RESUMO
BACKGROUND: An extraordinary long-term running performance may benefit from low dynamic loads and a high load-bearing tolerance. An extraordinary runner (ageâ¯=â¯55 years, heightâ¯=â¯1.81 m, massâ¯=â¯92 kg) scheduled a marathon a day for 100 consecutive days. His running biomechanics and bone density were investigated to better understand successful long-term running in the master athlete. METHODS: Overground running gait analysis and bone densitometry were conducted before the marathon-a-day challenge and near its completion. The case's running biomechanics were compared pre-challenge to 31 runners who were matched by a similar foot strike pattern. RESULTS: The case's peak vertical loading rate (ΔxÌâ¯=â¯-61.9 body weight (BW)/s or -57%), peak vertical ground reaction force (ΔxÌâ¯=â¯-0.38 BW or -15%), and peak braking force (ΔxÌâ¯=â¯-0.118 BW or -31%) were remarkably lower (p < 0.05) than the control group at â¼3.3 m/s. The relatively low loading-related magnitudes were attributed to a remarkably high duty factor (0.41) at the evaluated speed. The foot strike angle of the marathoner (29.5°) was greater than that of the control group, affecting the peak vertical loading rate. Muscle powers in the lower extremity were also remarkably low in the case vs. controls: peak power of knee absorption (ΔxÌâ¯=â¯-9.16 watt/kg or -48%) and ankle generation (ΔxÌâ¯=â¯-3.17 watt/kg or -30%). The bone mineral density increased to 1.245 g/cm² (+2.98%) near completion of the challenge, whereas the force characteristics showed no statistically significant change. CONCLUSION: The remarkable pattern of the high-mileage runner may be useful in developing or evaluating load-shifting strategies in distance running.