How to explain the beneficial effects of platelet-rich plasma.

Platelet-rich plasma (PRP) is the platelet and leukocyte-containing plasmatic fraction of anticoagulated autologous blood. While evidence supporting the clinical use of PRP in dentistry is low, PRP is widely used in sports medicine, orthopedics, and dermatology. Its beneficial activity is commonly attributed to the growth factors released from platelets accumulating in PRP; however, evidence is indirect and not comprehensive. There is thus a demand to revisit PRP with respect to basic and translational science. This review is to (i) recapitulate protocols and tools to prepare PRP; (ii) to discuss the cellular and molecular composition of PRP with a focus on platelets, leukocytes, and the fibrin-rich extracellular matrix of coagulated plasma; and finally (iii) to discuss potential beneficial effects of PRP on a cellular and molecular level with an outlook on its current use in dentistry and other medical fields.

Characterizing the Effects of Concussion and Head Impact Exposure: Design, Methods, and Participant Traits of the CARE 2.0 Study.

OBJECTIVE: This article describes the design, methods, and participant characteristics of the second phase of the Concussion Assessment, Research, and Education (CARE) Consortium study ("CARE 2.0") of the effects of concussion and repetitive head impact exposure on neuropsychiatric health. METHODS: The authors conducted a prospective multisite observational study of male and female collegiate athletes and military service academy cadets and midshipmen participating in the CARE study. Participants were assessed at three time points: undergraduate baseline (UB), before departure from university or service academy (exit), and up to 6 years following graduation (postgrad) via an online battery of brain health assessments. Participant characteristics were compared across the three time points and four levels of head impact exposure. RESULTS: A total of 4,643 participants completed the exit assessment, and 3,981 completed the postgrad assessment. Relative to the UB assessment cohort, the exit and postgrad assessment cohorts differed with respect to the percentage of women, baseline Wechsler Test of Adult Reading scores, National Collegiate Athletic Association division category, sport contact level, and number of previous concussions. The median standardized difference across balancing variables, assessment time points, and degree of head impact exposure was 0.12 (with 90% of effect sizes ≤0.29). CONCLUSIONS: Although there were some statistically significant differences between participants across assessments, the effect sizes were modest, and overall the data suggest that the exit and postgrad cohorts reflect the characteristics of the baseline cohort. The CARE study design and its large, richly characterized sample provide an opportunity to answer important questions about cumulative and persistent effects of concussion and repetitive head impact exposure on neuropsychiatric health.

Pre-Participation Screenings Frequently Miss Occult Cardiovascular Conditions in Apparently Healthy Male Middle-Aged First-Time Marathon Runners.

INTRODUCTION: The optimal pre-participation screening strategy to identify athletes at risk for exercise-induced cardiovascular events is unknown. We therefore aimed to compare the American College of Sports Medicine (ACSM) and European Society of Cardiology (ESC) pre-participation screening strategies against extensive cardiovascular evaluations in identifying high-risk individuals among 35-50-year-old apparently healthy men. METHODS: We applied ACSM and ESC pre-participation screenings to 25 men participating in a study on first-time marathon running. We compared screening outcomes against medical history, physical examination, electrocardiography, blood tests, echocardiography, cardiopulmonary exercise testing, and magnetic resonance imaging. RESULTS: ACSM screening classified all participants as "medical clearance not necessary." ESC screening classified two participants as "high-risk." Extensive cardiovascular evaluations revealed ≥1 minor abnormality and/or cardiovascular condition in 17 participants, including three subjects with mitral regurgitation and one with a small atrial septal defect. Eleven participants had dyslipidaemia, six had hypertension, and two had premature atherosclerosis. Ultimately, three (12%) subjects had a serious cardiovascular condition warranting sports restrictions: aortic aneurysm, hypertrophic cardiomyopathy (HCM), and myocardial fibrosis post-myocarditis. Of these three participants, only one had been identified as "high-risk" by the ESC screening (for dyslipidaemia, not HCM) and none by the ACSM screening. CONCLUSION: Numerous occult cardiovascular conditions are missed when applying current ACSM/ESC screening strategies to apparently healthy middle-aged men engaging in their first high-intensity endurance sports event.

The International Olympic Committee framework on fairness, inclusion and nondiscrimination on the basis of gender identity and sex variations does not protect fairness for female athletes.

The International Olympic Committee (IOC) recently published a framework on fairness, inclusion, and nondiscrimination on the basis of gender identity and sex variations. Although we appreciate the IOC's recognition of the role of sports science and medicine in policy development, we disagree with the assertion that the IOC framework is consistent with existing scientific and medical evidence and question its recommendations for implementation. Testosterone exposure during male development results in physical differences between male and female bodies; this process underpins male athletic advantage in muscle mass, strength and power, and endurance and aerobic capacity. The IOC's "no presumption of advantage" principle disregards this reality. Studies show that transgender women (male-born individuals who identify as women) with suppressed testosterone retain muscle mass, strength, and other physical advantages compared to females; male performance advantage cannot be eliminated with testosterone suppression. The IOC's concept of "meaningful competition" is flawed because fairness of category does not hinge on closely matched performances. The female category ensures fair competition for female athletes by excluding male advantages. Case-by-case testing for transgender women may lead to stigmatization and cannot be robustly managed in practice. We argue that eligibility criteria for female competition must consider male development rather than relying on current testosterone levels. Female athletes should be recognized as the key stakeholders in the consultation and decision-making processes. We urge the IOC to reevaluate the recommendations of their Framework to include a comprehensive understanding of the biological advantages of male development to ensure fairness and safety in female sports.

The polymorphism T1470A of the SLC16A1 gene is associated with the lactate and ventilatory thresholds but not with fat oxidation capacity in young men.

PURPOSE: To examine the association of the single nucleotide polymorphism A1470T in the SLC16A1 gene with blood lactate accumulation during a graded exercise test and its associated metaboreflex. METHODS: Forty-six Latin-American men (Age: 27 ± 6 years; Body fat: 17.5 ± 4.7%) performed a graded exercise test on a treadmill for the assessment of maximal oxygen uptake (VO2max), lactate threshold (LT), ventilatory threshold (VT) and the exercise intensity corresponding to maximal fat oxidation rate (FATmax), via capillary blood samples and indirect calorimetry. Genomic DNA was extracted from a peripheral blood sample. Genotyping assay was carried out by real-time polymerase chain reaction to identify the A1470T polymorphism (rs1049434). RESULTS: Genotypes distribution were in Hardy-Weinberg equilibrium (X2 = 5.6, p > 0.05), observing allele frequencies of 0.47 and 0.53 for the A and T alleles, respectively. No difference in VO2max, body composition nor FATmax were observed across genotypes, whereas carriers of the TT genotype showed a higher LT (24.5 ± 2.2 vs. 15.6 ± 1.7 mL kg-1 min-1, p < 0.01) and VT in comparison to carriers of the AA + AT genotypes (32.5 ± 3.3 vs. 21.7 ± 1.5 mL kg-1 min-1, p < 0.01). Both, VO2max and the A1470T polymorphism were positively associated to the LT (R2 = 0.50, p < 0.01) and VT (R2 = 0.55, p < 0.01). Only VO2max was associated to FATmax (R2 = 0.39, p < 0.01). CONCLUSION: Independently of cardiorespiratory fitness, the A1470T polymorphism is associated to blood lactate accumulation and its associated ventilatory response during submaximal intensity exercise. However, the A1470 polymorphism does not influence fat oxidation capacity during exercise in young men.

Framing racial disparities within sports related concussion (SRC): an ecological framework for understanding biases and disparities in concussion care for black athletes.

Privilege and marginalization associated with racial background have been posited as contributors to why Black athletes face disparities within their care, treatment, and recovery from sport-related concussion (SRC). However, empirical findings have limited exploration on how disparate outcomes have emerged, and the interaction with systems of biases, power and disenfranchisement. To understand concussion care disparities, a qualitative content analysis was conducted in three phases: [I] identifying salient literature on racial differences for Black athletes with SRC (N = 29), [II] qualitative analysis of literature to determine salient topics, themes and patterns within the literature, and [III] constructing a novel ecological-systems framework that encapsulates the 'why' and 'how' related to psychosocial and sociocultural experiences of power, access, and biases for Black athletes. The content analysis yielded two patterns, where concussion care decisions are influenced by (1) biased, unconscious beliefs that posit Black athletes as uniquely invincible to injury and pain, and (2) inadequate access to concussion knowledge and resources, which both moderate SRC injury risk, diagnosis, recovery and outcomes. Ultimately, our novel framework provides a clear thread on how historical, macro-level policy and perceptions can impact micro-level clinical care and decision-making for Black athletes with SRC.

