至的運動強度の指標になる二重積屈曲点法に収縮期の血圧変化が及ぼす影響

　至適運動強度の指標になる無酸素性作業閾値(anaerobicthreshold:AT)および乳酸性作業閾
値(lactatethreshoId:LT)を簡便に測定する方法として二重積屈曲点(doubleproductbreakpoint:
DPBP)法がある。この二重積屈曲点の測定に収縮期の血圧(systolicbloodpressure:SBP)変化が及ぼす影響を明らかにするために,14名の学生(男性10名,女性4名)を被験者とし,ランプ負荷によるべダリング運動を実施した。男性のSBPは低圧と高圧に2つの変異点がみられる3次回帰式となったが,女性には明らかな変異点はみられなかった。二重積(doubleproduct:DP)は男女とも3次回帰式となり,運動終了前に上昇抑制傾向がみられた。これらの結果から,運動強度の変化に伴うSBPの変化は,DPBPパターンに影響することは少ないことが示された。
The anaerobic threshold value or lactate threshold value, which provides a good index of optimum exercise strength, can be estimated from the eurve of double-product break-points (DPBPs) measured during bicycle ramp loading exercise. In order to elucidate the effect of systolic blood pressure (SBP) on the DPBP response, bicycle ramp loading exercises were eonducted by 1 4 student volunteers (10 males and 4 females). Third regression curves with two conversion points corresponding to low and high SBP were detected in the male subjects. By contrast, the SBP regression curves of female subjects exhibited no such clear conversion points. Third regression curves were also obtained from the double-product values measured during ramp loading exercises in both sexes, and the ascending curves tended to be depressed near the end of the exercise. The patterns of the DPBP response, however, essentially were unaffeeted by the various SBP values resulting frorn the change in exercise intensity.