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Concept: International Association of Athletics Federations

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Assess exertional heat illness (EHI) history and preparedness in athletes competing in a World Athletics Championships under hot/humid conditions and identify the factors associated with preparedness strategies.

Concepts: Cohort study, Cohort, Epidemiology, Evaluation methods, International Association of Athletics Federations, IAAF World Championships in Athletics

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The International Association for Athletics Federations (IAAF) has been granted 2 years to submit further evidence showing a correlation between higher levels of testosterone and a competitive advantage. This article first presents the case of Caster Semenya, which triggered the drafting by IAAF of the regulations on eligibility of female athletes to compete in the female category in 2011. Then the IAAF regulations are critically analyzed from a scientific and ethical point of view. Finally, the Court of Arbitration for Sport decision to suspend the regulations pending further evidence provided by IAAF, and what this means for the future of sports, is discussed.

Concepts: Ethics, International Association of Athletics Federations, 2009 World Championships in Athletics – Women's 800 metres

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We investigated whether heart rate (HR)-derived parameters are accurate performance predictors in endurance recreational runners. One hundred thirty recreational athletes completed an incremental running test (4´running + 1´rest). After each stage, we recorded HR, % of maximum HR (%HRmax), and blood lactate. We also assessed HR after each recovery period, and calculated lactate and HR recovery thresholds and HR deflection point. We tested these parameters for associations with running performance, as measured by peak treadmill speed (PTS) and personal best International Association of Athletics Federations (IAAF) score. The %HRmax at 14.5 km·h-1correlated with PTS (r = -0.92), and IAAF score (rho = -0.80). The magnitudes of the correlations of lactate-related parameters with PTS (|r| = 0.84 to 0.86) or IAAF score (|rho| = 0.70 to 0.77) in absolute values were slightly lower. The correlations detected between other HR-derived parameters and running performance were weaker (|r or rho| = 0.24 to 0.70). Regression models identified %HRmax at 14.5 km·h-1as the strongest predictor of both PTS (β = -0.72) and IAAF score (β = -0.72). Consequently, tests based on %HRmax may provide a non-invasive and inexpensive alternate method for predicting the performance of these athletes.

Concepts: Regression analysis, Prediction, Futurology, Test method, The Strongest, Predictor, Absolute value, International Association of Athletics Federations

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Ranking enables coaches, sporting authorities, and pundits to determine the relative performance of individual athletes and teams in comparison to their peers. While ranking is relatively straightforward in sports that employ traditional leagues, it is more difficult in sports where competition is fragmented (e.g. athletics, boxing, etc.), with not all competitors competing against each other. In such situations, complex points systems are often employed to rank athletes. However, these systems have the inherent weakness that they frequently rely on subjective assessments in order to gauge the calibre of the competitors involved. Here we show how two Internet derived algorithms, the PageRank (PR) and user preference (UP) algorithms, when utilised with a simple ‘who beat who’ matrix, can be used to accurately rank track athletes, avoiding the need for subjective assessment. We applied the PR and UP algorithms to the 2015 IAAF Diamond League men’s 100m competition and compared their performance with the Keener, Colley and Massey ranking algorithms. The top five places computed by the PR and UP algorithms, and the Diamond League ‘2016’ points system were all identical, with the Kendall’s tau distance between the PR standings and ‘2016’ points system standings being just 15, indicating that only 5.9% of pairs differed in their order between these two lists. By comparison, the UP and ‘2016’ standings displayed a less strong relationship, with a tau distance of 95, indicating that 37.6% of the pairs differed in their order. When compared with the standings produced using the Keener, Colley and Massey algorithms, the PR standings appeared to be closest to the Keener standings (tau distance = 67, 26.5% pair order disagreement), whereas the UP standings were more similar to the Colley and Massey standings, with the tau distances between these ranking lists being only 48 (19.0% pair order disagreement) and 59 (23.3% pair order disagreement) respectively. In particular, the UP algorithm ranked ‘one-off’ victors more highly than the PR algorithm, suggesting that the UP algorithm captures alternative characteristics to the PR algorithm, which may more suitable for predicting future performance in say knockout tournaments, rather than for use in competitions such as the Diamond League. As such, these Internet derived algorithms appear to have considerable potential for objectively assessing the relative performance of track athletes, without the need for complicated points equivalence tables. Importantly, because both algorithms utilise a ‘who beat who’ model, they automatically adjust for the strength of the competition, thus avoiding the need for subjective decision making.

