Comparison Of Running Economy Between Straight-line Running And Running With Change Of Direction In Collegiate Males

Abstract

Running economy (RE) is one of the important indicators for evaluating endurance. However, treadmill running (TR) test, seems not to be specific enough for team sport, considering their running characteristics with change of direction. PURPOSE: To investigate the RE of TR and 20m-shuttle running (SR). METHODS: 18 physically-active collegiate man (22.4 ± 2.4yrs, 177.4 ± 7.5cm, 69.3 ± 8.2kg, VO2max: 48.9 ± 6.2 ml/kg/min, training experience: 4.6 ± 1.6yrs) volunteered to participate in one increamental TR (8, 10, 12 and 14km/h) and one increamental SR (6, 8, 10 and 12km/h), with the duration of 5 min for each step, and the interval of 1 min between each 2 steps. The VO2max was also assessed in combination with the TR test. The portable gas metabolism system (K4b2, Cosmed, Italy) was used to measure the breathing gas during running. The RE for each speed was calculated as the averaged VO2 of the last 1 min during each step. RESULTS: At the same running speed (8, 10 and 12km/h), the RE of the SR are lower (oxygen consumption is higher ) than the TR (34 ± 3.6 vs. 32.5 ± 4.9 ml/kg/min, 47.9 ± 5 vs. 37.9 ± 5.9 ml/kg/min, 54.9 ± 6.2 vs. 42.0 ± 7 ml/kg/min), with the difference significant at the two higher speed (p<0.05). CONCLUSIONS: At the same running speed, the RE of SR is lower than that of TR. Assessment of RE with TR might overestimate the RE in running with change of direction. Running test with change of direction (e.g. SR) is recommended for examining the RE in team sport players.