The Running Efficiency of Ultramarathon Runners

Abstract

It revealed that kinematics and physiological factors such as maximal oxygen uptake (VO2max), running economy (RE), biomechanical parameters and fractional utilization of maximal oxygen uptake (%VO2max) effect the ultramarathon runners' running performance (URRP). Therefore, it is necessary to investigate the running efficiency, the kinematics and physiological efficiency of the ultramarathon runners (UR) to improve the URRP. PURPOSE: To investigate if the URs with better performance have higher kinematics and physiological efficiency. METHODS: Ten runners in 12-hour race of the 2007 Taipei international ultramarathon competition were recruited in this study. Five of them with the record higher than 96.2km are classified as high performance group (HPG), and the other fives as low performance group (LPG). They performed a treadmill running test with O2 & CO2 gas analysis recording. The running speeds changed every 5 minutes at 6, 8, 9, 10, 12 and 14 km/hr. A mini wireless 3D accelerometer was put on each runner to collect 3 axis acceleratory velocities, step frequency, step lengths and running stages during the test. RESULTS: This study showed (1) the significant correlation between performance and kinematic variables in sum of the vectors(r=-0.7572), percentage of VO2max at 8 km/hr(r=-0.6379) and running economy at mean velocity with percentage of VO2max (RE%VO2max) (r=0.6911), (2) the RE%VO2max with minor discrepancy between HPG and LPG (t=1.84), (3) the %VO2max at 8, 9, 10km/hr with minor discrepancy between HPG and LPG (t=-1.61,-1.82,-1.78), and (4) the performance significantly related to XYZ8 by the standard regression analysis (R2=0.5734; P<0.05). CONCLUSION: The HPG URs have higher kinematics and physiological efficiency than LPG URs.