Factors affecting maximal oxygen uptake in prepubertal children: a systematic review and meta-analysis.

In pre-pubertal children the factors affecting maximal oxygen uptake have yet to be fully understood. Therefore, the purpose of this analysis is to present cardiorespiratory fitness in prepubertal boys and girls and to determine if there are any differences based on sex, exercise testing modality or if maximal or peak oxygen consumption metrics are used. PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed. For statistical analysis, multilevel models grounded in Bayesian principles were used. Selected studies obtained: maximal effort during the test, peak or maximal oxygen consumption (V̇O2) values, boys and girls (sex specific groups only) age under 11, cycle ergometry or treadmill, pre-intervention or no intervention data. In boys using cycle ergometry, 118 studies were included in the analysis, in boys using treadmill 115, in girls using cycle ergometry 83 and in girls using treadmill testing 95 study entries were included. As children get older, their cardiorespiratory fitness increases (P ≈ 100%). Studies with participants having smaller body mass have higher V̇O2 relative to body mass values (P ≈ 100%). Boys have higher V̇O2 values than girls (P ≈ 100%). Studies using treadmill reported higher values than those using cycle ergometer (P ≈ 100%). Regarding the influence of measurement method (max vs. peak) on V̇O2 values we did not find significant differences. In conclusion, we present reference values for cardiorespiratory fitness in prepubertal boys and girls using cycle ergometry or treadmill. Prepubertal boys have higher cardiorespiratory fitness than girls and using treadmill testing might be a preferred method to cycle ergometry, especially in older children. Maximal or peak oxygen consumption metrics might be used interchangeably in prepubertal children.

Imaging of soccer injuries in adolescent female athletes.

Soccer participation is increasing among female adolescents with a concomitant rise of injuries in this group. Age- and sex-related factors, such as the transition from skeletal immaturity to skeletal maturity as well as anatomic, physiologic, neuromuscular, and behavioral differences between females and males, all play a role in injury patterns for these athletes. Anterior cruciate ligament (ACL) tears in this group have received a great deal of attention in the medical literature and the media in recent years with increasing knowledge about causative factors, surgical management, and injury prevention. There have been fewer studies specifically focused on female adolescent soccer players in relation to other types of injuries, such as patellar dislocation/instability; other knee and ankle ligament tears; hip labral tears; muscle strains and tears; and overuse injuries such as apophysitis, patellofemoral pain syndrome, and bone stress injuries. Because imaging plays a critical role in diagnosis of soccer-related injuries in female adolescents, knowledge of the mechanisms of injury, imaging findings, and clinical considerations are essential for radiologists involved in the care of these patients.

Apophyseal injuries in soccer players.

Soccer is the most popular sport worldwide, and it is associated with high injury rates, with most of these injuries occurring in the lower extremities. Particularly, in youth soccer players with immature skeleton, the physeal plate is two to five times weaker than the surrounding fibrous structures, and therefore more vulnerable to injury. The physeal plate consists of epiphyses and apophyses, with the former serving as tendon attachment sites and being subject to traction forces. There are two types of apophyseal injury: (i) apophyseal avulsion, which consists of an acute separation across the physeal plate; and (ii) apophysitis, an injury caused by chronic and repetitive contraction of musculotendon unit, leading to inflammation of the growth plate cartilage. Apophyses of the hip and pelvis are the most commonly injured in youth soccer players, due to vigorous contractions during sports activities and the fact that they tend to fuse later compared to other epiphyseal centers, making them more susceptible to injury. In this review, we will discuss the anatomy of lower limb apophyses and clinical and imaging findings of apophyseal injuries in youth soccer players, as well as briefly review treatment options and complications.

Concussion diagnosis and recovery in relation to collegiate athletic department classification: a LIMBIC MATARS consortium investigation.

