic capacity of the paddler in preparation for both 200-m and 500-m events.

Males typically have greater upper body strength than do females, which is likely to impact on the rowing techniques adopted by each sex. The aim of this study was to quantify energy contributions and compare the joint power production of upper extremity joints between the sexes. Seven males and eight females performed 60 s trials at five different stroke rates. External forces were measured at the handle and stretcher, while kinematics were recorded by motion analysis. Joint moments were derived by inverse dynamic calculations, followed by the calculation of joint powers and gross mechanical energy expenditure. Male rowers expended more total external energy per stroke and made a larger percentage contribution of angular shoulder energy to their total external energy expenditure. As stroke rate increased, the contribution from elbow and angular shoulder energy contributions decreased for both males and females. Female rowers decreased their angular shoulder contribution at a slower rate than did males as stroke rate increased. The overall percentage of work done on the stretcher was higher for male rowers, and this difference further increased at higher stroke rates. The results of this study suggest that specific upper body conditioning may be particularly important for female rowers.

This preliminary study aimed to quantify the magnitude of the peak shoulder distraction force during the bowling action of female cricket fast bowlers. An eight camera Vicon motion analysis system operating at 120 Hz recorded the fast bowling actions of 18 Australian female fast bowlers. A three segment inverse solution model of the bowling arm was used to calculate the shoulder distraction force. A large peak shoulder distraction force was recorded during the early stages of the follow-through of the bowling action. When normalized for body weight, the distraction force was within the range of values reported for baseball and softball pitchers, who are considered to be at high risk of shoulder injury. Therefore, the relative importance of the peak shoulder distraction force in the fast bowling action for the development of shoulder pain in female cricket fast bowlers warrants further investigation.

The effect of anthropometric differences in shank to thigh length ratio upon timing and magnitude of joint power production during the drive phase of the rowing stroke was investigated in 14 elite male rowers. Rowers were tested on the RowPerfect ergometer which was instrumented at the handle and foot stretcher to measure force generation, and a nine segment inverse dynamics model used to calculate the rower's joint and overall power production. Rowers were divided into two groups according to relative shank thigh ratio. Time to half lumbar power generation was significantly earlier in shorter shank rowers (p = 0.028) compared to longer shank rowers, who showed no lumbar power generation during the same period of the drive phase. Rowers with a relatively shorter shank demonstrated earlier lumbar power generation during the drive phase resulting from restricted rotation of the pelvic segment requiring increased lumbar extension in these rowers. Earlier lumbar power generation and extension did not appear to directly affect performance measures of the short shank group, and so can be attributed to a technical adaptation developed to maximise rowing performance.

This pilot study aimed to determine the magnitude of ground reaction forces experienced by female cricket fast bowlers at front foot contact in the delivery stride of the bowling action. The peak vertical force, peak horizontal braking force and vertical loading rate were assessed in 15 elite Australian female fast bowlers. A sequential averaging procedure indicated that a mean of twelve trials (+/-2.8) were required to achieve performance stability across these ground reaction force variables and this demonstrated the importance of analyzing a sufficient number of trials to obtain representative data. The mean peak vertical ground reaction force was 3.49kN (+/-0.81) and the mean peak horizontal braking force was 2.13kN (+/-0.52). Statistical analyses revealed that differences in body mass explained only 2.3% of the variance in peak vertical force and 2.0% of the variance in peak horizontal braking force so normalization using body mass a covariate is not recommended when reporting front foot ground reaction forces in elite female fast bowlers. The mean time to the peak vertical force was 0.033s (+/-0.009) and the vertical loading rate was 121.31kNs(-1) (+/-73.78). Further work is required to determine the best ways to minimise and attenuate front foot ground reaction forces.

This study aimed to determine the prevalence of shoulder pain in female cricket fast bowlers and compare the shoulder rotation range of motion and strength of those bowlers with and without a history of shoulder pain. The active range of motion and isokinetic strength of the shoulder internal and external rotators was assessed in the bowling and non-bowling shoulders of 26 elite Australian female fast bowlers. Twelve bowlers had a history of shoulder pain. There were significant bilateral differences in external rotation range of motion for those bowlers without a history of shoulder pain (p<0.05), and in internal rotation range of motion for both the total cohort and those bowlers with a history of shoulder pain (p<0.05). There were no bilateral differences in average torques or average torque ratios, nor were there any differences in rotation range of motion, torques or torque ratios in the bowling shoulder between bowlers with and without a history of shoulder pain. There was an association between concentric internal rotation torque for the bowling shoulder and years of fast bowling (r(s)=0.45). Given the relatively small number of elite female cricketers, future research in this field will need to recruit fast bowlers from other cricket playing nations to increase the power of studies and provide more confidence in the statistical outcomes.

