男子陸上長距離選手の持久走時における走行位置の違いが心拍数、血中乳酸濃度及び運動学的変数に及ぼす影響

抄録

Few studies have been conducted on the effects of drafting in long distance running under actual competition conditions, such as on a track. Therefore, the purpose of this study was to investigate the differences in physiological demands at the same pace between running alone and in formations on the track in male long-distance runners. Nine well trained male collegiate long-distance runners participated in this study (age, 19.9±0.8 years; height, 170.0±5.3 cm; weight, 57.8±4.2 kg; competition career, 7.9±2.6 years). A 5,000 m constant pace run at a running speed equivalent to 80%VO_2max, obtained from incremental testing in the laboratory beforehand, was performed in four positions: at the top, middle, and tail running in formations and a solo-running. The primary findings of this study indicate that the average heart rate during middle-position running was significantly lower compared to solo running (168±10.2 vs. 174.4±9.9 beat/min), and that blood lactate concentrations were significantly lower when running in the middle and at the tail compared to running solo and top (5.6±2.2, 5.6±0.7 vs. 8.6±2.1, 9.5±2.9 mmol/L, respectively, P<0.05). Furthermore, it was observed that running in the middle position was associated with a significantly shorter stride length (1.65±0.08 vs. 1.71±0.08 m/step) and a significantly higher stride frequency (188.2±9.1 vs. 181.1±6.5 step/min) compared to running solo (each P<0.05). These results suggest that when running in a column formation with three runners, physiological demands may be reduced by the presence of a runner ahead, and there is a potential advantage to running in the middle position.