| Title: | Intramuscular metabolism during low-intensity resistance exercise with blood flow restriction |
| Authors: | Suga, Tadashi Browse this author |
| Okita, Koichi Browse this author |
| Morita, Noriteru Browse this author →KAKEN DB |
| Yokota, Takashi Browse this author →KAKEN DB |
| Hirabayashi, Kagami Browse this author |
| Horiuchi, Masahiro Browse this author |
| Takada, Shingo Browse this author →KAKEN DB |
| Takahashi, Tomohiro Browse this author |
| Omokawa, Masashi Browse this author |
| Kinugawa, Shintaro Browse this author →KAKEN DB |
| Tsutsui, Hiroyuki Browse this author →KAKEN DB |
| Keywords: | training |
| sex |
| strength |
| hypertrophy |
| magnetic resonance spectroscopy |
| Issue Date: | 2009 |
| Publisher: | American Physiological Society |
| Journal Title: | Journal of Applied Physiology |
| Volume: | 106 |
| Issue: | 4 |
| Start Page: | 1119 |
| End Page: | 1124 |
| Publisher DOI: | 10.1152/japplphysiol.90368.2008 |
| Abstract: | Although recent studies have reported that low-intensity resistance training with blood flow restriction could stress the muscle effectively and provide rapid muscle hypertrophy and strength gain equivalent to those of high-intensity resistance training, the exact mechanism and its generality have not yet been clarified. We investigated the intramuscular metabolism during low-intensity resistance exercise with blood flow restriction and compared it with that of high-intensity and low-intensity resistance exercises without blood flow restriction using 31P-magnetic resonance spectroscopy. Twenty-six healthy subjects (22 ± 4 yr) participated and performed unilateral plantar flexion (30 repetitions/min) for 2 min. Protocols were as follows: low-intensity exercise (L) using a load of 20% of one-repetition maximum (1 RM), L with blood flow restriction (LR), and high-intensity exercise using 65% 1 RM (H). Intramuscular phosphocreatine (PCr) and diprotonated phosphate (H2PO4−) levels and intramuscular pH at rest and during exercise were obtained. We found that the PCr depletion, the H2PO4− increase, and the intramuscular pH decrease during LR were significantly greater than those in L (P < 0.001); however, those in LR were significantly lower than those in H (P < 0.001). The recruitment of fast-twitch fiber evaluated by inorganic phosphate splitting occurred in only 31% of the subjects in LR, compared with 70% in H. In conclusion, the metabolic stress in skeletal muscle during low-intensity resistance exercise was significantly increased by applying blood flow restriction, but did not generally reach that during high-intensity resistance exercise. This new method of resistance training needs to be examined for optimization of the protocol to reach equivalence with high-intensity resistance training. |
| Type: | article |
| URI: | http://hdl.handle.net/2115/76760 |
| Appears in Collections: | 医学院・医学研究院 (Graduate School of Medicine / Faculty of Medicine) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
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