Sex Differences in Upper‐ and Lower‐Limb Muscle Strength in Children and Adolescents: A Meta‐Analysis

European Journal of Sport Science, Journal Year: 2025, Volume and Issue: 25(5)

Published: April 5, 2025

ABSTRACT On average, adult men are physically stronger than women. The magnitude of this difference depends on the muscle tested, with larger sex differences observed in upper‐ lower‐limb muscles. Whether body region‐specific strength exist children is unclear. purpose current meta‐analysis was to determine whether and adolescents differ between Data were extracted from studies participants aged ≤ 17 years who completed tests maximal isometric or isokinetic upper‐limb muscles (e.g., elbow flexors extensors) knee extensors ankle dorsiflexors). Participants partitioned into three age groups: 5–10 old, 11–13 14–17 old. analysis included 299 effects 34 studies. total sample 6634 (3497 boys 3137 girls). Effect sizes g = 0.65 (95% confidence intervals (CI) [0.46, 0.84]) 0.34 CI [0.19, 0.50]) 5–10‐year‐olds; 0.73 [0.56, 0.91]) 0.43 [0.27, 0.59]) 11–13‐year olds; 1.84 [1.64, 2.03]) 1.18 [1.00, 1.37]) 14–17‐year‐olds. Upper‐ 17% 8% greater girls when 18% 10% 50% 30% Thus, average. This exists before puberty, increases markedly male more pronounced throughout development.

Language: Английский

Reply to Williams et al.: Fair and Safe Eligibility Criteria for Women's Sport

Scandinavian Journal of Medicine and Science in Sports, Journal Year: 2024, Volume and Issue: 34(11)

Published: Nov. 1, 2024

We thank Williams and colleagues [1] for recent comments reiterating our concerns about targeted sex verification based on allegation suspicion, which motivated initial submission [2]. It was intended as a first proposal more ethical equitable regulation of eligibility women's sport, we welcome the confirmation that several et al. authors concur International Olympic Committee's (IOC's) Framework does not protect fairness female athletes. In Lundberg [3], (including from al.) explained developmental androgenization, driven by testes-derived testosterone, underpins male athletic advantage, necessitating sex-based categories in sport. further argued IOC's "no presumption advantage" [4] is logically flawed exclusion presumed performance advantage should be default position. thus follows athletes with these XY DSDs hold advantages. Since many commentary have acknowledged advantages result androgenization feature certain [7], justifies ineligibility protected category al.'s rejection unjustified scientific grounds contradictory. inappropriately "straw man" position to criticize an assumed screening minors. Our advocate this, nor do set target age. Rather, believe occur early enough athlete's career their privacy dignity avoid failures past [8]. Furthermore, overlook reality procedures are already used sports but routinely applied ad hoc manner lacks standardization suspicion. Notably, World Aquatics introduced cohort-wide requirement certify chromosomal meet international eligibility. not, then, proposing novelty, arguing approach improves treatment all Maintaining status quo enables problems seen persist will continue significant harm propose atypical screen results prompt immediate referral clinical specialists, who typically conduct extensive anatomical, genetic, endocrinological tests within established medical workflows secure diagnosis [9]. As this "standard care" beyond remit federations, it specialists must address challenges delivering "invasive" "potentially humiliating" care. final point ethics, also misleading characterization coercive offer. Were true, would rule out or doping any kind. raise costly impractical. However, technological advances mean simple inexpensive, require minimal equipment could completed under 60 min. Implementation stratified phased appropriately spread cost, has been done anti-doping programs. noted [2], supported 82% [8], ultimately, sport organizations duty respect internationally recognized human rights girls women equality non-discrimination basis [10]. look forward constructive discourse between scientists, associations, other key stakeholders topic, including proposals alternative approaches integrity broader process follow-up examinations rare cases scientifically sound, ethically justifiable operationally feasible. The nothing report. like make joint conflict interest statement they declare following: Several received payment provide expert testimony related topic. consultancy work and/or companies. travel accommodation expenses speaking engagements spoken mainstream media Three (E.N.H., C.D., J.P.) unpaid advisors advocacy organizations.

Language: Английский

Author’s response to “letter to the editor comment on: ‘A unique pseudo-eligibility analysis of longitudinal laboratory performance Data from a transgender female competitive cyclist’” by Lundberg, O’Connor, Kirk, Pollock, and Brown

Deleted Journal, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 28, 2024

Longitudinal Laboratory Performance Data from a Transgender Female Competitive Cyclist [3]".While this critique presents itself as scientific, it seems to be driven more by subjective opinion for the reasons we set out below. TerminologyRegarding authors' key argument that sex is binary, important note idea widely disputed in modern scientific literature.For example, King [4] has stated not simple binary concept, citing numerous chromosomal variations and biological complexities contribute athletes with variation classification.Fausto-Sterling [5] Massa [6] further emphasise may understood spectrum.By considering these perspectives, authors of letter present one-sided could mislead readers overlook nuances needed balanced debate on topic.In title our cycling paper [3], [1] claims terminology used confusing, particularly distinction between "transgender female" woman."However, confusing readers, nor unclear itself.The clearly states pseudo-eligibility analysis transgender female cyclist, competing at elite or grassroots levels.'Female' 'woman' are often interchangeably, extended discussion language adds little value critique.We, also disprove suggestion use negative such "trans-identifying male [1]", represents misgendering people can cause harm [7]. Regarding comparison groupsThe opportunity address concerns raised regarding groups previous work [2] utilised sub-elite woman cyclist [3] appreciated.To clarify, all cisgender

Language: Английский