Concepts: Competition, Perfect competition, Non-parametric statistics, Ranking, Binary relation, International Association of Athletics Federations, Tournament, IAAF Diamond League

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Extreme environmental conditions present athletes with diverse challenges; however, not all sporting events are limited by thermoregulatory parameters. The purpose of this leading article is to identify specific instances where hot environmental conditions either compromise or augment performance and, where heat acclimation appears justified, evaluate the effectiveness of pre-event acclimation processes. To identify events likely to be receptive to pre-competition heat adaptation protocols, we clustered and quantified the magnitude of difference in performance of elite athletes competing in International Association of Athletics Federations (IAAF) World Championships (1999-2011) in hot environments (>25 °C) with those in cooler temperate conditions (<25 °C). Athletes in endurance events performed worse in hot conditions (~3 % reduction in performance, Cohen's d > 0.8; large impairment), while in contrast, performance in short-duration sprint events was augmented in the heat compared with temperate conditions (~1 % improvement, Cohen’s d > 0.8; large performance gain). As endurance events were identified as compromised by the heat, we evaluated common short-term heat acclimation (≤7 days, STHA) and medium-term heat acclimation (8-14 days, MTHA) protocols. This process identified beneficial effects of heat acclimation on performance using both STHA (2.4 ± 3.5 %) and MTHA protocols (10.2 ± 14.0 %). These effects were differentially greater for MTHA, which also demonstrated larger reductions in both endpoint exercise heart rate (STHA: -3.5 ± 1.8 % vs MTHA: -7.0 ± 1.9 %) and endpoint core temperature (STHA: -0.7 ± 0.7 % vs -0.8 ± 0.3 %). It appears that worthwhile acclimation is achievable for endurance athletes via both short-and medium-length protocols but more is gained using MTHA. Conversely, it is also conceivable that heat acclimation may be counterproductive for sprinters. As high-performance athletes are often time-poor, shorter duration protocols may be of practical preference for endurance athletes where satisfactory outcomes can be achieved.

Concepts: Time, Game theory, Term, Adaptation, Acclimatization, Augment, Sprinter, International Association of Athletics Federations

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In 2011, the International Association of Athletics Federations (IAAF) and IOC introduced a ‘hyperandrogenism’ rule that excluded women with a serum testosterone >10 nmol/L from participating in elite sport. This rule was based on the false premise that the greater lean body mass in men was a consequence of their higher serum testosterone. This rule did not have scientific backing and the Court of Arbitration for Sport subsequently rescinded the rule following an appeal from an Indian athlete barred from the Commonwealth Games. This review covers the scientific knowledge about the development and regulation of body composition in humans but also considers the lessons learnt from evolution and breeding in animals. The importance of heredity has been documented in family and twin studies. The roles of growth hormone and sex steroids are reviewed. The Androgen Insensitivity Syndrome (AIS) is considered as a model of the role of testosterone in development of body composition and also as evidence of the importance of other factors carried on the Y-chromosome that are of prime importance but have been systematically ignored. Finally the key factors determining body composition are considered and placed in a suggested order of importance.

Concepts: Growth hormone, Testosterone, SRY, Anabolic steroid, Androgen receptor, Androgen insensitivity syndrome, XY sex-determination system, International Association of Athletics Federations

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The aim of the present study was to analyze how many finalists of the International Association of Athletics Federations (IAAF) World Junior Championships (WJC) in the middle and long-distance track events had dropped out from high-level competitions.