PURPOSE: We investigated time to reach concussion diagnosis and recovery milestones in collegiate athletes relative to their schools' National Collegiate Athletic Association (NCAA) classification. METHODS: We retrospectively examined 849 (43.1% female) concussion cases from 11 NCAA institutions (Division I Power 5 [n = 4], Division I Non-Power 5 [n = 4], and Division II/III [n = 3]) from the 2015-16 to 2019-20 athletic seasons. Our primary outcome measures were days to reach specific clinical milestones following concussion. RESULTS: Median (IQR) time from injury to diagnosis was significantly longer at Division II/III institutions (1 [0-4] days) compared to Division I Power 5 (0 [0-1] days) and Division I Non-Power 5 (0 [0-1] days) institutions (p < 0.001). Likewise, Division II/III athletes (15 [11-22] days) took significantly longer to return to sport after concussion than Division I Power 5 (10 [7-16] days) and Division I Non-Power 5 (11 [7-18.5] days) athletes (p < 0.001). CONCLUSION: Division II/III athletes had delayed concussion diagnoses and return to sport timelines compared to Division I athletes. Our results suggest that differences in sports medicine resources across NCAA divisions may influence injury recognition and recovery in collegiate athletes with concussion.

Incidence of injury and illness at the Beijing 2022 Paralympic Winter Games held in a closed-loop environment: a prospective cohort study of 7332 athlete days.

OBJECTIVE: To describe the epidemiology of injuries and illnesses sustained during the Beijing 2022 Paralympic Winter Games, organised in a closed-loop environment to adhere with COVID-19 restrictions. METHODS: Injuries and illnesses from all teams were recorded on a daily basis by team medical staff on a web-based form and by local organising committee medical (polyclinic) facilities and venue medical support. Duplicates recorded on both systems were removed. Incidence of injuries and illnesses are reported per 1000 athlete days (95% CI). RESULTS: 564 athletes (426 male and 138 female) representing 46 countries were monitored for the 13-day period of the Beijing 2022 Paralympic Winter Games (7332 athlete days). The overall incidences were 13.0 injuries (10.6-15.8) and 6.1 illnesses (4.5-8.4) per 1000 athlete days. The incidence of injury in alpine skiing (19.9; 15.2-26.1) was significantly higher compared with Nordic skiing, ice hockey and wheelchair curling (p<0.05), while the incidence of respiratory illness was significantly higher in Nordic skiing (1.6; 0.9-2.9) compared with alpine skiing, ice hockey and snowboarding (p<0.05). CONCLUSION: The incidence of both injury and illness at the Beijing 2022 Games were the lowest yet reported in the Paralympic Winter Games. The incidence of injury was highest in alpine skiing. These findings underscore the importance of ongoing vigilance and continued injury risk mitigation strategies to safeguard the well-being of athletes in these high-risk competitions. Respiratory illnesses were most commonly reported in Nordic skiing, which included the three cases of COVID-19 recorded at the games.

Focus areas and methodological characteristics of North American-based health disparity research in sports medicine: a scoping review.

OBJECTIVE: Health disparities are widely prevalent; however, little has been done to examine and address their causes and effects in sports and exercise medicine (SEM). We aimed to summarise the focus areas and methodology used for existing North American health disparity research in SEM and to identify gaps in the evidence base. DESIGN: Scoping review. DATA SOURCES: Systematic literature search of PubMed, Scopus, SPORTDiscus, CINAHL Plus with Full Text, Web of Science Core Collection and Cochrane Central Register of Controlled Trials. ELIGIBILITY CRITERIA: Full-text, peer-reviewed manuscripts of primary research, conducted in North America; published in the year 2000 or after, in English; and focusing on organised sports were included. RESULTS: 103 articles met inclusion criteria. Articles were classified into five focus areas: access to and participation in sports (n=45), access to SEM care (n=28), health-related outcomes in SEM (n=24), provider representation in SEM (n=5) and methodology (n=1). Race/ethnicity (n=39), socioeconomic status (n=28) and sex (n=27) were the most studied potential causes of health disparities, whereas sexual orientation (n=5), location (rural/urban/suburban, n=5), education level (n=5), body composition (n=5), gender identity (n=4) and language (n=2) were the least studied. Most articles (n=74) were cross-sectional, conducted on youth (n=55) and originated in the USA (n=90). CONCLUSION: Health disparity research relevant to SEM in North America is limited. The overall volume and breadth of research required to identify patterns in a heterogeneous sports landscape, which can then be used to inform positive change, need expansion. Intentional research focused on assessing the intersectionality, causes and consequences of health disparities in SEM is necessary.

Low socioeconomic status is associated with worse treatment outcomes in patients with Achilles tendinopathy.

OBJECTIVE: To assess whether there is a difference in symptom severity at baseline and 24 weeks follow-up between conservatively managed patients with Achilles tendinopathy (AT) with low socioeconomic status (SES) compared with those with high SES. METHODS: In this prospective cohort study, 200 patients with AT were included and treated according to current guidelines. We linked a neighbourhood SES indicator based on income, employment and education level and divided the patient population into quintiles, with Q1 being the highest SES and Q5 the lowest. Symptom severity at baseline and follow-up was assessed using the Victorian Institute of Sports Assessment-Achilles (VISA-A) score. Treatment adherence was not measured. We used a general linear model and the mean VISA-A scores at baseline and at 6, 12 and 24 weeks follow-up were compared between Q1 (n=45) and Q5 (n=39), while adjusting for age, sex, body mass index (BMI), Ankle Activity Score, symptom duration and baseline VISA-A score. RESULTS: Patients had a median age of 51 years and median BMI of 25.4, 40% were female. 74%, 70% and 58% of the participants completed the VISA-A at 6, 12 and 24 weeks, respectively. VISA-A scores at baseline were similar for Q1 and Q5 (43.9 and 41.8, p=0.591). At 24 weeks, there was a mean (95% CI) difference of 11.2 (1.0 to 21.3, p=0.032) points in favour of Q1 on the VISA-A score. CONCLUSION: AT patients with low SES may have worse outcomes when treated using the current guidelines. The difference in VISA-A score at 24 weeks is larger than the minimal clinically important difference and might be clinically relevant, but comes with uncertainty due to the large dispersion in the data. Clinicians need to consider the impact of social inequality when developing and implementing treatment plans.

Sport PRactice and its Effects on aortic size and valve function in bicuspid Aortic valve Disease: a cross-sectional report from the SPREAD study.

OBJECTIVE: Concerns exist about the possible detrimental effects of exercise training on aortic size and valve function in individuals with bicuspid aortic valve (BAV). This multicentre international study aimed to determine the characteristics of aortic size and valve function in athletes versus non-athletes with BAV and athletes with tricuspid aortic valve (TAV). METHODS: We enrolled competitive athletes with BAV and age- and sex-matched athletes with TAV and non-athletes with BAV. We assessed valve function, aortic size and biventricular measures using echocardiography. Individuals with established moderate-severe AV stenosis, regurgitation or significant aortic dilation were excluded from the study. RESULTS: The study population comprised 504 participants: 186 competitive athletes with BAV (84% males; age 30±11 years), 193 competitive athletes with TAV and 125 non-athletes with BAV. The aortic annulus was greater in athletes with BAV than athletes with TAV and non-athletes with BAV (p<0.001). Both athletic and non-athletic individuals with BAV had greater sinuses of Valsalva, sino-tubular junction and ascending aorta diameters than athletes with TAV (p<0.001). However, no significant differences were found between athletes and non-athletes with BAV. Left ventricular index volumes and mass were greater in athletes with BAV than in the other two groups (p<0.001). Individuals with BAV (athletes and non-athletes) had greater mean gradients than TAV athletes. CONCLUSION: This multicentre international study demonstrates no differences between athletes with BAV and non-athletes with BAV regarding aortic valve function or aortic dimensions. However, athletes with BAV have larger aortic diameters and a relatively worse valvular function than athletes with TAV.

'More than likely the men come first. That's just very frustrating'. A qualitative exploration of contextual factors affecting the implementation of injury prevention initiatives and the provision of effective injury management in elite-level women's club football in Ireland.

OBJECTIVES: The aim of our study was to explore the contextual factors that affect the implementation of football injury prevention initiatives and the provision of effective injury management in the Irish Women's National League (WNL). METHODS: We used a criterion-based purposive sampling approach to recruit coaches (n=7), players (n=17) and medical personnel (n=8) representing eight of the nine clubs in the WNL to participate in one-to-one semistructured interviews. Our study was located within an interpretivist, constructivist research paradigm. The interview data were analysed using reflexive thematic analysis. RESULTS: The participants identified academic and work pressures, financial challenges, conflict with college football, inadequate facilities and gender inequity as being barriers to the implementation of injury prevention initiatives and the provision of effective injury management. Financial constraints within clubs were perceived to limit the provision of medical care and strength and conditioning (S&C) support and this was deemed to be associated with a heightened risk of injuries. CONCLUSION: Specific contextual factors were identified which curtail the implementation of injury prevention initiatives and the provision of effective injury management in elite-level women's club football in Ireland. Gender inequity was identified as one of the factors impacting the availability of high-quality medical care, S&C support, as well as access to training and match facilities. Our results provide new insights that could be used to inform the design and implementation of injury prevention and management initiatives for women football players in Ireland.

