Tsuda Kouji, Takahira Naonobu, Sakamoto Miki, Shinkai Ato, Kaji Kazuki, Kitagawa Jun
Graduate School of Medical Sciences, Kitasato University, Sagamihara, Kanagawa, Japan.
School of Allied Health Sciences, Kitasato University, Sagamihara, Kanagawa, Japan.
Prog Rehabil Med. 2017 Jul 5;2:20170009. doi: 10.2490/prm.20170009. eCollection 2017.
Venous thromboembolism can be prevented by physical prophylaxis, such as active ankle exercise (AAE), in addition to pharmacological treatment. However, the relationship between the intensity of triceps surae (TS) exercise and venous flow is unclear, and physical thromboprophylaxis has not been established for patients with leg cast immobilization. The goals of the current study were to clarify the degree of intensity of TS isotonic contraction required to increase peak blood velocity (PV) in the superficial femoral vein to higher than that at no resistance and to determine if TS isometric contraction can increase PV.
A prospective, nonrandomized, controlled trial was performed in 20 healthy young adult men. PVs at rest and during one TS isotonic or isometric contraction were measured using Doppler ultrasonography. Isotonic contraction intensity was defined as no resistance with contraction of maximum effort and 25%, 50%, 75%, and 100% of one repetition maximum (1RM). Isometric contraction intensity was defined as 15-35%, 40-60%, 65-85%, and 90-100% of the maximal voluntary contraction.
Isotonic contraction at 75% 1RM (51.4 cm/s [95% CI, 40.1-62.6]) and 100% 1RM (54.9 cm/s [95% CI, 43.1-66.7]) significantly increased PV compared to that with no resistance (41.0 cm/s [95% CI, 32.2-49.8]) (P=0.005, 0.001, respectively). Isometric contraction increased PV significantly at all intensities (all P≤0.002).
Applying resistance at ≥75% 1RM increases venous flow and enhances the effect of AAE with TS isotonic contraction. TS isometric contraction may serve as thromboprophylaxis for patients undergoing leg cast immobilization.
除药物治疗外，可通过物理预防措施（如主动踝关节运动[AAE]）预防静脉血栓栓塞。然而，腓肠肌（TS）运动强度与静脉血流之间的关系尚不清楚，且尚未为腿部石膏固定患者确立物理性血栓预防措施。本研究的目的是明确将股浅静脉峰值血流速度（PV）提高至高于无阻力时所需的TS等张收缩强度，并确定TS等长收缩是否能增加PV。
对20名健康年轻成年男性进行了一项前瞻性、非随机对照试验。使用多普勒超声测量静息状态以及一次TS等张或等长收缩期间的PV。等张收缩强度定义为最大努力收缩时无阻力以及1次重复最大值（1RM）的25%、50%、75%和100%。等长收缩强度定义为最大自主收缩的15 - 35%、40 - 60%、65 - 85%和90 - 100%。
与无阻力时（41.0 cm/s [95% CI，32.2 - 49.8]）相比，75% 1RM（51.4 cm/s [95% CI，40.1 - 62.6]）和100% 1RM（54.9 cm/s [95% CI，43.1 - 66.7]）的等张收缩显著增加了PV（分别为P = 0.005，0.001）。等长收缩在所有强度下均显著增加了PV（所有P≤0.002）。
施加≥75% 1RM的阻力可增加静脉血流，并增强TS等张收缩时AAE的效果。TS等长收缩可为腿部石膏固定患者提供血栓预防作用。
