M. Drew

Performance success or failure is influenced by weeks lost to injury and illness in elite Australian track and field athletes: A 5-year prospective study

OBJECTIVES To investigate the impact of training modification on achieving performance goals. Previous research demonstrates an inverse relationship between injury burden and success in team sports. It is unknown whether this relationship exists within individual sport such as athletics. DESIGN A prospective, cohort study (n=33 International Track and Field Athletes; 76 athlete seasons) across five international competition seasons. METHODS Athlete training status was recorded weekly over a 5-year period. Over the 6-month preparation season, relationships between training weeks completed, the number of injury/illness events and the success or failure of a performance goal at major championships was investigated. Two-by-two table were constructed and attributable risks in the exposed (AFE) calculated. A mixed-model, logistic regression was used to determine the relationship between failure and burden per injury/illness. Receiver Operator Curve (ROC) analysis was performed to ascertain the optimal threshold of training week completion to maximise the chance of success. RESULTS Likelihood of achieving a performance goal increased by 7-times in those that completed >80% of planned training weeks (AUC, 0.72; 95%CI 0.64-0.81). Training availability accounted for 86% of successful seasons (AFE=0.86, 95%CI, 0.46 to 0.96). The majority of new injuries occurred within the first month of the preparation season (30%) and most illnesses occurred within 2-months of the event (50%). For every modified training week the chance of success significantly reduced (OR=0.74, 95%CI 0.58 to 0.94). CONCLUSIONS Injuries and illnesses, and their influence on training availability, during preparation are major determinants of an athletes chance of performance goal success or failure at the international level.

Sports-related workload and injury risk: simply knowing the risks will not prevent injuries

Training loads contribute to sports injury risk but their mitigation has rarely been considered in a sports injury prevention framework. A key concept behind monitoring training loads for injury prevention is to screen for those at increased risk of injury so that workloads can be adjusted to minimise these risks. This review describes how advances in management of workload can be applied as a preventive measure. Primary prevention involves screening for preparticipation load risk factors, such as low training loads, prior to a training period or competition. Secondary prevention involves screening for workloads that are known to precede an injury developing so that modification can be undertaken to mitigate this risk. Tertiary prevention involves rehabilitation practices that include a graded return to training programme to reduce the risk of sustaining a subsequent injury. The association of training loads with injury incidence is now established. Prevention measures such as rule changes that affect the workload of an athlete are universal whereas those that address risk factors of an asymptomatic subgroup are more selective. Prevention measures, when implemented for asymptomatic individuals exhibiting possible injury risk factors, are indicated for an athlete at risk of developing a sports injury. Seven key indicated risks and associated prevention measures are proposed.

Reliability of externally fixed dynamometry hamstring strength testing in elite youth football players.

OBJECTIVES To investigate inter and intra-tester reliability of an externally fixed dynamometry unilateral hamstring strength test, in the elite sports setting. DESIGN Reliability study. METHODS Sixteen, injury-free, elite male youth football players (age=16.81±0.54 years, height=180.22±5.29cm, weight 73.88±6.54kg, BMI=22.57±1.42) gave written informed consent. Unilateral maximum isometric peak hamstring force was evaluated by externally fixed dynamometry for inter-tester, intra-day and intra-tester, inter-week reliability. The test position was standardised to correlate with the terminal swing phase of the gait running cycle. RESULTS Inter and intra-tester values demonstrated good to high levels of reliability. The intra-class coefficient (ICC) for inter-tester, intra-day reliability was 0.87 (95% CI=0.75-0.93) with standard error of measure percentage (SEM%) 4.7 and minimal detectable change percentage (MDC%) 12.9. Intra-tester, inter-week reliability results were ICC 0.86 (95% CI, 0.74-0.93), SEM% 5.0 and MDC% 14.0. CONCLUSIONS This study demonstrates good to high inter and intra-tester reliability of isometric externally fixed dynamometry unilateral hamstring strength testing in the regular elite sport setting involving elite male youth football players. The intra-class coefficient in association with the low standard error of measure and minimal detectable change percentages suggest that this procedure is appropriate for clinical and academic use as well as monitoring hamstring strength in the elite sport setting.

