Overview
- The high thermal conductivity and immersion environment of hot tubs limit evaporative cooling to sustain a stronger hyperthermic stimulus than in dry or infrared saunas.
- Participants exhibited increased cardiac output and vascular shear stress during hot tub sessions, key factors linked to reduced arterial stiffness and lower resting blood pressure.
- Blood analyses revealed that only hot water immersion elevated inflammatory cytokines and altered immune cell populations, suggesting enhanced immune system activation.
- The trial enrolled twenty physically active adults aged 20 to 28 under controlled conditions to directly compare three passive heat therapies.
- Investigators propose heat therapy as a viable supplement or alternative to exercise for those unable or unwilling to work out, while advising medical clearance to ensure safety.