The aims of this study were to describe the current anthropometric profiles of elite Australian female and male cricket fast bowlers and establish a set of reference values useful for future investigations on player selection, talent identification, and training programme development. The participants were 26 female (mean age 22.5 years, s = 4.5; height 1.71 m, s = 0.05; body mass 66.2 kg, s = 7.5) and 26 male (mean age 23.9 years, s = 3.5; height 1.88 m, s = 0.05; body mass 87.9 kg, s = 8.2) fast bowlers. The anthropometric profiles included the measurement of skinfolds, and segment lengths, breadths, and girths. A series of derived variables assessing the distribution of subcutaneous adipose tissue, the bivariate overlap zone, relative body size and proportionality, and somatotype were also calculated. The male bowlers had larger length, breadth, and girth measurements than their female counterparts. There were differences in proportionality between the sexes, with only the male bowlers exhibiting characteristics that could be considered "large" relative to height. The female bowlers had a higher sum of seven skinfolds (P < 0.001), were more endomorphic (F(1,50) = 30.18, P < 0.001), and less mesomorphic (F(1,50 = 10.85, P < 0.01) than the male bowlers. These reference data should be useful to practitioners and researchers interested in cricket. Further research is needed to clarify why only male fast bowlers had variables that were proportionally large relative to height.

The inability of the between-bowlers methodology to control parameters external to technique could lead to erroneous significant and non-significant associations being reported between fast-bowling technique and ball release speed. Using Pearson's product - moment correlation, we first examined the effectiveness of a within-bowler methodology to identify associations between technique and ball release speed of an elite semi-open fast bowler over 20 deliveries. These results were compared with associations identified from a between-bowlers methodology in which 20 single-performance trials bowled by elite fast bowlers adopting a semi-open shoulder alignment were collated. Sufficient variation was observed in within-bowler ball release speed to allow f relationships to be identified between technique and ball release speed. Although greater variation in bowling technique parameters was observed in the between-bowlers methodology, no associations were identified between technique and ball release speed. Multiple stepwise regression analysis showed that 87.5% of the within-bowler variation in ball release speed can be attributed to run-up velocity, angular velocity of the bowling arm, vertical velocity of the non-bowling arm, and stride length. The within-bowler methodology provided significant detailed information about the individual bowler that the between-bowlers methodology overlooked, forming the basis of a performance enhancement programme. It is recommended that within-bowler methodology be used in future investigation of technique relationships.

Background: Hamstring injuries are among the most common non-contact injuries in sports. The Nordic hamstring (NH) exercise has been shown to decrease risk by increasing eccentric hamstring strength. Objective: The purpose of this systematic review and meta-analysis was to investigate the effectiveness of the injury prevention programs that included the NH exercise on reducing hamstring injury rates while factoring in athlete workload. Methods: Two researchers independently searched for eligible studies using the following databases: the Cochrane Central Register of Controlled Trials via OvidSP, AMED (Allied and Complementary Medicine) via OvidSP, EMBASE, PubMed, MEDLINE, SPORTDiscus, Web of Science, CINAHL and AusSportMed, from inception to December 2015. The keyword domains used during the search were Nordic, hamstring, injury prevention programs, sports and variations of these keywords. The initial search resulted in 3242 articles which were filtered to five articles that met the inclusion criteria. The main inclusion criteria were randomized controlled trials or interventional studies on use of an injury prevention program that included the NH exercise while the primary outcome was hamstring injury rate. Extracted data were subjected to meta-analysis using a random effects model. Results: The pooled results based on total injuries per 1000 h of exposure showed that programs that included the NH exercise had a statistically significant reduction in hamstring injury risk ratio [IRR] of 0.490 (95 % confidence interval [CI] 0.291-0.827, p = 0.008). Teams using injury prevention programs that included the NH exercise reduced hamstring injury rates up to 51 % in the long term compared with the teams that did not use any injury prevention measures. Conclusions: This systematic review and meta-analysis demonstrates that injury prevention programs that include NH exercises decrease the risk of hamstring injuries among soccer players. A protocol was registered in the International Prospective Register of Systematic Reviews, PROSPERO (CRD42015019912). [ABSTRACT FROM AUTHOR]

