Sex-specific differences in myocardial tissue characteristics among professional athletes: a systematic review and meta-analysis

Introduction Emerging evidence suggests that male and female athletes may exhibit different cardiac adaptation patterns, potentially due to hormonal influences, body composition, and training responses. However, determining clear sex-specific differences in cardiac magnetic resonance (CMR) parameters such as late gadolinium enhancement (LGE), extracellular volume (ECV), and native T1 remains challenging, as available studies are limited by small sample sizes and heterogeneity in athletic populations. Understanding these differences is important for distinguishing physiological cardiac adaptation from potential pathological remodeling in athletic populations. Purpose To systematically review and meta-analyze case-control studies evaluating sex differences in CMR myocardial tissue characteristics in professional athletes. Methods Systematic search, review, and meta-analysis according to Cochrane Collaboration Steps and MOOSE (meta-analysis of observational studies in epidemiology recommendations) of case-control studies reporting LGE, ECV, and T1 native mapping in male and female professional athletes. Results In a pooled analysis of 11 studies comprising 2,716 athletes, men showed a higher prevalence of late gadolinium enhancement (LGE) compared with women (RR 1.52, 95% CI 1.13–2.05; p = 0.006), with low-to-moderate heterogeneity (I² = 35%), (Fig. 1) Subgroup analyses revealed that men also had a higher prevalence of hinge-point LGE than women (RR 1.56, 95% CI 1.17–2.09; p = 0.003), with no observed heterogeneity across studies (I² = 0%), (Fig.1), suggesting a highly consistent sex-related difference. In a pooled random-effects analysis of 566 male and 332 female athletes, men demonstrated lower native T1 values than women (SMD −0.63, 95% CI −1.26 to −0.00; I² = 0%), indicating a moderate-to-large and highly consistent sex difference (Fig 2A). Male athletes also showed lower ECV compared with female athletes (SMD −0.76, 95% CI −1.17 to −0.35), although substantial between-study heterogeneity was observed (I² = 75%) (Fig. 2B). Conclusions Our meta-analysis demonstrates consistent and clinically relevant sex differences in CMR tissue characteristics among professional athletes. Men show a higher prevalence of LGE—particularly hinge-point LGE—as well as lower native T1 and ECV compared with women. These findings support the presence of sex-specific myocardial adaptation to intensive training. Potential mechanisms may include sex hormone–mediated modulation of myocardial remodeling, differences in ventricular wall stress distribution, and cumulative hemodynamic loading during training. Incorporating sex-specific reference frameworks in CMR interpretation in athletes may improve differentiation between physiological remodeling and pathology.