So far, the testing methodologies of the work efficiency are not perfect, though international scholars have actively explored the energy methods for running efficiency early.OBJECTIVE:
To investigate the work efficiency of 400-meter running.METHODS:
Twelve male subjects (the first or second rank sprinter) volunteered to participate in this study, and they had no muscle damage, fractures and diseases of the circulatory and respiratory systems in the past 1 year. We recorded synchronously the related parameters using the high speed PULNIX CCD (TM6710) system, the portable CORTEX, Meta Max 3B and the self-made timepiece of measuring time in the level track. Energy expenditure was collected by the MetaMax 3B system. We calculated the work efficiency of 400-meter running using mathematics modeling and the statistical methods based on theoretical analyzing and collected datum-physiological and kinematic parameters.RESULTS AND CONCLUSION:
We obtained average velocity in the X axis [(7.00±0.23) m/s] and average displacement data in the Y axis [(10.0±1.70) cm] at the centre of the body mass. The time of movement was (57.20±1.84) seconds. The net energy consumption, the heat energy, the drag energy, the potential energy, the kinetic energy and the work efficiency were (301.2±29.3) kJ, (197.0±30.3) kJ, (5.3±0.6) kJ, (3.7±0.7) kJ, (95.2±10.9) kJ, (35.0±4.3)%, respectively. In the average speed of (7.00±0.23) m/s, it was concluded that the average work efficiency (external work efficiency) was 35% during 400-meter running in the level track. It is a viable method that combines the energy balance theory model with the means of biomechanics to measure the work efficiency of human body during exercise.