Objectives: Ankle injuries account for the highest percentage of injuries in netball, yet the chronic nature of ankle sprains is under reported within this population group. Chronic ankle instability is a term used to describe certain insufficiencies that persist after an acute ankle sprain. The aim of this study was to investigate recurrent sprain, perceived ankle instability and mechanical ankle instability in a cohort of netball players.Design: Cross-sectional study.Methods: Ninety-six female netball players (24.1±7.9 years) were recruited (42 club players and 54 inter-district players). Recurrent sprain was defined as two or more lifetime sprains to the same ankle. Perceived ankle instability was quantified with the Cumberland Ankle Instability Tool - Youth. Mechanical ankle instability was quantified via inversion-eversion rotations using an ankle arthrometer at torques of 3Nm.Results: Forty-seven percent of the cohort had recurrently sprained an ankle. Of the 69 players with a previously sprained ankle, 64% had a moderate-severe degree of perceived ankle instability. The total inversion-eversion angle was 31.1±8.7 degrees. Club players had more cases of moderate-severe perceived ankle instability (p=0.01) and larger inversion-eversion angles (p=0.001) compared to inter-district players.Conclusions: Recurrent ankle sprain and perceived ankle instability are easily identifiable aspects of chronic ankle instability shown to be prevalent within this cohort. Additional research is required to quantify a cut-off value for mechanical instability. Club netball players were found to have more counts of moderate-severe perceived ankle instability and larger inversion-eversion angles when compared to the inter-district netball players. [ABSTRACT FROM AUTHOR]

Background: The FIFA Medical and Research Centre (F-MARC) has designed a comprehensive warm-up program targeting muscular strength, body kinaesthetic awareness, and neuromuscular control during static and dynamic movements to decrease injury risk for soccer players. Prior studies have investigated the effectiveness of the F-MARC programs, but have not consistently reported a statistically significant reduction in injury and reduction in time loss due to injury from utilizing the program. Objective: The purpose of this study was to conduct a systematic review and meta-analysis of randomized controlled trials and interventional studies that evaluated the efficacy of the F-MARC injury prevention programs in soccer. Methods: Two independent researchers searched the relevant article databases. The keyword domains used during the search were 'F-MARC', 'FIFA 11+', 'the 11+', 'injury prevention programs', 'soccer', and variations of these keywords. The initial search resulted in 4299 articles which were filtered to nine articles that met the inclusion criteria. Main inclusion criteria were randomized controlled trials or interventional studies, use of F-MARC injury prevention programs, and the primary outcome measuring overall and lower extremity injuries. Extracted data were entered and analyzed using Comprehensive Meta-Analysis software, version 2 (CMA.V2). Results: The pooled results based on total injuries per 1000 h of exposure showed that F-MARC injury prevention programs had a statistically significant reduction in the overall injury risk ratio of 0.771 (95 % CI 0.647-0.918, p = 0.003) and the lower extremity injury risk ratio of 0.762 (95 % CI 0.621-0.935, p = 0.009). Moreover, FIFA '11+' had a statistically significant reduction in the overall injury risk ratio to 0.654 (95 % CI 0.537-0.798, p < 0.001) and the lower extremity injury risk ratio of 0.612 (95 % CI 0.475-0.788, p < 0.001). However, FIFA '11' did not reach significance for the lower extremity and overall injury reduction. It can be suggested that teams involved in the FIFA '11+' warm-up program will reduce injury rates by between 20 and 50 % in the long term compared with the teams that do not engage in F-MARC programs. Conclusions: This systematic review and meta-analysis indicated that use of F-MARC injury prevention programs, particularly the '11+' program, decreases the risk of injuries among soccer players. These data also support the case for the development and introduction of sport-specific programs. [ABSTRACT FROM AUTHOR]

Background: Chronic ankle instability (CAI) is a term used to identify certain insufficiencies of the ankle joint complex following an acute ankle injury. Acute ankle injuries are often associated with sporting mishaps; however, this review was the first to identify the aspects of CAI (perceived instability, mechanical instability and recurrent sprain), and persisting symptoms following an ankle sprain, that have been reported within sporting cohorts. Objective: To determine the presence of common aspects of CAI within individual sports. Methods: A systematic search of the MEDLINE, Web of Science, CINAHL, SPORTDiscus and AMED databases up until 1 October, 2013 produced 88 studies appropriate for review. A calculated weighted percentage of the outcome data allowed the comparison of figures across a range of sports. Results: Soccer, basketball and volleyball were the most represented sports and recurrent ankle injury/sprain was the most reported aspect of CAI. Soccer had the highest percentage of participants with recurrent sprain (61 %) and mechanical instability (38 %), whilst track and field had the highest percentage of participants with perceived instability (41 %). Gymnasts had the highest percentage of ankles with persisting symptoms following an initial ankle sprain. Conclusion: This review was the first to assess aspects of CAI within sporting cohorts and has identified limitations to the research reporting these data. The problem of CAI across a range of sports remains unclear and thus advocates the need for further controlled research in the area to ascertain the true extent of CAI within sporting populations. [ABSTRACT FROM AUTHOR]