Department of Physical Therapy, Tzu-Chi College of Technology, Department of Physical Therapy, Tzu-Chi University, Hualien, Taiwan.
Phys Ther. 2012 Mar;92(3):448-53. doi: 10.2522/ptj.20100394. Epub 2011 Dec 1.
Contrast baths have been adopted widely in clinics. However, the time ratio of heat to cold modalities has not been well established.
The purpose of this study was to explore the effect of time ratio on brachial artery mean blood velocity (aMBV) and determine the optimal duration in the second heating phase.
This was a within-participant, repeated-measures, experimental study.
Thirty-four young volunteers who were healthy were recruited. Each participant performed 2 kinds of contrast baths within 2 separate sessions. In the first trial with a fixed time ratio, participants immersed their left hands in a 40°C hot bath for 3 minutes and then in an 18°C cold bath for 1 minute. This procedure was repeated 3 times. In the second trial, after the initial 3-minute hot bath and 1-minute cold bath, a 10-minute 40°C hot bath immersion was adopted as the second cycle. A color Doppler ultrasound scanner was used to measure aMBV, which was used to calculate the percentage of change related to the baseline (aMBV%) and the fluctuation in the heating phases (ΔaMBV%).
In the first trial, compared with the first heating phase, the ΔaMBV% was significantly lower by 57% and by 46% in the second and third heating phases, respectively. In the second trial, the ΔaMBV% beyond the 7th minute did not reach a significantly lower level.
The results cannot be generalized to elderly individuals or patients with medical conditions.
A longer duration in the second heating phase during contrast baths was required to produce a sufficient fluctuation in blood flow.
对比浴在临床上已广泛应用，但热冷模式的时间比例尚未得到很好的确定。
本研究旨在探讨时间比例对肱动脉平均血流速度（aMBV）的影响，并确定第二次加热期的最佳持续时间。
这是一项在参与者内、重复测量、实验研究。
招募了 34 名健康的年轻志愿者。每位参与者在 2 个单独的时间段内进行了 2 种对比浴。在第一次试验中，采用固定的时间比例，参与者将左手浸入 40°C 的热水浴中 3 分钟，然后浸入 18°C 的冷水浴中 1 分钟。此过程重复 3 次。在第二次试验中，在最初的 3 分钟热水浴和 1 分钟冷水浴后，采用 10 分钟 40°C 的热水浴浸泡作为第二个周期。使用彩色多普勒超声扫描仪测量 aMBV，用于计算与基线相关的变化百分比（aMBV%）和加热阶段的波动（ΔaMBV%）。
在第一次试验中，与第一加热期相比，第二和第三加热期的ΔaMBV%分别显著降低了 57%和 46%。在第二次试验中，第 7 分钟以后的ΔaMBV%没有达到明显更低的水平。
结果不能推广到老年人或有医疗条件的患者。
对比浴中第二加热期需要更长的持续时间才能产生足够的血流波动。
