Research On The Factors Affecting The Running Economy Of Marathon Runners

Purposes:Running economy plays a key role in aerobic endurance performance.The study aimed to explore the factors that affect the running economy from two aspects:gait characteristic and oxygen uptake kinetic,providing strategies for improving running economy.Methods:Ten male marathon runners were recruited to conduct the indoor treadmill test and the outdoor field test at three intensities respectively.And recording athletes'gas metabolism variables,heart rate,blood lactate and gait characteristics.The fitting formula of the parameters of oxygen uptake kinetic during exercise was:VO₂?t?=VO₂?on?+Aon?1?e-?t-TDon?/?on?The data were analyzed by SPSS22.0 statistical software and were expressed as?3?±SD,and the significance level was P<0.05.Result:1?the stride length and ground contact time on the field running were significantly higher than those on the treadmill running,and the swing time was significantly lower than treadmill.There was no significant difference in oxygen uptake,heart beats and energy expenditures between the field and the treadmill at the three intensities.However,at 17km/h,the blood lactic acid value and the slow components and amplitude of oxygen uptake kinetics for filed running were significantly higher than treadmill running.2)As the intensity increased,the time of oxygen uptake to attain the steady state was delayed,the slow component and amplitude increased significantly.3)The time constant?of the oxygen uptake kinetic and the contact ground time at high intensity showed a significant positive correlation with running economy,and the stride length showed a significant negative correlation with running economy.Conclusion:Oxygen uptake dynamics and gait characteristics are factors affecting running economy.Faster oxygen uptake rates,shorter ground contact time,and longer stride length at high intensities are conducive to saving energy consumption.