Permalink : http://hdl.handle.net/2115/76404

JaLCDOI : 10.14943/b.edu.135.43

KEYWORDS : Tissue oxygen index;Amplitude of oscillation;Exercise intensity;Power spectral density;組織酸素指数;振動の振幅;運動強度;パワースペクトル密度

　Aim. We hypothesized that an increase in the interaction of the biochemical substance due to the high exercise intensity could increase the amplitude of oscillation in TOI. In order to test this hypothesis, we examined whether oscillation of the tissue oxygen index (TOI) during exercise was influenced by the difference between low and high intensity exercises. 　Methods. Nine subjects performed low-intensity exercise (Low-E) and high-intensity exercise (High-E) for 12 min. TOI was measured from the vastus lateralis muscle by near-infrared spectroscopy. TOI from 3 min to 12 min during exercise was analyzed by fast Fourier analysis to obtain power spectral density (PSD). PSD was integrated in the low frequency range (<0.025 Hz). 　Results. The maximal peak of PSD appeared at 0.0039 ± 0 Hz in Low-E and at 0.0048 ± 0.002 Hz in High-E. There was no significant difference in the maximal peak of PSD between the two exercises. PSD at 0.016 Hz during High-E (43 ± 33 %2/Hz) was significantly higher than that during Low-E (13 ±6 %2/Hz). The integrated PSD was significantly larger in High-E (2.0 ±1.6 %2) than in Low-E (0.9 ± 0.6 %2). 　Conclusion. The results suggest that interactions among biochemical substances involved in oxidative metabolism occur more strongly in High-E than in Low-E.
　高い運動強度による生化学物質の相互作用の増加は、TOIにおける振動の振幅を増加させる可能性があると仮説した。この仮説を検証するために、我々は、運動中の組織酸素指数（TOI）の振動が、低強度運動と高強度運動の違いによって影響を受けるかどうかを調べた。低強度運動（Low-E）および高強度運動（High-E）を12分間行った。TOIは、近赤外分光法により外側広筋から測定した。運動中の3分から12分までのTOIを、パワースペクトル密度（PSD）を得るための高速フーリエ解析によって分析した。低周波帯で積分されたPSDは、High-E（2.0±1.6％2）ではLow-E（0.9±0.6％2）よりも有意に大きかった。これらの結果は、酸化的代謝に関与する生化学物質間の相互作用が、Low-EよりもHigh-Eにおいてより強く生じることを示唆している。