If we build it together, will they use it? A mixed-methods study evaluating the implementation of Prep-to-Play PRO: an injury prevention programme for women's elite Australian Football.

OBJECTIVES: We evaluated the implementation of Prep-to-Play PRO, an injury prevention programme for women's elite Australian Football League (AFLW). METHODS: The Reach, Effectiveness, Adoption, Implementation and Maintenance (RE-AIM) of Prep-to-Play PRO were assessed based on the proportion of AFLW players and/or staff who: were aware of the programme (R), believed it may reduce anterior cruciate ligament injury (E), attempted to implement any/all programme components (A), implemented all intended components as practically as possible (I) and intended future programme implementation (M). Quantitative and qualitative data were triangulated to assess 58 RE-AIM items (evidence of yes/no/unsure/no evidence) and the 5 RE-AIM dimensions (fully achieved=evidence of yes on >50% dimension items, partially achieved=50% of items evidence of yes and 50% unsure or 50% mix of unsure and unanswered, or not met=evidence of yes on <50% dimension items). RESULTS: Multiple sources including AFLW training observations (n=7 total), post-implementation surveys (141 players, 25 staff), semistructured interviews (19 players, 13 staff) and internal programme records (9 staff) contributed to the RE-AIM assessment. After the 2019 season, 8 of 10 (80%) AFLW clubs fully met all five RE-AIM dimensions. All 10 clubs participating in the AFLW fully achieved the reach (R) dimension. One club partially achieved the implementation (I) dimension, and one club partially achieved the effectiveness (E) and adoption (A) dimensions. CONCLUSION: The Prep-to-Play PRO injury prevention programme for the AFLW achieved high implementation, possibly due to the programme's deliberately flexible approach coupled with our pragmatic definition of implementation. Engaging key stakeholders at multiple ecological levels (organisation, coaches, athletes) throughout programme development and implementation likely enhanced programme implementation.

Injury incidence according to athlete impairment type during the 2012 and 2016 Summer Paralympic Games: a combined analysis of 101 108 athlete days.

OBJECTIVES: The relationship between sport-related injuries and Para athlete impairment type has not yet been comprehensively studied. This study aimed to describe injury incidence according to athlete impairment type during the London 2012 and Rio 2016 Summer Paralympic Games, by sex, age, Games period, chronicity and anatomical area. METHODS: A combined analysis of 7222 athletes was conducted comprising 101 108 athlete days, using pooled data. Internet sources were used to identify impairments of registered athletes. Impairment types: brain disorders (BD), limb deficiency, neuromuscular disorders (NMD), spinal cord-related disorders, visual impairment (VI) and 'all others' (OTH: impaired passive range of movement, intellectual impairment, leg length difference, short stature and unknown impairments). Results by impairment type are reported as univariate unadjusted incidences (injuries/1000 athlete days; 95% CIs). Statistical significance between impairment types was determined when 95% CIs did not overlap. RESULTS: The overall crude unadjusted incidence of injury was 11.1 (95% CI 10.4 to 11.9), significantly higher in VI (13.7 (95% CI 11.0 to 15.7)) and NMD (13.3 (95% CI 11.1 to 16.1)) compared with BD (9.1 (95% CI 7.7 to 10.8)). Acute (sudden onset) (8.6 (95% CI 7.3 to 10.1)) and lower limb (6.6 (95% CI 5.4 to 8.1)) injuries were higher among athletes with VI, while athletes with NMD had a higher incidence of repetitive (gradual onset) (5.9 (95% CI 4.3 to 8.0)) and upper limb (6.9 (95% CI 5.2 to 9.0)) injuries compared with other impairments. CONCLUSIONS: Incidence and type of injuries differed between athlete impairment types. Athletes with VI or NMD sustained the highest incidence of injury, and athletes with BD had the lowest. Findings of this study can inform the management of competition-related injuries in Para athletes.

Heat-related risk at Paris 2024: a proposal for classification and review of International Federations policies.

