Yosuke Yamato1,2, Yuya Higaki2, Shumpei Fujie2, Natsuki Hasegawa2, Naoki Horii2,3, Hiroki Aoyama1, Yoshihiro Yamashina1, Shigehiko Ogoh4, Motoyuki Iemitsu5. 1. Department of Physical Therapy, Aino University, Osaka, Japan. 2. Faculty of Sport and Health Science, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga, 525-8577, Japan. 3. Research Fellow of Japan Society for the Promotion of Science, Tokyo, Japan. 4. Department of Biomedical Engineering, Toyo University, Saitama, Japan. 5. Faculty of Sport and Health Science, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga, 525-8577, Japan. iemitsu@fc.ritsumei.ac.jp.
Abstract
PURPOSE: Passive stretching reduces stiffness in the lower limb arteries of the stretched limb. To address this physiological mechanism, we measured the change in shear rate in the posterior tibial artery during a single bout of one-legged passive calf stretching compared with that in the non-stretched leg. METHODS: The diameter, mean blood velocity, blood flow, and shear rate in the posterior tibial artery were measured using Doppler ultrasound before (baseline), during, and after a one-legged passive intermittent calf stretching procedure (six repetitions of 30-s static stretch with 10-s relaxation) in nine healthy young men. RESULTS: In the posterior tibial artery of the stretched leg, the arterial diameter significantly decreased from baseline during the stretching period (baseline vs. stretching period of the 6th set, 0.19 ± 0.01 vs. 0.18 ± 0.01 cm, P < 0.05) without any change in shear rate and mean blood velocity. In contrast, during the relaxation period, the mean blood velocity (baseline vs. relaxation period of the 5th set, 2.98 ± 0.54 vs. 6.25 ± 1.48 cm/s) increased, and consequently, the shear rate (baseline vs. relaxation period of the 5th set, 66.75 ± 15.39 vs. 122.85 ± 29.40 s-1) increased (each P < 0.01); however, there was no change in arterial diameter. In contrast, these values in the non-stretched leg were unchanged at all-time points. CONCLUSIONS: The stretching procedure increased the shear rate in the peripheral artery of the stretched leg during the relaxation period. This finding indicates that the local hemodynamic response (possibly through endothelial function), resulting from an increase in shear stress, may contribute to stretching-induced attenuation of local arterial stiffness.
PURPOSE: Passive stretching reduces stiffness in the lower limb arteries of the stretched limb. To address this physiological mechanism, we measured the change in shear rate in the posterior tibial artery during a single bout of one-legged passive calf stretching compared with that in the non-stretched leg. METHODS: The diameter, mean blood velocity, blood flow, and shear rate in the posterior tibial artery were measured using Doppler ultrasound before (baseline), during, and after a one-legged passive intermittent calf stretching procedure (six repetitions of 30-s static stretch with 10-s relaxation) in nine healthy young men. RESULTS: In the posterior tibial artery of the stretched leg, the arterial diameter significantly decreased from baseline during the stretching period (baseline vs. stretching period of the 6th set, 0.19 ± 0.01 vs. 0.18 ± 0.01 cm, P < 0.05) without any change in shear rate and mean blood velocity. In contrast, during the relaxation period, the mean blood velocity (baseline vs. relaxation period of the 5th set, 2.98 ± 0.54 vs. 6.25 ± 1.48 cm/s) increased, and consequently, the shear rate (baseline vs. relaxation period of the 5th set, 66.75 ± 15.39 vs. 122.85 ± 29.40 s-1) increased (each P < 0.01); however, there was no change in arterial diameter. In contrast, these values in the non-stretched leg were unchanged at all-time points. CONCLUSIONS: The stretching procedure increased the shear rate in the peripheral artery of the stretched leg during the relaxation period. This finding indicates that the local hemodynamic response (possibly through endothelial function), resulting from an increase in shear stress, may contribute to stretching-induced attenuation of local arterial stiffness.
Authors: Daniel J Green; Maria T E Hopman; Jaume Padilla; M Harold Laughlin; Dick H J Thijssen Journal: Physiol Rev Date: 2017-04 Impact factor: 37.312
Authors: Guohao Dai; Olga Tsukurov; Michael Chen; Jonathan P Gertler; Roger D Kamm Journal: Am J Physiol Heart Circ Physiol Date: 2002-06 Impact factor: 4.733
Authors: M Kooijman; D H J Thijssen; P C E de Groot; M W P Bleeker; H J M van Kuppevelt; D J Green; G A Rongen; P Smits; M T E Hopman Journal: J Physiol Date: 2007-12-20 Impact factor: 5.182
Authors: Daniel J Green; Ellen A Dawson; Hans M M Groenewoud; Helen Jones; Dick H J Thijssen Journal: Hypertension Date: 2013-11-25 Impact factor: 10.190