文献一覧: Japan Society of Exercise and Sports Physiology (出版者)

2 0 0 0 IR Low-frequency isometric training, 1-day of training every 2 weeks, increases muscle strength in untrained subjects

著者: Ohmori Hajime Kume Toshiro Sasaki Kazushige OHYAMA BYUN Keigo TAKAHASHI Hideyuki KUBOTA Tatsumasa
出版者: Japan Society of Exercise and Sports Physiology
雑誌: Advances in exercise and sports physiology (ISSN:13403141)
巻号頁・発行日: vol.16, no.1, pp.1-5, 2010-10
被引用文献数: 1

The purpose of this study was to investigate the effects of low-frequency isometric training (1 day of training every 2 weeks) on muscle strength, which had been thought to have no effect. Fourteen male university students who had not experienced hard strength training were randomly assigned to train either 1 day per 2 weeks (2T group, n=7) or 1 day per 3 weeks (3T group, n=7). The 2T and 3T groups trained the knee extensors of the right leg by producing 3 sets of 5 seconds maximal isometric contraction per day for 8 weeks and 12 weeks, respectively. After 8 weeks of training, in the 2T group, maximal isometric torque in the trained leg significantly increased 15.0% (208.3±18.4Nm to 237.4±19.5Nm); iEMG of the m. rectus femoris significantly increased 30.7%; and the iEMG of the m. vastus lateralis increased 43.6% without any significant difference. On the other hand, there was no change in the cross-sectional area of the m. quadriceps femoris. The same measures in the untrained leg of the 2T group and in both legs of the 3T group were not changed after training. These results suggest that 1) low-frequency isometric training 1 day per 2 weeks increases muscle strength in untrained subjects and 2) the improvement in strength is mainly accounted for by neural factors.

2018-07-24 05:59:30
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https://ci.nii.ac.jp/naid/110007880129

1 0 0 0 IR Relationship between dehydration, rehydration and decreases in exercise performance during various sports in hot environments

著者: Yoshida Tetsuya Takanishi Toshimasa Nakai Seiichi YORIMOTO Akira MORIMOTO Taketoshi
出版者: Japan Society of Exercise and Sports Physiology
雑誌: Advances in exercise and sports physiology (ISSN:13403141)
巻号頁・発行日: vol.8, no.3, pp.71-76, 2002-10

YOSHIDA, T., TAKANISHI, T., NAKAI, S., YORIMOTO, A. and MORIMOTO, T., Relationship between Dehydration, Rehydration and Decreases in Esercise Performance During Various Sports in Hot Environments. Abv. Exerc. Sports Physiol., Vol.8, No.3 pp.71-76, 2002. The purpose of this study was to analyze the effects of dehydration and rehydration on exercise performance during sports activities in summer. We repeated measurements of the step test score (STS), vertical jump (VJ), side step (SS),back strength (BS), and whoke body reaction time (RT) before and after sports activities of Judo (n=9), Tennis (n=6), American footboll (n=8), and Baseball (n=7). the subjects were allowed free access to a sports beverage during each sport activity. Body mass loss(△mb, % of initial body mass), total sweat loss (msw,tot), and rehydration level (REH, % of fluid intake to msw,tot) were slso determined, and correlations between each parameter and changes of exercise performance were assessed. The STS significantly (p<0.05) decreased while VJ, BS, SS, and RT showed no significant decrease with sports activity. In all of the subjects (n=30), the change in STS(%STS) correlated significantly with △mb(r=-0.649, p<0.001) and the RED (r=0.589, p<0.001), but not with msw,tot. However, VJ, BS, SS, and RT were not correlated with △mb, REH or msw,tot. These results suggest that a decrease of aerobic performance is found during various sports activities in hot environments, and it is related to the degree of dehydration and rehydration during sports activity.