@article{oai:tokaigakuin-u.repo.nii.ac.jp:00002152,
 author = {蘭, 和真 and 澤田, 文吉 and 市島, 憲郎 and Araragi, Kazuma and Sawada, Bunkichi and Ichishima, Norio},
 journal = {東海女子大学紀要, Bulletin of Tokai Women's University},
 month = {Jan},
 note = {本研究の目的は等尺性収縮を行なった際の筋皮労過程及び筋疲労回復過程の筋の状態を表面務電図の平均パワー周波数及ぴ筋電図積分値から検討することであった。そのため, 健康な成人男子5名を被検者とし上腕二頭筋の収縮を25%MVC及ぴ50%MVC負荷でそれぞれ疲労因臓まで行なわせた後間欠的に短時間の収縮を行なわせた。疲労過程及び疲労回復過程の表面筋電図を上腕二頭筋より導出し検討を加えた。その結果次のことが明らかとなった。1)疲労前の状態では平均パワー周波数は25%MVC負荷時より50%MVC負荷時の方が高い値を示した。2)50%MVC負荷時の平均パワー周波数は疲労とともに指数関数的に低下し3～5分の休息で完全に疲労前の状態に戻った。3)25%MVC負荷時の平均パワー周波数は疲労過程及び疲労回復過程を通してほとんど変化がみられなかった。4)50%MVC負荷時の積分値は疲労に伴い直線的に増大した。15分間の休息ではその低下はみられなかった。5)25%MVC負荷時の積分値は疲労に伴い2次関数的に増大した。しかし, 疲労困憊後1分間の休息で急速に低下し以後は徐徐に低下した。以上のことから, 疲労過程及ぴ疲労回復過程のいずれにおいても負荷重量によって周波数成分及び積分値が影響を受けることが明らかとなった。閾値張力がFT線維とST線維異なるため負荷重量によって運動単位の動員様式に変化が生じることが一因であると考えられた。一方, 疲労によって低下した平均パワー周波数が短時間で疲労前の状態に戻ったという事実は, 疲労に伴うパワースペクトラムの低周波数化が乳酸による影響だけではないことを示唆するものであった。, The purpose of the present study was to investigate the muscular activities during fatigue and recovery by means of electromyogram (EMG). The EMG power spectrum and the integrated EMG (IEMG) of the surface EMG recorded over the muscle of biceps brachii was examined in five male subjects during fatiguing isometric contraction and following intermittent brief isometric contractions. The mean power frequency (MPF) was calculated and used as a single estimate of the EMG power spectrum. Contraction was maintained at a constant force of 25 and 50% of their maximum voluntary contraction (MVG). Following results were obtained from present stuby. 1) In unfatigued condition at 50% of MVC load the MPF showed higher values than at 25% of MVC load. 2) During fatiguing contraction at 50% of MVC load the MPF showed exponential decrement with time, during recovery returning in basal level within 5 mm. 3) The MPF varied little during fatiguing contraction and recovery at 25% of MVC load. 4) During fatiguing contraction at 50% of MVC load the IEMG showed linear increment with time, and during recovery it showed little decrement within 15mm. 5) During fatiguing contraction at 25% of MVC load the IEMG showed quadratic fanctional increment with time, and during recovery it showed rapid decrement within 1mm. It is clarified that the power spectrum and the IEMG during fatiguing contraction and re-covery are effected by muscular force level. Recuruitment order of motor unit is altered by muscular force level so that the threshold force of motor unit is different between FT and ST fiber. It is suggested that in contraction at 25% of MVC load ST fiber that has low con-duction velocity of muscle fiver action potential, little lactate production and rapid lactate removal is recruited prior. In contraction at 50% of MVC load FT fiber that has high con-duction velocity of muscle fiber action potential, much lactate production and show lactate removal is recruited prior. So these tow factors may effect on the power spectrum and IEMG., 7, KJ00002499685},
 pages = {49--59},
 title = {表面筋電図のパワースペクトラムからみた筋疲労回復過程},
 volume = {6},
 year = {1986},
 yomi = {アララギ, カズマ and サワダ, ブンキチ and イチシマ, ノリオ}
}