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1.
Br J Sports Med ; 58(11): 586-597, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38599680

RESUMEN

OBJECTIVE: The primary objective of this cross-sectional study was to compare standard laboratory performance metrics of transgender athletes to cisgender athletes. METHODS: 19 cisgender men (CM) (mean±SD, age: 37±9 years), 12 transgender men (TM) (age: 34±7 years), 23 transgender women (TW) (age: 34±10 years) and 21 cisgender women (CW) (age: 30±9 years) underwent a series of standard laboratory performance tests, including body composition, lung function, cardiopulmonary exercise testing, strength and lower body power. Haemoglobin concentration in capillary blood and testosterone and oestradiol in serum were also measured. RESULTS: In this cohort of athletes, TW had similar testosterone concentration (TW 0.7±0.5 nmol/L, CW 0.9±0.4 nmol/), higher oestrogen (TW 742.4±801.9 pmol/L, CW 336.0±266.3 pmol/L, p=0.045), higher absolute handgrip strength (TW 40.7±6.8 kg, CW 34.2±3.7 kg, p=0.01), lower forced expiratory volume in 1 s:forced vital capacity ratio (TW 0.83±0.07, CW 0.88±0.04, p=0.04), lower relative jump height (TW 0.7±0.2 cm/kg; CW 1.0±0.2 cm/kg, p<0.001) and lower relative V̇O2max (TW 45.1±13.3 mL/kg/min/, CW 54.1±6.0 mL/kg/min, p<0.001) compared with CW athletes. TM had similar testosterone concentration (TM 20.5±5.8 nmol/L, CM 24.8±12.3 nmol/L), lower absolute hand grip strength (TM 38.8±7.5 kg, CM 45.7±6.9 kg, p=0.03) and lower absolute V̇O2max (TM 3635±644 mL/min, CM 4467±641 mL/min p=0.002) than CM. CONCLUSION: While longitudinal transitioning studies of transgender athletes are urgently needed, these results should caution against precautionary bans and sport eligibility exclusions that are not based on sport-specific (or sport-relevant) research.


Asunto(s)
Atletas , Estradiol , Prueba de Esfuerzo , Testosterona , Personas Transgénero , Humanos , Estudios Transversales , Masculino , Testosterona/sangre , Femenino , Adulto , Estradiol/sangre , Fuerza de la Mano/fisiología , Fuerza Muscular/fisiología , Adulto Joven , Composición Corporal/fisiología , Capacidad Vital/fisiología , Persona de Mediana Edad , Consumo de Oxígeno/fisiología , Volumen Espiratorio Forzado/fisiología
2.
Clin J Sport Med ; 33(5): e115-e122, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35533133

RESUMEN

OBJECTIVE: It remains unknown whether myonuclei remain elevated post anabolic-androgenic steroid (AAS) usage in humans. Limited data exist on AAS-induced changes in gene expression. DESIGN: Cross-sectional/longitudinal. SETTING: University. PARTICIPANTS: Fifty-six men aged 20 to 42 years. INDEPENDENT VARIABLES: Non-resistance-trained (C) or resistance-trained (RT), RT currently using AAS (RT-AS), of which if AAS usage ceased for ≥18 weeks resampled as Returning Participants (RP) or RT previously using AAS (PREV). MAIN OUTCOME MEASURES: Myonuclei per fiber and cross-sectional area (CSA) of trapezius muscle fibers. RESULTS: There were no significant differences between C (n = 5), RT (n = 15), RT-AS (n = 17), and PREV (n = 6) for myonuclei per fiber. Three of 5 returning participants (RP1-3) were biopsied twice. Before visit 1, RP1 ceased AAS usage 34 weeks before, RP2 and RP3 ceased AAS usage ≤2 weeks before, and all had 28 weeks between visits. Fiber CSA decreased for RP1 and RP2 between visits (7566 vs 6629 µm 2 ; 7854 vs 5677 µm 2 ) while myonuclei per fiber remained similar (3.5 vs 3.4; 2.5 vs 2.6). Respectively, these values increased for RP3 between visits (7167 vs 7889 µm 2 ; 2.6 vs 3.3). CONCLUSIONS: This cohort of past AAS users did not have elevated myonuclei per fiber values, unlike previous research, but reported AAS usage was much lower. Training and AAS usage history also varied widely among participants. Comparable myonuclei per fiber numbers despite decrements in fiber CSA postexposure adheres with the muscle memory mechanism, but there is variation in usage relative to sampling date and low numbers of returning participants.


