caa a22 4500 469055200 CHVBK 20180323132841.0 cr unu---uuuuu 170328e19921101xx s 000 0 eng 10.1007/BF00843763 doi (NATIONALLICENCE)springer-10.1007/BF00843763 Phosphorus-31 magnetic resonance spectroscopy of forearm flexor muscles in student rowers using an exercise protocol adjusted for differences in cross-sectional muscle area [Elektronische Daten] [Masayuki Nishida, Hirotaka Nishijima, Kazuya Yonezawa, Isao Sato, Teisuke Anzai, Kohichi Okita, Hisakazu Yasuda] Summary: To assess exercise energy metabolism of forearm flexor muscles in rowers, six male student rowers and six control subjects matched for age and sex were studied using phosphorus-31 magnetic resonance spectroscopy (31P-MRS). Firstly, to adjust for the effect of differences in cross-sectional muscle area, the maximal cross-sectional area (CSAmax) of the forearm flexor muscles was estimated in each individual using magnetic resonance imaging. Multistage exercise was then carried out with an initial energy production of 1 J · cm−2 CSAmax for 1 min and an increment of 1 J · cm−2 CSAmax every minute to the point of muscle exhaustion. A series of measurements of31P-MRS were performed every minute. The CSAmax was significantly greater in the student rowers than in the control subjects [19.8 (SD 2.2) vs 17.1 (SD 1.2) cm2,P<0.05]. The absolute maximal exercise intensity (J · min−1) was greater in the rowers than in the control subjects. However, the maximal exercise intensity per unit of muscle cross sectional area (J · min−1 · cm−2) was not significantly different between the two groups. During mild to moderate exercise intensities, a decrease in phosphocreatine and an increase in inorganic phosphate before the onset of acidosis were significantly less in the rowers, indicating a requirement of less adenosine 5′-diphosphate to drive adenosine 5′-triphosphate production. The onset of acidosis was also significantly delayed in the rowers. No difference was observed in forearm blood flow between the two groups at the same exercise intensity (J · min−1 · cm−2). These results demonstrated that the findings of the maintenance of a higher level of phosphocreatine and a lower level of inorganic phosphate with less acidosis observed in the rowers were the results of the intrinsic characteristics of energy metabolism of their muscles and that these characteristics were independent of their greater cross-sectional muscle area. Springer-Verlag, 1992 Exercise energy metabolism nationallicence Cross-sectional muscle area Phosphorus-31 magnetic resonance spectroscopy nationallicence Forearm flexor muscles nationallicence Nishida Masayuki Department of Cardiovascular Medicine, Hokkaido University School of Medicine, Kita-15, Nishi-7, Kitaku, 060, Sapporo, Japan aut Nishijima Hirotaka Department of Cardiovascular Medicine, Hokkaido University School of Medicine, Kita-15, Nishi-7, Kitaku, 060, Sapporo, Japan aut Yonezawa Kazuya Department of Cardiovascular Medicine, Hokkaido University School of Medicine, Kita-15, Nishi-7, Kitaku, 060, Sapporo, Japan aut Sato Isao Department of Cardiovascular Medicine, Hokkaido University School of Medicine, Kita-15, Nishi-7, Kitaku, 060, Sapporo, Japan aut Anzai Teisuke Department of Cardiovascular Medicine, Hokkaido University School of Medicine, Kita-15, Nishi-7, Kitaku, 060, Sapporo, Japan aut Okita Kohichi Department of Cardiovascular Medicine, Hokkaido University School of Medicine, Kita-15, Nishi-7, Kitaku, 060, Sapporo, Japan aut Yasuda Hisakazu Department of Cardiovascular Medicine, Hokkaido University School of Medicine, Kita-15, Nishi-7, Kitaku, 060, Sapporo, Japan aut European Journal of Applied Physiology and Occupational Physiology Springer-Verlag 64/6(1992-11-01), 528-533 0301-5548 64:6<528 1992 64 421 https://doi.org/10.1007/BF00843763 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00843763 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Nishida Masayuki Department of Cardiovascular Medicine, Hokkaido University School of Medicine, Kita-15, Nishi-7, Kitaku, 060, Sapporo, Japan aut NATIONALLICENCE 700 1- Nishijima Hirotaka Department of Cardiovascular Medicine, Hokkaido University School of Medicine, Kita-15, Nishi-7, Kitaku, 060, Sapporo, Japan aut NATIONALLICENCE 700 1- Yonezawa Kazuya Department of Cardiovascular Medicine, Hokkaido University School of Medicine, Kita-15, Nishi-7, Kitaku, 060, Sapporo, Japan aut NATIONALLICENCE 700 1- Sato Isao Department of Cardiovascular Medicine, Hokkaido University School of Medicine, Kita-15, Nishi-7, Kitaku, 060, Sapporo, Japan aut NATIONALLICENCE 700 1- Anzai Teisuke Department of Cardiovascular Medicine, Hokkaido University School of Medicine, Kita-15, Nishi-7, Kitaku, 060, Sapporo, Japan aut NATIONALLICENCE 700 1- Okita Kohichi Department of Cardiovascular Medicine, Hokkaido University School of Medicine, Kita-15, Nishi-7, Kitaku, 060, Sapporo, Japan aut NATIONALLICENCE 700 1- Yasuda Hisakazu Department of Cardiovascular Medicine, Hokkaido University School of Medicine, Kita-15, Nishi-7, Kitaku, 060, Sapporo, Japan aut NATIONALLICENCE 773 0- European Journal of Applied Physiology and Occupational Physiology Springer-Verlag 64/6(1992-11-01), 528-533 0301-5548 64:6<528 1992 64 421 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer