This study examined the effects of (1) an intermittent training using a mechanically braked cycle ergometer and (2) resistance training using free weight on the maximal oxygen deficit and VO₂max. For the first 6 weeks, six subjects trained using an intermittent training protocol five days per week. The exhaustive intermittent training consisted of seven to eight sets of 20 s exercise at anintensity of about 170% of VO₂max with a 10 s rest between each bout. After the training, the maximal oxygen deficit increased significantly from 64.3±5.0 ml⋅kg^-1 to 75.1±5.7 ml⋅kg^-1 (p<0.01), while VO₂max increased from 52.0±2.7 ml⋅kg^-1⋅min^-1 to 57.6±2.9 ml⋅kg^-1⋅min^-1 (p<0.05) . For the following 6 weeks, the subjects used the same intermittent training for 3 days per week and a resistance training for the other 3 days per week. The resistance training consisted of (1) 4 sets of 12 bouts of squat and leg curl exercise at 12 repetition maximum (RM) . (2) 2 sets of maximal bouts of the same exercise with a load of 90%, 80%, and 70% of 1 RM. After the training period, the maximal oxygen deficit increased further to the value of 86.8±5.9 ml⋅kg^-1which was significantly higher than the value attained at the end of the intermittent training. On the other hand, VO₂max did not increase significantly from the value observed at the end of the 6 weeks of intermittent training. Body weight was not significantly changed throughout the 12-week training period. Maximal circumference of the thigh did not changed during the first 6-week of the intermittent training period (pre-training: 57.1±1.2 cm, after 6-week training: 57.3±1.1 cm), while it increased significantly after the last 6-week combined training (59.0±0.8 cm, p<0.05) . In conclusion, this study showed that (1) high intensity intermittent training improves both the anaerobic and aerobic energy supplying systems, (2) additional resistance training with the intermittent training further increases the anaerobic energy supplying system, probably through increased muscle mass.