Passive heat therapy improves endothelial function, arterial stiffness and blood pressure in sedentary humans

Objective: To test whether passive heat therapy improves vascular function and blood pressure in sedentary adults. Participants underwent repeated heat exposures over several weeks, and endothelial function, arterial stiffness, and blood pressure were measured before and after the intervention. The treatment group showed improved flow-mediated dilation, reduced arterial stiffness, and modest lowering of blood pressure relative to baseline and, in some comparisons, relative to control. The physiologic pattern suggested enhanced vascular responsiveness and better circulatory adaptation to repeated thermal stress. The intervention was generally well tolerated, with no major adverse safety signals reported in the study population. These results support the concept that heat exposure can act as a cardiovascular stimulus with measurable vascular benefits, especially in inactive individuals who may have limited baseline conditioning. However, the trial was small and short, and the durability of the effects remains uncertain. Larger studies are needed to understand dose, frequency, and long-term safety.