Research

Hormonal

Eight weeks of passive heat therapy (hot water immersion) significantly improves endothelial function, reduces arterial stiffness, and lowers blood pressure in sedentary young adults, with effects comparable to or exceeding those of exercise training.

If you cannot perform aerobic exercise, consider passive heat therapy (hot tub immersion) as a cardiovascular intervention. Immerse in hot water (approx 40.5°C) 4-5 times a week for 8 weeks, aiming to raise your core body temperature to at least 38.5°C. This protocol has been shown to improve blood vessel function and lower blood pressure in sedentary individuals, potentially offering similar benefits to exercise training.

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We showed that, relative to a sham group which participated in thermoneutral water immersion, heat therapy increased flow-mediated dilation, reduced arterial stiffness, reduced mean arterial and diastolic blood pressure, and reduced carotid intima media thickness, with changes all on par or greater than what is typically observed in sedentary subjects with exercise training.
Vienna E. Brunt et al. · The Journal of Physiology · 2016

Why this rating

Randomized controlled trial design with a sham control, though small sample size (N=20).

Source

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

Vienna E. Brunt et al. · The Journal of Physiology · 2016

DOI 10.1113/jp272453

rct · n=20Cited 295×
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DOI resolved against Crossref · corpus check 2026-06-10

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