Injuries impair the chance of successful performance by sportspeople: a systematic review

Background Cost–benefit analyses have been proposed for determining acceptable risk of injury regarding training and competition participation. Currently, there is no best evidence synthesis of the literature evaluating the relationship between injury/illness and chance of success or failure. Objective To evaluate the relationship between injury and/or illness and success and/or failure in athletic populations (individual and team sports). Methods This review was prospectively registered (PROSPERO CRD42016036729) and a systematic electronic search was conducted in May 2016. Inclusion criterion was any study design describing the association between injury and/or illness and success or failure in athletic performance. Two independent authors screened search results, performed data extraction and assessed methodological quality and strength of evidence using a modified Downs and Black appraisal tool and a modified van Tulder method, respectively. Results Of 10 546 titles identified, 14 satisfied the inclusion criteria and 7 had low risk of bias. Outcome measures associated with success and/or failure included: (1) availability of team members, (2) injury incidence, (3) injury burden, (4) squad utilisation and (5, 6) precompetition and in-competition injury. There was strong evidence that (1) increased availability of team members/athletes decreased the risk of failure and (2) precompetition and in-competition injuries were associated with increased risk of failure. Conclusions Injuries have a detrimental impact on team and individual athletic success. Increased player availability improves chances of success. Conversely, injuries sustained both prior to and during competition may increase risk of failure. Injury prevention should therefore be a priority for maximising athletic performance.

Resisted adduction in hip neutral is a superior provocation test to assess adductor longus pain: An experimental pain study.

The criterion of long‐standing groin pain diagnoses in athletes usually relies on palpation and clinical tests. An experimental pain model was developed to examine the clinical tests under standardized conditions. Pain was induced by hypertonic saline injected into the proximal adductor longus (AL) tendon or rectus femoris (RF) tendon in 15 healthy male participants. Isotonic saline was injected contralaterally as a control. Pain intensity was assessed on a visual analog scale (VAS). Resisted hip adduction at three different angles and trunk flexion were completed before, during, and after injections. Pain provocation in the presence of experimental pain was recorded as a true positive compared with pain provocation in the non‐pain conditions. Similar peak VAS scores were found after hypertonic saline injections into the AL and RF and both induced higher VAS scores than isotonic saline (P < 0.01). Adduction at 0° had the greatest positive likelihood ratio (+LR = 2.8, 95%CI: 1.09–7.32) with 45° (−LR = 0.0, 95%CI: 0.00–1.90) and 90° (−LR = 0.0, 95%CI: 0.00–0.94) having the lowest negative LR. This study indicates that the 0° hip adduction test resisted at the ankles optimizes the diagnostic procedure without compromising diagnostic capacity to identify experimental groin pain. Validation in clinical populations is warranted.

Time to bin the term ‘overuse’ injury: is ‘training load error’ a more accurate term?

We read the recent systematic review on the prevalence, incidence and risk factors for overuse injuries of the wrist in young athletes and agree with the conclusion that age and early specialisation (early training commencement) are risk factors for injury.1 The study highlighted training intensity as a risk factor for overuse injuries. Given changes in training loads precede the onset of injury in cricket,2 football (soccer)3 and Australian football,4 we consider that overuse injuries can be considered errors in training load prescription and labelled as such. Care should also be taken with broadly labelling training intensity as a risk factor as moderate training loads are protective against injury Gabbetts ‘training injury prevention paradox’.5 ,6 High training loads may predispose to …

Is subsequent lower limb injury associated with previous injury? A systematic review and meta-analysis

Background Previous injury is a strong risk factor for recurrent lower limb injury in athletic populations, yet the association between previous injury and a subsequent injury different in nature or location is rarely considered. Objective To systematically review data on the risk of sustaining a subsequent lower limb injury different in nature or location following a previous injury. Methods Eight medical databases were searched. Studies were eligible if they reported lower limb injury occurrence following any injury of a different anatomical site and/or of a different nature, assessed injury risk, contained athletic human participants and were written in English. Two reviewers independently applied the eligibility criteria and performed the risk of bias assessment. Meta-analysis was conducted using a random effects model. Results Twelve studies satisfied the eligibility criteria. Previous history of an ACL injury was associated with an increased risk of subsequent hamstring injury (three studies, RR=2.25, 95% CI 1.34 to 3.76), but a history of chronic groin injury was not associated with subsequent hamstring injury (three studies, RR=1.14, 95% CI 0.29 to 4.51). Previous lower limb muscular injury was associated with an increased risk of sustaining a lower limb muscular injury at a different site. A history of concussion and a variety of joint injuries were associated with an increased subsequent lower limb injury risk. Conclusions The fact that previous injury of any type may increase the risk for a range of lower limb subsequent injuries must be considered in the development of future tertiary prevention programmes. Systematic review registration number CRD42016039904 (PROSPERO).

