This study consists of two training experiments using a mechanically braked cycle ergometer. First, the effect of 6 wk of moderate-intensity endurance training (intensity: 70% of maximal oxygen uptake (˙VO2max), 60 min·d-1, 5 d·wk-1) on the anaerobic capacity (the maximal accumulated oxygen deficit) and ˙VO2max was evaluated. After the training, the anaerobic capacity did not increase significantly(P > 0.10), while ˙VO2max increased from 53 ± 5 ml·kg-1·min-1 to 58 ± 3 ml·kg-1·min-1 (P < 0.01) (mean± SD). Second, to quantify the effect of high-intensity intermittent training on energy release, seven subjects performed an intermittent training exercise 5 d·wk-1 for 6 wk. The exhaustive intermittent training consisted of seven to eight sets of 20-s exercise at an intensity of about 170% of ˙VO2max with a 10-s rest between each bout. After the training period, ˙VO2max increased by 7 ml·kg-1·min-1, while the anaerobic capacity increased by 28%. In conclusion, this study showed that moderate-intensity aerobic training that improves the maximal aerobic power does not change anaerobic capacity and that adequate high-intensity intermittent training may improve both anaerobic and aerobic energy supplying systems significantly, probably through imposing intensive stimuli on both systems.
Department of Physiology and Biomechanics, National Institute of Fitness and Sports, Shiromizu-cho 1, Kanoya City, Kagoshima Prefecture, 891-23 JAPAN
Submitted for publication November 1994.
Accepted for publication December 1995.
The training protocol used in experiment 2 was first introduced by Kouichi Irisawa, who was a head coach of the Japanese National Speed Skating Team. The training has been used by the major members of the Japanese Speed Skating Team for several years.
Present addresses: I. Tabata, Laboratory of Exercise Physiology, Division of Health Promotion, National Institute of Health and Nutrition, 1-23-1 Toyama, Shinjuku City, Tokyo 162 Japan; Y. Hirai, Number 1 Fitness Club, 5-14-6 Shimo-Takaido, Suginami City, Tokyo 168 Japan; K. Nishimura, General Research and Development Section, Product Development Department, Moon-Star Chemical Corporation, Kurume City, Fukuoka Prefecture, 830-91 Japan; F. Ogita, Swimming Performance Laboratory, National Institute of Fitness and Sport, Shiromizu-cho 1, Kanoya City, Kagoshima Prefecture, 891-23 Japan; M. Miyachi, Department of Health and Sports Sciences, Kawasaki University of Medical Welfare, 288 Matsushima, Kurashiki City, Okayama Prefecture, 701-01 Japan; and K. Yamamoto, Nagoya YMCA, 2-5-29 Kamimaezu, Naka-ku, Nagoya City, Aichi Prefecture, 460 Japan.
Address for correspondence: I. Tabata, Ph.D., Laboratory of Exercise Physiology, Division of Health Promotion, National Institute of Health and Nutrition, 1-23-1 Toyama, Shijuku City, Tokyo 162, Japan.