Asunto(s)
Anabolizantes , Esteroides Anabólicos Androgénicos , Masculino , Humanos , Andrógenos/efectos adversos , Anabolizantes/efectos adversos , Músculos , Expresión Génica
3.
Calcif Tissue Int ; 110(1): 41-56, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34382100

RESUMEN

The aim of this systematic review and meta-analysis was to provide an updated analysis, including the use of more robust methods, on the effects of exercise on bone mineral density in men. Randomised Control Trials of > 24 weeks and published in English up to 01/05/20 were retrieved from 3 electronic databases, cross-referencing, and expert review. The primary outcome measures were changes in FN, LS, and lower limb BMD Standardised effect sizes were calculated from each study and pooled using the inverse heterogeneity model. A statistically significant benefit of exercise was observed on FN BMD [g = 0.21 (0.03, 0.40), Z = 2.23 p = 0.03], with no observed statistically significant benefit of exercise on LS BMD [g = 0.10 (- 0.07, 0.26), Z = 1.15 p = 0.25]. This analysis provided additional evidence to recommend ground- and/or joint-reaction force exercises for improving or maintaining FN, but not LS BMD. Additional well-designed RCTs are unlikely to alter this evidence, although interventions that include activities that directly load the lumbar spine are needed to ensure this is not a potential method of improving LS BMD.


Asunto(s)
Densidad Ósea , Ejercicio Físico , Humanos , Vértebras Lumbares , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto
4.
BMC Med Genomics ; 16(1): 94, 2023 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-37138349

RESUMEN

BACKGROUND: The effects of Anabolic Androgenic Steroids (AAS) are largely illustrated through Androgen Receptor induced gene transcription, yet RNA-Seq has yet to be conducted on human whole blood and skeletal muscle. Investigating the transcriptional signature of AAS in blood may aid AAS detection and in muscle further understanding of AAS induced hypertrophy. METHODS: Males aged 20-42 were recruited and sampled once: sedentary controls (C), resistance trained lifters (RT) and resistance trained current AAS users (RT-AS) who ceased exposure ≤ 2 or ≥ 10 weeks prior to sampling. RT-AS were sampled twice as Returning Participants (RP) if AAS usage ceased for ≥ 18 weeks. RNA was extracted from whole blood and trapezius muscle samples. RNA libraries were sequenced twice, for validation purposes, on the DNBSEQ-G400RS with either standard or CoolMPS PE100 reagents following MGI protocols. Genes were considered differentially expressed with FDR < 0.05 and a 1.2- fold change. RESULTS: Cross-comparison of both standard reagent whole blood (N = 55: C = 7, RT = 20, RT-AS ≤ 2 = 14, RT-AS ≥ 10 = 10, RP = 4; N = 46: C = 6, RT = 17, RT-AS ≤ 2 = 12, RT-AS ≥ 10 = 8, RP = 3) sequencing datasets, showed that no genes or gene sets/pathways were differentially expressed between time points for RP or between group comparisons of RT-AS ≤ 2 vs. C, RT, or RT-AS ≥ 10. Cross-comparison of both muscle (N = 51, C = 5, RT = 17, RT-AS ≤ 2 = 15, RT-AS ≥ 10 = 11, RP = 3) sequencing (one standard & one CoolMPS reagent) datasets, showed one gene, CHRDL1, which has atrophying potential, was upregulated in RP visit two. In both muscle sequencing datasets, nine differentially expressed genes, overlapped with RT-AS ≤ 2 vs. RT and RT-AS ≤ 2 vs. C, but were not differentially expressed with RT vs. C, possibly suggesting they are from acute doping alone. No genes seemed to be differentially expressed in muscle after the long-term cessation of AAS, whereas a previous study found long term proteomic changes. CONCLUSION: A whole blood transcriptional signature of AAS doping was not identified. However, RNA-Seq of muscle has identified numerous differentially expressed genes with known impacts on hypertrophic processes that may further our understanding on AAS induced hypertrophy. Differences in training regimens in participant groupings may have influenced results. Future studies should focus on longitudinal sampling pre, during and post-AAS exposure to better control for confounding variables.


