Effects on Cardiac Dimensions and Peak Oxygen Uptake After Long-Term Deconditioning in Elite Athletes

This longitudinal observational study aimed to determine if ventricular dimensions of the athlete's heart remain balanced and proportional to peak oxygen uptake (VO₂peak) following long-term deconditioning in elite athletes. Fourteen mixed-type male athletes (7 soccer, 7 handball players) were prospectively evaluated with cardiac magnetic resonance imaging and cardiopulmonary exercise testing while active at elite level and after retirement. Athletes were cross-sectionally compared to 14 age-matched controls at baseline and follow-up. Statistical analysis was performed using nonparametric tests. Descriptive statistics are presented as median [Q1, Q3]. Since baseline, athletes reported continued elite sports for 5 [2, 9] years followed by retirement for 12 [7, 14] years. Left ventricular end-diastolic volume (LVEDV) decreased by 17% (261 mL to 222 mL, p < 0.001). Right ventricular end-diastolic volume (RVEDV) decreased by 14% (266 mL to 232 mL, p < 0.001). Left atrial end-systolic volume decreased by 16% (94 mL to 82 mL, p < 0.05). Peak oxygen uptake (VO₂peak) decreased by 17% (3.96 L/min to 3.37 L/min, p < 0.001). There were no differences between athletes after retirement compared to controls. LVEDV and RVEDV were balanced in athletes at baseline (r_s = 0.92, p < 0.001) and follow-up (r_s = 0.92, p < 0.001). LVEDV and RVEDV indexed to VO₂peak remained unchanged after deconditioning. Exercise-induced cardiac remodeling was reversible after long-term deconditioning in this cohort of elite athletes. LVEDV and RVEDV decreased and remained balanced and proportional to VO₂peak. This study indicates that cardiac adaptations to sports are physiological. However, more research is needed to investigate the reversibility of exercise-induced cardiac remodeling in disciplines with higher demands on endurance performance.