At The Spa Shop, we’ve always known that relaxing in a spa pool feels amazing — but new research suggests it may also deliver some of the strongest passive health benefits compared to traditional and infrared saunas.

A recent RNZ Sunday Morning podcast discussed a first-of-its-kind study comparing:

• Spa pools (hot water immersion)
• Traditional saunas
• Far-infrared saunas

The results were surprisingly clear.

Spa Pools Delivered the Strongest Physiological Response

The study found spa pool immersion raised core body temperature more effectively than either type of sauna.

Water transfers heat far more efficiently than air, meaning even at around 40°C, spa pools produced greater internal heating than traditional saunas at around 80°C.

This led to:

• Greater increases in core body temperature
• Higher cardiovascular activity
• Stronger overall body response

Researchers also recorded an increase in cardiac output of around 3.7 litres per minute — similar to moderate aerobic exercise.

Heart, Circulation & Immune Benefits

Hot water immersion produced the strongest overall cardiovascular effect of all therapies tested, suggesting spa pools may help:

• Support healthy blood flow
• Assist cardiovascular function
• Encourage recovery and relaxation
• Deliver a gentle “exercise-like” response

Even more interesting, spa pools were the only therapy to trigger a measurable immune response, including increases in IL-6, NK cells, and CD8+ T cell activity after 24–48 hours.

Traditional saunas showed some benefits, but not the same immune activation, while infrared saunas showed the least overall physiological impact.

Traditional Saunas Still Have Value

Traditional saunas still increased core temperature and circulation, and remain popular for relaxation, stress relief, and muscle recovery. However, they were less effective overall in measurable physiological response compared to spa pools.

Why Spa Pools Are Becoming a Wellness Essential in NZ

Modern spa pools are increasingly part of everyday wellbeing routines. A quality spa pool can help you:

• Relax after work
• Ease muscle tension
• Support recovery
• Improve family wellbeing time
• Maintain year-round wellness

Premium Spa Pools & Refurbished Options at The Spa Shop

Premium hydrotherapy systems — such as those from Hot Spring — are designed to maximise therapeutic benefit through:

Targeted Hydrotherapy Jets
Designed to improve circulation and muscle recovery.

Energy-Efficient Design
Helps maintain stable temperature with lower running costs.

Advanced Filtration Systems
Supports cleaner water with less maintenance.

Ergonomic Seating
Improves comfort and enhances the effectiveness of hydrotherapy sessions.

The Spa Shop also offers carefully selected refurbished Hot Spring spa pools, professionally checked and prepared for reliable performance. This gives customers access to premium hydrotherapy features at a more affordable price.

Final Thoughts

The latest research reinforces what many spa owners already experience: spa pools offer powerful benefits for circulation, recovery, and relaxation — often outperforming traditional heat therapies in measurable effects.

At The Spa Shop, we offer a full range of spa pools, chemicals, filters, and accessories to help you get the most from your wellness routine.