The history and future of KAATSU Training
Y. Sato1)
1) Department of Ischemic Circulatory Physiology, The University of Tokyo
Abstract
KAATSU training involves the restriction of blood flow to exercising muscle and is the culmination of nearly 40 years of experimentation with the singular purpose of increasing muscle mass. KAATSU Training consists of performing low-intensity resistance training while a relatively light and flexible cuff is placed on the proximal part of one's lower or upper limbs, which provides appropriate superficial pressure. KAATSU Training should not be confused with training under ischemic conditions which has previously been reported (Sundberg, 1994). KAATSU Training does not induce ischemia within skeletal muscle, but rather promotes a state of blood pooling in the capillaries within the limb musculature. Applied basic and clinical research conducted over the past 10 years has demonstrated that KAATSU Training not only improves muscle mass and strength in healthy volunteers, but also benefits patients with cardiovascular and orthopedic conditions.
Skeletal muscle size and circulating IGF-1 are increased after two weeks of twice daily “KAATSU” resistance training
T. Abe1), T. Yasuda1), T. Midorikawa1), Y. Sato2), C. F. Kearns3), K. Inoue4), K. Koizumi5) and N. Ishii6)
1) Department of Exercise and Sport Science, Tokyo Metropolitan University
2) Department of Ischemic Circulatory Physiology, The University of Tokyo
3) Cardiovascular/Endocrine Biology, Schering-Plough Research Institute
4) Orthopedic Medical Clinic
5) Department of Radiology, Tokyo Medical Uiversity Hachioji Medical Center
6) Department of Life Science, University of Tokyo
Abstract
This study investigated the effects of twice daily sessions of low-intensity resistance training (LIT, 20% of 1-RM) with restriction of muscular venous blood flow (namely “LIT-Kaatsu” training) for two weeks on skeletal muscle size and circulating insulin-like growth factor-1 (IGF-1). Nine young men performed LIT-Kaatsu and seven men performed LIT alone. Training was conducted two times / day, six days / week for 2 weeks using 3 sets of two dynamic exercises (squat and leg curl). Muscle cross-sectional area (CSA) and volume were measured by magnetic resonance imaging at baseline and 3 days after the last training session (post-testing). Mid-thigh muscle-bone CSA was calculated from thigh girth and adipose tissue thickness, which were measured every morning prior to the training session. Serum IGF-1 concentration was measured at baseline, mid-point of the training and post-testing. Increases in squat (17%) and leg curl (23%) one-RM strength in the LIT-Kaatsu were higher (p<0.05) than those of the LIT (9% and 2%). There was a gradual increase in circulating IGF-1 and muscle-bone CSA (both p<0.01) in the LIT-Kaatsu, but not in the LIT. Increases in quadriceps, biceps femoris and gluteus maximus muscle volume were, respectively, 7.7%, 10.1% and 9.1% for LIT-Kaatsu (p<0.01) and 1.4%, 1.9% and -0.6% for LIT (p>0.05). There was no difference (p>0.05) in relative strength (1-RM / muscle CSA) between baseline and post-testing in both groups. We concluded that skeletal muscle hypertrophy and strength gain occurred after two weeks of twice daily LIT-Kaatsu training.
Effects of low-intensity “KAATSU” resistance exercise on hemodynamic and growth hormone responses
H. Takano1), T. Morita1), H. Iida1), M. Kato1), K. Uno1), K. Hirose2)4), A. Matsumoto1), K. Takenaka1), Y. Hirata1), T. Furuichi4), F. Eto2), R. Nagai1), Y. Sato3) and T. Nakajima1)3)
1) Department of Cardiovascular Medicine, University of Tokyo
2) Department of Rehabilitation, Faculty of Medicine, University of Tokyo
3) Department of Ischemic Circulatory Physiology, Kaatsu Training, University of Tokyo
4) Department of Rehabilitation, Dokkyo University School of Medicine
Abstract
Growth hormone (GH) is secreted in a pulsatile fashion during exercise, which promotes skeletal muscle growth and muscle strength. We compared the effects of different types of short-term low-intensity resistance exercise (STLIRE) on the hemodynamic and GH responses of men aged 20 to 45 years. Eleven untrained men performed 30 repetitions for 2 to 4 sets (mean 61 ± 7 repetitions) until fatigue for bilateral leg extension-flexion exercise (20% of 1 RM -Proteus Multi Exercise Machine) under the conditions of reduced muscle blood flow by applied pressure at the proximal ends of both legs by a specially-designed belt (Kaatsu Training). In the controlled exercise condition, without Kaatsu (n=9), subjects again performed the same exercise protocol as described above. Finally, a group of 5 men performed 3 sets of 10 repetitions using the Power Rehabilitation machine. Hemodynamic parameters were measured by using the impedance cardiography. Serum concentrations of GH, noradrenaline (NOR), and lactate were also measured. STLIRE with Kaatsu significantly increased GH, compared to STLIRE without Kaatsu. Maximal heart rate (HR) and blood pressure (BP) in STLIRE with Kaatsu were higher when compared to the control condition, however, stroke volume (SV) was lower compared to the controlled condition due to a decreased venous return induced by Kaatsu training. Total peripheral resistance (TPR) did not change significantly. The increase in NOR and lactate in STLIRE with Kaatsu was also significantly higher than without Kaatsu. These results suggest that “Kaatsu” leg resistance exercise caused a significant exercise-induced GH response even in STLIRE, with a reduction of cardiac preload during exercise. The results of the study indicate that Kaatsu training may become a unique method for rehabilitation in patients with cardiac diseases or low physical fitness.