A multifactorial evaluation of illness risk factors in athletes preparing for the Summer Olympic Games

OBJECTIVES Illness can disrupt training and competition performance of athletes. Few studies have quantified the relative contribution of the known medical, behavioural and lifestyle risk factors. DESIGN Cross-sectional. METHODS Olympic athletes from 11 sports (n=221) were invited to complete questionnaires administered nine months before the Rio 2016 Olympic Games. These included the Depression, Anxiety and Stress Questionnaire (DASS-21), Perceived Stress Scale (PSS), Dispositional Resilience Scale (DRS), Recovery-Stress Questionnaire (REST-Q-52 item), Low Energy in Females Questionnaire (LEAF-Q), a modified Personal and Household Hygiene questionnaire, Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index, and custom-made questionnaires on probiotic usage and travel. An illness (case) was defined as an event which limited training or competition for greater hours in the prior month. Odds ratios and attributable fractions in the population (AFP) were utilised for categorical variables with independent t-tests or Wilcoxon rank-sum for continuous variables. RESULTS Eighty-one athletes responded (male, n=26; female, n=55). There were 16 illness cases and 65 controls. Female athletes were at higher odds of illness (OR=9.4, 95%CI 1.3-410, p=0.01, AFP=0.84). Low energy availability (LEAF-Q score ≥8: OR=7.4, 95%CI 0.78-352, p=0.04, AFP=0.76), depression symptoms (DASS-21: depression score >4, OR=8.4, 95%CI 1.1-59, p<0.01; AFP=0.39) and higher perceived stress (PSS: 10-item, p=0.04) were significantly associated with illness. CONCLUSIONS Female sex, low energy availability, and mental health are associated with sports incapacity (time loss) due to illness. Low energy availability had high attributable fractions in the population and stands out as a primary association with illness.

Yes, rolling averages are a good way to assess training load for injury prevention. Is there a better way? Probably, but we have not seen the evidence

The acute:chronic workload ratio (ACWR) is evidence based1 ,2 and is strongly supported by the available literature.3 Other models of injury risk have yet to show such support. We find …

Imaging and clinical tests for the diagnosis of long-standing groin pain in athletes. A systematic review

OBJECTIVES To examine the validity of clinical tests available for the diagnosis of longstanding groin pain in athletes. DESIGN Systematic review. METHOD A published search strategy of MeSH terms in MEDLINE, CINAHL, EMBASE, and SportDiscuss. INCLUSION CRITERIA diagnostic studies relating to athletic groin pain, professional or semi-professional athletes, symptoms lasting for more than six weeks, and not limited by age or gender. A priori exclusion criteria were utilised. OUTCOME MEASURES QUADAS tool, sensitivity and specificity, likelihood ratios and predictive values of the reported tests and investigations. RESULTS 577 Journal articles were identified. Five studies met all requirements. Sensitivity and specificity of clinical tests ranged between 30 and 100% and 88 and 95% respectively with negative likelihood ratio of 0.15-0.78 and positive likelihood ratios of 1.0-11.0. Sensitivity and specificity of investigations (MRI, herniography, and dynamic ultrasound) ranged between 68% and 100% as well as 33% and 100% respectively with negative likelihood ratios between 0 and 0.32 and positive likelihood ratios between 1.5 and 8.1. CONCLUSION There is a lack of validated diagnostic clinical tests available for clinicians and a lack of symptomology being evaluated. It is recommended that a reference standard should be applied and data should be reported in sufficient detail to calculate diagnostic statistics that is useful to the clinician.