Spanish Study Shows Relative Age Effect Present For Younger Swimmers

recent study conducted in Spain has taken a deep dive into the effect of relative age in swimming – that is, if an athlete is born in January or February, are their results significantly better than those born in the latter half of that same year?

The research was conducted by Sofía Martín-Consuegra Linares and Emili Rodríguez Rosales, students and swimmers at SEK International School El Castillo in Spain, looking at the top 100 performances per age group in Spain and analyzing the results based on if the athlete was born in the first, second, third or fourth trimester.

The results found that the relative age effect had its most significant impact in younger swimmers for female athletes (aged 12-14), particularly in freestyle and butterfly. The 100 fly proved to have the most statistically significant results, while the 100 breaststroke had the least, though overall, all ages and events showed swimmers born in the year’s first trimester were faster on average than those born in the last.

For male swimmers, where 13 was the youngest age studied, the results show once again younger swimmers are more affected (13-14 year-olds). The 100 free and 100 fly differences were statistically significant up until the age of 14, while in the 100 breast, performance improvements from those born earlier in the year was sustained up until the age of 18.

In general, the results show that swimmers born in the first and second trimesters have better (faster) average performances than those born in the third and fourth. With over 14,000 pieces of data for each gender, the male results were more significant, though the relative age effect existed for both genders.

The study hopes that by shedding light on these facts, meets will continue to designate age groups based on a swimmer’s age on the first day of the meet compared to their age at year’s end, for example, to level the playing field as much as possible.

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About James Sutherland

James Sutherland

James swam five years at Laurentian University in Sudbury, Ontario, specializing in the 200 free, back and IM. He finished up his collegiate swimming career in 2018, graduating with a bachelor's degree in economics. In 2019 he completed his graduate degree in sports journalism. Prior to going to Laurentian, James swam …

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