The influence of pacing strategy on marathon world records.

The aim of this study was to analyse the influence of the pacing strategy adopted by elite marathon runners when setting every marathon world record in the last 50 years. We divided former marathon record holders into two groups: classic athletes (record holders between 1967 and 1988) and contemporaneous athletes (record holders between 1988 and 2018). The total distance of the marathon was divided into 8 sections of 5 km and 1 last section of 2.195 km, and the relative average speed of each section was calculated individually. On average athletes were slightly faster in the first half-marathon than in the second one, where they slowed down progressively (ES = 0.28, small effect). However, when comparing classic vs. contemporaneous athletes, we observed that classic athletes started significantly faster (p < .05, ES = 1.16, moderate effect), although after 25 km, their speed dropped dramatically and was significantly slower than in their contemporaneous counterparts (ES = 2.41, very large effect). This study shows that the pacing strategies of the best marathon runners in the world have changed over the last 50 years. Although a negative pace distribution has been proposed as the most efficient option, a pacing strategy characterised by very little speed changes across the whole race may be the way to go in the future.