Asunto(s)
Anabolizantes , Esteroides Anabólicos Androgénicos , Masculino , Humanos , Anabolizantes/farmacología , Transcriptoma , Proteómica , RNA-Seq , Congéneres de la Testosterona/efectos adversos , Músculo Esquelético/fisiología
5.
BMJ Open Sport Exerc Med ; 8(1): e001273, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35127133

RESUMEN

The IOC recently published its framework on fairness, inclusion and non-discrimination based on gender identity and sex variations. This framework is drafted mainly from a human rights perspective, with less consideration for medical/scientific issues. The framework places the onus for gender eligibility and classification entirely on the International Federations (IFs), even though most will not have the capacity to implement the framework. The position of no presumption of advantage is contrary to the 2015 IOC consensus. Implementation of the 2021 framework will be a major challenge for IFs that have already recognised the inclusion of trans and women athletes with differences of sexual development (DSD) using a scientific/medical solution. The potential consequences for sports that need to prioritise fairness or safety could be one of two extremes (1) exclusion of all transgender or DSD athletes on the grounds of advantage or (2) self-identification that essentially equates to no eligibility rules. Exclusion of all transgender or DSD athletes is contrary to the Olympic charter and unlawful in many countries. While having no gender eligibility rules, sport loses its meaning and near-universal support. Athletes should not be under pressure to undergo medical procedures or treatment to meet eligibility criteria. However, if an athlete is fully informed and consents, then it is their free choice to undergo carefully considered or necessary interventions for gender classification for sport to compete fairly and safely in their chosen gender. Free choice is a fundamental human right, but so is the right to fair and safe competition.

6.
Eur J Sport Sci ; 21(11): 1500-1509, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34077312

RESUMEN

The inclusion of transwomen into elite female sport has been brought into question recently with World Rugby banning transwomen from the elite female competition, aiming to prioritise safety over fairness and inclusion, citing the size, force and power-producing advantages conferred to transwomen. The same question is being asked of all Olympic sports including non-contact sports such as archery and shooting. As both these Olympic sports are the polar opposite to the contact sport of rugby in terms of the need to consider the safety of athletes, the IF of both archery and shooting should consider the other elements when deciding the integration of trans individuals in their sports. Studies on non-athletic transwomen have reported muscle mass and strength loss in the range of 5-10% after 1 year of their transition, with these differences no longer apparent after 2 years. Therefore, based on the current scientific literature, it would be justified for meaningful competition and to prioritise fairness, that transwomen be permitted to compete in elite archery after 2 years of GAT. Similarly, it would be justified in terms of shooting to prioritise inclusion and allow transwomen after 1 year of GAT given that the only negligible advantage that transwomen may have is superior visuospatial coordination. The impact of this considered integration of transwomen in elite sports such as archery and shooting could be monitored and lessons learned for other sports, especially where there are no safety concerns from contact with an opponent.


Asunto(s)
Atletas , Rendimiento Atlético/ética , Rendimiento Atlético/fisiología , Deportes/ética , Deportes/fisiología , Personas Transgénero , Toma de Decisiones , Femenino , Humanos , Masculino , Factores Sexuales , Procedimientos de Reasignación de Sexo
7.
Sports Med ; 51(10): 2221-2229, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33835351

