抄録
Anaerobic and aerobic capacities are needed to enhance the performance of 400-m runners. We previously demonstrated that a 7-day hypoxic training consisting of high-intensity interval training and endurance training at submaximal load improved the exercise performance (time to exhaustion) as well as anaerobic and aerobic capacities of female 400-m runners. Time to exhaustion and capacities in a shorter training period could be beneficial for several athletes, but this has not been examined. Therefore, the purpose of this study was to investigate whether a 5-day of hypoxic training would improve duration time (time to exhaustion) and the anaerobic and aerobic capacities of elite female 400-m runners. Seven elite female 400-m runners (Personal Best time: 53.9±1.2 s) were trained for 5 days (6 sessions). Anaerobic and aerobic capacity tests were performed on the treadmill before (Pre) and after (Post) the intervention. The indices of anaerobic capacity were maximal accumulated oxygen deficit (MAOD) and maximal blood lactate concentration (Lamax). The index of aerobic capacity was the maximal oxygen uptake (VO2max). All subjects were trained in a normobaric hypoxic room (FIO2=14.4%). The training consisted of high-intensity interval training (five 30-s all-out pedaling) and endurance training (30-min incremental running and 30-min steady pedaling). After the intervention, duration time significantly increased in both anaerobic (Pre: 131±11 sec, Post: 149±15 sec, p = 0.02) and aerobic (Pre: 5.2±1.2 min, Post: 6.0±1.2 min, p < 0.01) tests. MAOD tended to increase (Pre: 54.9±6.3 ml/kg, Post: 58.4±6.8 ml/kg, p = 0.05) while the Lamax significantly increased (Pre: 19.5±3.3 mmol/l, Post: 21.5±2.6 mmol/l, p = 0.04). On the other hand, the VO2max (Pre: 51.4±5.3 ml/kg/min, Post: 53.1±5.0 ml/kg/min) did not significantly change. This study suggests that 5-days of hypoxic training was effective for enhancing duration time of anaerobic and aerobic tests, and also anaerobic capacity in well-trained female 400-m runners.
