Takuya Osada's research while affiliated with Tokyo Medical University and other places

Publications (4)

Article
Full-text available
An elevated intramuscular pressure during a single forearm isometric muscle contraction may restrict muscle hyperemia. However, during repeated isometric exercise, it is unclear to what extent mechanical compression and muscle vasodilatation contribute to the magnitude and time course of beat-to-beat limb hemodynamics, due to alterations in leg vas...
Article
Full-text available
Given recent technological developments, ultrasound Doppler can provide valuable measurements of blood velocity/flow in the conduit artery with high temporal resolution. In human-applied science such as exercise physiology, hemodynamic measurements in the conduit artery is commonly performed by blood flow feeding the exercising muscle, as the incre...

Citations

... Previous evidence revealed that, although both types of leg exercises were able to increase femoral artery blood flow and velocity, isometric exercise produced greater blood flow fluctuations than isotonic exercise. 28 Another potential mechanism involves differences in muscle deoxygenation. Lowintensity isotonic forearm exercise demonstrated reduced forearm venous oxygen saturations during the ambient condition, which further reduced during the ischemic condition. ...
... Therefore, the purpose of the current study was to compare acute changes in patellar tendon microvascular blood flow, utilizing NIRS to monitor changes in total and oxygenated hemoglobin content (THb, as a surrogate for microvascular blood flow and HbO 2 , as a surrogate for oxygen delivery to the tendon) after performing sets of repeated isometric contractions at different intensities. Based on the positive effects that external loading has on the post-exercise hyperemic response in muscle, 27 we hypothesized that patellar tendon THb and HbO 2 response will increase with increasing loading intensity. We expect that the findings from our study will further the understanding on the effects tendon loading has on the post-exercise hyperemic response, one of the proposed therapeutic mechanisms that stimulates tendon healing and adaptation. ...
... Moreover, rapid changes in blood velocity in a conduit artery located in a gap into a major muscle group can also be detected with muscle contraction and relaxation and/or cardiac beat-by-beat during exercise, muscle contraction frequency and workload, and in relation to vasodilatation/vasoconstriction [9] [10] [11] [12]. In previous studies in healthy legs on exercise leg blood flow (LBF), there were positive linear correlations between T. Osada unilateral LBF and workload during steady state dynamic leg exercise with a validated operator technique [13] [14] [15] [16]. ...
... Postischemic hyperemia may be achieved with voluntary masseter and temporal muscle contraction (Supporting Information Figure S2). 25 In the case of MXA and MMA, the muscles' constriction unavoidably narrows the acoustic window, causing the MMA, and sometimes even the MXA to become unavailable. Temporal region compression does not alter the flow in MXA or MMA, probably because they supply mainly the facial area. ...