Concepts: United Arab Emirates, Track and field athletics, International Association of Athletics Federations, IAAF World Junior Championships in Athletics

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The International Association of Athletics Federations (IAAF) and the International Olympic Committee (IOC) adopted testosterone level criteria for eligibility (i.e. 10 nmol/l or 290 ng/dl in blood for IAAF, levels ‘within the male range’ for IOC) to compete in the ‘includes females’ category. The policies address the assertion that women with very high endogenous testosterone (unless they are androgen-resistant) have an unfair advantage over women with lower natural levels. Recently, the Court of Arbitration for Sport suspended the ‘hyperandrogenism regulation’ by the IAAF, but added: ‘since there are separate categories of male and female competition, it is necessary for the IAAF to formulate a basis for the division of athletes into male and female categories for the benefit of the broad class of female athletes. The basis chosen should be necessary, reasonable and proportionate to the legitimate objective being pursued’ [Branch J: Dutee Chand, Female Sprinter with High Testosterone Level, Wins Right to Compete. The New York Times, July 27, 2015]. An analysis of available evidence below - scientific as well as experiential - suggests that androgen-based criteria can, in fact, be rationally defended as the best currently available and practical approach to determine eligibility for competition in the ‘includes females’ category. However, to justify such policies, the IOC and IAAF must also show them to be not only rational, but also fair, necessary, and consistent with the treatment of athletes with other endogenous non-physiologic advantages.

Concepts: Human, Female, Gender, Testosterone, Olympic Games, 2008 Summer Olympics, International Olympic Committee, International Association of Athletics Federations

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The GH-2000 and GH-2004 projects have developed a method for detecting GH misuse based on measuring insulin-like growth factor-I (IGF-I) and the amino-terminal pro-peptide of type III collagen (P-III-NP). The objectives were to analyze more samples from elite athletes to improve the reliability of the decision limit estimates, to evaluate whether the existing decision limits needed revision, and to validate further non-radioisotopic assays for these markers. The study included 998 male and 931 female elite athletes. Blood samples were collected according to World Anti-Doping Agency (WADA) guidelines at various sporting events including the 2011 International Association of Athletics Federations (IAAF) World Athletics Championships in Daegu, South Korea. IGF-I was measured by the Immunotech A15729 IGF-I IRMA, the Immunodiagnostic Systems iSYS IGF-I assay and a recently developed mass spectrometry (LC-MS/MS) method. P-III-NP was measured by the Cisbio RIA-gnost P-III-P, Orion UniQ™ PIIINP RIA and Siemens ADVIA Centaur P-III-NP assays. The GH-2000 score decision limits were developed using existing statistical techniques. Decision limits were determined using a specificity of 99.99% and an allowance for uncertainty because of the finite sample size. The revised Immunotech IGF-I - Orion P-III-NP assay combination decision limit did not change significantly following the addition of the new samples. The new decision limits are applied to currently available non-radioisotopic assays to measure IGF-I and P-III-NP in elite athletes, which should allow wider flexibility to implement the GH-2000 marker test for GH misuse while providing some resilience against manufacturer withdrawal or change of assays. Copyright © 2015 John Wiley & Sons, Ltd.

Concepts: Measurement, Insulin-like growth factor 1, Growth hormone, Uncertainty, South Korea, World Anti-Doping Agency, International Association of Athletics Federations, IAAF World Championships in Athletics

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On August 19, 2009, Caster Semenya, South African track star, won a gold medal in the women’s 800-meter event. According to media reports, on the same day, the International Association of Athletics Federations (IAAF) ordered Semenya to undergo gender verification testing. This article critically assesses the main concepts and claims that undergird international sport organizations' policies regarding “gender verification” or “sex testing.” We examine the ways in which these policies operate through several highly contested assumptions, including that (a) sex exists as a binary; (b) sport is a level playing field for competitors; and © some intersex athletes have an unfair advantage over women who are not intersex and, as such, they should be banned from competition to ensure that sport is a level playing field. To conclude, we make three recommendations that are consistent with the attainment of sex and gender justice in sport, which include acknowledging that myriad physical advantages are accepted in sport, recognizing that sport as a level playing field is a myth, and eliminating sex testing in sport.

Concepts: Gender, International Association of Athletics Federations, 2009 World Championships in Athletics – Women's 800 metres