The frequency and performance trends of European countries in the U18 and U20 rankings for 1500 m and 3000 m between 2009-2020.

We purpose to determine the nationality of the European middle-distance athletes under 18 years (U18) and under 20 years (U20) during the last decade, to verify the participation trend for each country, and to assess whether the place of competition can be associated with the athletes ranking position. The sample comprised 902 European male runners, ranked among the best finishers from 2009 to 2020. The athletes were divided into two categories ( ​= ​266; and  ​= ​636) of two distances ( ​= ​397;  ​= ​505). The Mantel test was used for participation trend and the Chi-square test () was used to verify differences between the ranking position and the place of competition. For both distances, the highest number of athletes were from Spain ( 127), followed by Turkey ( 62) and Great Britain ( 50). No significant trends were shown for most of the countries, in both distances. A positive trend was shown for Slovenia (i.e., 3000 ​m) over the years. A non-significant association was verified between the countries and the ranking position, as non-significant differences were proved for the place of competition. This information may be useful to guide athlete development programs in each country.