RESUMEN

INTRODUCTION: Since 2004, the International Olympic Committee (IOC) store all samples collected at summer Olympic Games (OG) for retrospective re-analysis with more advanced analytical techniques to catch doping athletes. METHODS: All announced Anti-Doping Rule Violations (ADRVs) from IOC re-tests of the 2004, 2008 and 2012 OG (via IOC, International Federations and Athletics Integrity Unit public data) and other ADRVs confirmed to impact OG results from 1968 to 2012 (via the list of Doping Irregularities on olympedia.org) were collated to investigate how many medals have been impacted by ADRVs, when the ADRV was identified relative to the OG in question and its cause. RESULTS: One hundred and thirty-four medals were impacted by ADRVs but only 26% of these ADRVs were identified at the time of the OG. Most ADRVs impacting medal results (74%) were identified retrospectively, either from events prior to the OG (17%) or via IOC re-tests of samples from 2004, 2008 and 2012 (57%). ADRVs impacting medal results from these re-tests took a mean of 6.8 ± 2.0 years to be announced relative to the end of the OG in which the medal was originally won. Exogenous Anabolic Androgenic Steroid metabolites were present in 90% of all athlete (n = 142) samples from IOC re-tests with dehydrochloromethyltestosterone and stanozolol accounting for 79% of detected substances. Athletics (n = 64) and weightlifting (n = 62) were the most affected sports. CONCLUSION: This analysis shows the frequency of targeted pre-OG Out-of-Competition testing should increase. We advocate for long-term sample storage to continue and additionally incorporate novel and potentially complementary technologies/sample matrices.


Asunto(s)
Distinciones y Premios , Doping en los Deportes , Deportes , Atletas , Humanos , Estudios Retrospectivos
8.
J Sports Med Phys Fitness ; 61(8): 1173-1183, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34256541

RESUMEN

The coronavirus disease (COVID-19) pandemic has had an unprecedent impact on the world of sport and society at large. Many of the challenges with respect to integrity previously facing competitive sport have been accentuated further during the pandemic. Threats to the integrity of sporting competition include traditional doping, issues of technological fairness, and integration of transgender and intersex athletes in elite sport. The enforced lull in competitive sport provides an unprecedented opportunity for stakeholders in sport to focus on unresolved integrity issues and develop and implement long-lasting solutions. There needs to be a concerted effort to focus on the many technological innovations accelerated by and perfected during COVID-19 that have enabled us to work from home, such as teaching students on-line, applications for medical advice, prescriptions and referrals, and treating patients in hospitals/care homes via video links and use these developments and innovations to enhance sport integrity and anti-doping procedures. Positive sports integrity actions will require a considered application of all such technology, as well as the inclusion of "omics" technology, big data, bioinformatics and machine learning/artificial intelligence approaches to modernize sport. Applications include protecting the health of athletes, considered non-discriminative integration of athletes into elite sport, intelligent remote testing to improve the frequency of anti-doping tests, detection windows, and the potential combination with omics technology to improve the tests' sensitivity and specificity in order to protect clean athletes and deter doping practices.


Asunto(s)
COVID-19 , Doping en los Deportes , Inteligencia Artificial , Atletas , Humanos , Pandemias , SARS-CoV-2
9.
Sports Med ; 51(7): 1401-1415, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33761127

RESUMEN

Sport is historically designated by the binary categorization of male and female that conflicts with modern society. Sport's governing bodies should consider reviewing rules determining the eligibility of athletes in the female category as there may be lasting advantages of previously high testosterone concentrations for transwomen athletes and currently high testosterone concentrations in differences in sex development (DSD) athletes. The use of serum testosterone concentrations to regulate the inclusion of such athletes into the elite female category is currently the objective biomarker that is supported by most available scientific literature, but it has limitations due to the lack of sports performance data before, during or after testosterone suppression. Innovative research studies are needed to identify other biomarkers of testosterone sensitivity/responsiveness, including molecular tools to determine the functional status of androgen receptors. The scientific community also needs to conduct longitudinal studies with specific control groups to generate the biological and sports performance data for individual sports to inform the fair inclusion or exclusion of these athletes. Eligibility of each athlete to a sport-specific policy needs to be based on peer-reviewed scientific evidence made available to policymakers from all scientific communities. However, even the most evidence-based regulations are unlikely to eliminate all differences in performance between cisgender women with and without DSD and transwomen athletes. Any remaining advantage held by transwomen or DSD women could be considered as part of the athlete's unique makeup.


Asunto(s)
Atletas , Rendimiento Atlético , Consenso , Femenino , Humanos , Masculino , Desarrollo Sexual , Testosterona
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