Sex Differences In Proportional Numbers Of Top Performances Within Elite Youth Track And Field Athletes

There is a small but consistent sex difference (~5%) in track running performance in that boys outperform girls prior to puberty in elite youth track and field athletes. Whether the proportional number of males and females differ among top elite youth performances remains unknown. PURPOSE: To determine among elite youth track athletes 1) the proportional number of males vs. females and 2) at what age (between 5 and 18 years) females are no longer represented, within the overall top running performances. METHODS: Top age group running performance records of elite USA male and female track and field athletes (5-18 years) over a ten-year period (2009-2019) were collected from an online database (athletic.net). The top 10 and top 100 performances were recorded for four running events: 100 m, 200 m, 400 m, and 800 m. Data are reported in mean ± standard deviation. RESULTS: Between 5-6 years, the proportion of males (M) was greater than females (F) in the top 10 (M = 6.3 ± 1.4, range: 4-8 (# of males that placed in the top 10); F = 3.8 ± 1.4, range: 2-6 (# of females that placed in the top 10); χ2 = 10, p = 0.002) and top 100 (M = 59.4 ± 13.0, range: 30-74; F = 36.0 ± 5.4, range: 26-44; χ2 = 92, p < 0.001), across all four events. Between 7-12 years, there was a greater proportion of males than females in the top 10 (M = 8.9 ± 0.9, range: 7-10; F = 1.1 ± 0.9, range: 0-3; χ2 = 295, p < 0.001) and top 100 (M = 80.7 ± 5.5, range: 69-88; F = 19.3 ± 5.5, range: 12-31; χ2 = 1811, p < 0.001), across all four events. Additionally, between 13-18 years, there was a greater proportion of males than females in the top 10 (M = 10.0 ± 0.0, range: 10; F = 0.0 ± 0.0, range: 0) and top 100 (M = 99.5 ± 1.1, range: 96-100; F = 0.46 ± 1.10, range: 0-4; χ2 = 4712, p < 0.001), across all four events. Females were no longer represented within the top 10 overall performances starting at 13 years in the 100 m and 200 m, 12 years in the 400 m, and after 10 years in the 800 m. Females were no longer represented within the top 100 overall performances starting at 14 years in all four events. CONCLUSION: Prior to puberty in elite youth track and field athletes, there is a greater proportion of males within the top 10 and top 100 overall running performances. Between ages 5-6 years, the sex difference in the proportion of top running performances is small, but present, and increased between ages 7-12 years, with no females represented after 13 years.