The 12-Lead Electrocardiogram of the Rugby Football League Athlete: Impact of Sex and Age.

Electrocardiogram (ECG) findings in male Rugby Football League (RFL) athletes have previously been investigated but variations in other demographics are less understood. The study examined 161 ECGs in male and female, paediatric (< 18 years old) and adult (≥ 18 years old) RFL athletes. Athletes (65% male, 35% female) aged 14-33 years underwent a 12-lead ECG that was assessed for training-related cardiac electrical adaptations. Four athletes with abnormal ECGs were excluded. Results indicated that male athletes had an increased PR interval (152 ± 32 vs. 140 ± 19 ms; p < 0.001), QRS duration (98 ± 7 vs. 87 ± 6 ms; p < 0.001), voltage criteria for right (6 ± 3 vs. 4 ± 2 mm; p < 0.001) and left (33 ± 9 vs. 27 ± 7 mm; p < 0.001) ventricular hypertrophy (RVH/LVH) compared to females, who exhibited increased resting heart rate (HR) (67 ± 11 vs. 62 ± 11 bpm; p < 0.001) and QTc intervals (408 ± 45 vs. 398 ± 22 ms; p = 0.028). Adult athletes had a reduced HR (61 ± 10 vs. 66 ± 13 bpm; p < 0.001) and RVH criteria (5 ± 2 vs. 7 ± 3 mm; p = 0.015) compared to paediatric athletes. When controlling for weekly training hours in adult athletes, males present only a longer PR interval (156 ± 32 vs. 141 ± 19 ms; p < 0.037) and QRS duration (99 ± 7 vs. 87 ± 7 ms; p < 0.001) when compared to females. These results highlight the need for tailored cardiac screening guidelines that account for an RFL athlete's sex, age and training exposure.