Temporal Change of Tissue Blood Oxygen Saturation in Rat Skeletal Muscle after Blood Flow Restriction by Manchette

Abstract

[Purpose] This study was made to clarify the conditions of temporary blood flow restriction (BFR) that can produce muscle hypertrophy. [Participants and Methods] Five male Wistar rats were subjected to BFR of 200 mmHg in the lower leg muscle using a manchette. Tissue oxygen saturation (StO₂) at the start of BFR was set to 100%, and the lowest StO₂ value within 6 minutes from the start of BFR was set to 0% (%StO₂). StO₂ for each minute was compared from the start until 6 minutes. [Results] % StO₂ showed a downward trend for 3 minutes after the start of BFR, and then decreased only slightly before reaching a plateau. [Conclusion] When %StO₂ is relatively low, there is a greater effect of muscle hypertrophy, and the BFR time is 4 minutes or more. However, the duration of the low %StO₂ state is also considered to be a factor inducing muscle hypertrophy, so further investigation is necessary.