In a nutshell

• Hot water immersion significantly outperformed both traditional and infrared saunas, leading to greater increases in core body temperature, heart rate, cardiac output, and reductions in blood pressure—mimicking the benefits of moderate-intensity exercise.

• Only hot water immersion triggered measurable immune responses, including spikes in interleukin-6 and increases in natural killer cells and cytotoxic T-cells up to 48 hours later, suggesting potential long-term immune benefits.

• The study highlights how hot baths offer a practical, affordable way to gain cardiovascular and immune system benefits, challenging the trend of expensive sauna therapies and underscoring the importance of consistent, sustained heat exposure for maximum effects.

EUGENE, Ore. — If you're looking to boost your cardiovascular health without breaking a sweat at the gym, you might want to skip the trendy sauna sessions and head straight for a hot bath instead. A new study comparing three popular heat therapy methods found that soaking in hot water delivers more powerful health benefits than either traditional or infrared saunas.