Several International Federations (IFs) employ specific policies to protect athletes' health from the danger of heat. Most policies rely on the measurement of thermal indices such as the Wet Bulb Globe Temperature (WBGT) to estimate the risk of heat-related illness. This review summarises the policies implemented by the 32 IFs of the 45 sports included in the Paris 2024 Olympic Games. It provides details into the venue type, measured parameters, used thermal indices, measurement procedures, mitigation strategies and specifies whether the policy is a recommendation or a requirement. Additionally, a categorisation of sports' heat stress risk is proposed. Among the 15 sports identified as high, very high or extreme risk, one did not have a heat policy, three did not specify any parameter measurement, one relied on water temperature, two on air temperature and relative humidity, seven on WBGT (six measured on-site and one estimated) and one on the Heat Stress Index. However, indices currently used in sports have been developed for soldiers or workers and may not adequately reflect the thermal strain endured by athletes. Notably, they do not account for the athletes' high metabolic heat production and their level of acclimation. It is, therefore, worthwhile listing the relevance of the thermal indices used by IFs to quantify the risk of heat stress, and in the near future, develop an index adapted to the specific needs of athletes.

It's about time to exercise: development of the Exercise Participation Explained in Relation to Time (EXPERT) model.

A perceived 'lack of time' is consistently the most commonly reported barrier to exercise. However, the term fails to capture the multifaceted nature of time-related factors. Recognising the need for a more comprehensive analysis of 'lack of time' as a barrier to exercise, the aim of this study was to develop the exercise participation explained in relation to time (EXPERT) model. The model was developed through a sequential process including (1) an umbrella literature review of time as a barrier, determinant, and correlate of physical activity; (2) a targeted review of existing temporal models; (3) drafting the model and refining it via discussions between eight authors; (4) a three-round Delphi process with eight panel members; and (5) consultations with seven experts and potential end-users. The final EXPERT model includes 31 factors within four categories: (1) temporal needs and preferences for exercise (ie, when and how long does an individual need/want to exercise), (2) temporal autonomy for exercise (ie, autonomy in scheduling free time for exercise), (3) temporal conditions for exercise (ie, available time for exercise) and (4) temporal dimensions of exercise (ie, use of time for exercise). Definitions, examples and possible survey questions are presented for each factor. The EXPERT model provides a comprehensive framework for understanding the multi-dimensional nature of 'time' as it relates to exercise participation. It moves beyond the simplistic notion of 'lack of time' and delves into the complexity of time allocation in the context of exercise. Empirical and cross-cultural validations of the model are warranted.

Baseline clinical and MRI risk factors for hamstring reinjury showing the value of performing baseline MRI and delaying return to play: a multicentre, prospective cohort of 330 acute hamstring injuries.

OBJECTIVES: Studies identifying clinical and MRI reinjury risk factors are limited by relatively small sample sizes. This study aimed to examine the association between baseline clinical and MRI findings with the incidence of hamstring reinjuries using a large multicentre dataset. METHODS: We merged data from four prospective studies (three randomised controlled trials and one ongoing prospective case series) from Qatar and the Netherlands. Inclusion criteria included patients with MRI-confirmed acute hamstring injuries (<7 days). We performed multivariable modified Poisson regression analysis to assess the association of baseline clinical and MRI data with hamstring reinjury incidence within 2 months and 12 months of follow-up. RESULTS: 330 and 308 patients were included in 2 months (31 (9%) reinjuries) and 12 months (52 (17%) reinjuries) analyses, respectively. In the 2-month analysis, the presence of discomfort during the active knee extension test was associated with reinjury risk (adjusted risk ratio (ARR) 3.38; 95% CI 1.19 to 9.64). In the 12 months analysis, the time to return to play (RTP) (ARR 0.99; 95% CI 0.97 to 1.00), straight leg raise angle on the injured leg (ARR 0.98; 95% CI 0.96 to 1.00), the presence of discomfort during active knee extension test (ARR 2.52; 95% CI 1.10 to 5.78), the extent of oedema anteroposterior on MRI (ARR 0.74; 95% CI 0.57 to 0.96) and myotendinous junction (MTJ) involvement on MRI (ARR 3.10; 95% CI 1.39 to 6.93) were independently associated with hamstring reinjury. CONCLUSIONS: Two clinical findings (the presence of discomfort during active knee extension test, lower straight leg raise angle on the injured leg), two MRI findings (less anteroposterior oedema, MTJ involvement) and shorter time to RTP were independently associated with increased hamstring reinjury risk. These findings may assist the clinician to identify patients at increased reinjury risk following acute hamstring injury. TRIAL REGISTRATION NUMBERS: NCT01812564; NCT02104258; NL2643; NL55671.018.16.