METHODS: Fifteen volunteers > 50 years old underwent 8-10 separate 45-min hot tub session over 14 days in this exploratory and mixed methods trial. The participants had maximal oxygen consumption (VO2 max) and other cardiovascular data measured via exercise treadmill testing prior to and after all hot tub sessions. The participants also wore noninvasive fingertip volume clamp monitors while immerged in hot water that calculated systemic vascular resistance, heart rate, blood pressure, and cardiac output in order to ascertain the feasibility and utility of this data. Other laboratory studies were obtained pre- and post-intervention. The protocol was determined feasible if the heat therapy and cardiovascular testing was completed by at least 90% (14/15 subjects). Feasibility of the noninvasive monitor was determined by the fidelity of the results. Secondary exploratory outcomes were analyzed for differences to identify if they are acceptable to include in an efficacy trial.
RESULTS: All participants completed the study protocol identifying the feasibility of the protocol. The noninvasive hemodynamic monitors successfully recorded cardiac output, systemic vascular resistance, heart rate, and blood pressure with fidelity based on the analysis of recordings. In the secondary analyses, we found no difference in the pre- to post-intervention measurement of VO2 max but did find increased exercise duration following hot tub therapy compared with prior to the therapy (571 s versus 551 s).
CONCLUSIONS: The current pilot study protocol is feasible for the purpose of analyzing the effects of heat therapy and cardiovascular performance in older adults while wearing a noninvasive hemodynamic monitor and undergoing treadmill stress testing. Secondary analyses found increased exercise tolerance but no differences in VO2 max following heat sessions.
方法:在这项探索性和混合方法试验中,15名50岁的志愿者在14天内接受了8-10次单独的45分钟热水浴缸训练。参与者在所有热水浴缸会议之前和之后通过运动跑步机测试测量了最大耗氧量(VO2max)和其他心血管数据。参与者还戴着无创指尖容量钳监测仪,同时浸入热水中,计算全身血管阻力,心率,血压,和心输出量,以确定这些数据的可行性和实用性。在干预前后获得了其他实验室研究。如果热疗法和心血管测试完成至少90%(14/15受试者),则确定方案是可行的。非侵入性监测的可行性由结果的保真度确定。分析次要探索性结果的差异,以确定它们是否可以接受纳入疗效试验。
结果:所有参与者完成研究方案,确定方案的可行性。无创血流动力学监测仪成功记录心输出量,全身血管阻力,心率,和基于记录分析的保真度血压。在二次分析中,我们发现,干预前后VO2max的测量值无差异,但与治疗前相比,热水浴缸治疗后的运动持续时间增加(571s对551s).
结论:当前的初步研究方案是可行的,用于分析佩戴无创血流动力学监测仪和进行跑步机压力测试的老年人中热疗法和心血管表现的影响。二次分析发现,运动耐量增加,但热火后的VO2最大值没有差异。