Exploring physiological and metabolomic changes with sauna and exercise in healthy young volunteers

All participants will receive three interventions (after a control intervention) on separate occasions in a randomised crossover sequence with a minimum of 48 hours washout. Intervention I- Exercise 45 minutes total [2 x 15-minute sessions separated by 10-15-min cool-down (at controlled room temperature, ~25oC)] of monitored exercise on cycle ergometer equivalent to moderate intensity (based upon maximal heart rate calculations); Intervention II- Infrared Sauna Cabin 45 minutes total [2 x 15-minute sessions separated by 10-15 min cool-down (at room temperature, ~25oC)] of monitored full spectrum infrared sauna activity at 60oC, < 10-20% relative humidity; Intervention III- Finnish-style Sauna 45 minutes total [2 x 15-min sessions separated by 10-15 min cool-down at room temperature, ~25oC) of monitored Finnish-style sauna activity at ~80oC, < 10-20% relative humidity, allowing brief periods of cool water to be thrown on sauna heater rocks if individually chosen and tolerated during the sauna activity. Each intervention will be monitored closely by a registered medical practitioner of > 20+ years clinical experience and conducted at a Brisbane-based athletic facility.