Sauna, Hyperbaric Oxygen, and the Future of Human Performance: Expanding the Tank and Supercharging the Cargo
Introduction: The Search for the Next Edge
From the endurance runner battling late-race fatigue to the injured patient working to recover faster, the pursuit of better performance often comes down to one core challenge: how do we deliver more energy to our cells when they need it most?
Two modalities from very different traditions — sauna bathing and hyperbaric oxygen therapy (HBOT) — provide intriguing, research-backed answers. On the surface, they couldn’t be more different: one uses heat stress to push adaptation, the other uses pressurized oxygen to saturate tissue. But when viewed through the lens of physiology, they represent complementary sides of the same puzzle: one expands the distribution system, the other supercharges the cargo.
Sauna: Expanding the Tank
The Research
Scoon et al. (2007): Six competitive male runners completed three weeks of post-exercise sauna bathing (~30 minutes at ~90 °C). The result was striking: time-to-exhaustion improved by ~32% when compared to control training blocks. Plasma volume increased by ~7%, strongly correlating with performance gains.
Kirby et al. (2020): Demonstrated that sauna use improved heat tolerance and endurance performance even in temperate conditions, with favorable shifts in thermoregulation and cardiovascular strain.
Philp et al. (2022): Ten days of heat acclimation in national-level rowers increased plasma volume and reduced heart rate during performance tests, suggesting similar benefits across endurance sports.
The Mechanism
Repeated heat stress triggers plasma volume expansion, achieved through fluid retention and plasma protein shifts. With more plasma:
The cardiovascular system pumps more efficiently.
Core temperature rises more slowly.
Oxygen and nutrients are distributed more effectively.
The Benefit
For athletes, the expansion of this tank means greater cardiovascular efficiency, reduced submaximal heart rate, and delayed fatigue. For patients, it highlights sauna as a hormetic stressor — a safe, repeatable challenge that strengthens the body’s adaptability over time.
Hyperbaric Oxygen Therapy: Supercharging the Cargo
The Research
At 1.5–2.0 ATA pressure breathing 100% oxygen, hemoglobin becomes fully saturated. The game-changer is that oxygen dissolves directly into plasma. This raises plasma oxygen content up to 10–20 times higher than normal air.
Clinically, HBOT is well-established for diabetic ulcers, radiation injuries, carbon monoxide poisoning, and decompression sickness.
Emerging studies show promise in neurological conditions (TBI, post-concussion), angiogenesis, and even cellular aging. A 2020 pilot trial reported telomere lengthening and reduced senescent cells after 60 HBOT sessions — intriguing, though still early-stage.
The Mechanism
HBOT bypasses the normal limit of hemoglobin saturation by loading oxygen directly into the plasma itself. This allows oxygen to diffuse into areas with poor perfusion or hypoxia — exactly where injured or stressed tissue needs it most.
The Benefit
HBOT is a short-term oxygen supercharger, fueling wound healing, collagen synthesis, and stem cell activity. For patients, it represents a powerful tool for recovery. For athletes, it offers potential (though still unproven) support for tissue repair and recovery from high training loads.
Putting It Together: Tank + Cargo
Here’s the elegant correlation:
Sauna expands the tank. By increasing plasma volume, sauna creates a larger circulatory reservoir to distribute oxygen, nutrients, and waste products.
HBOT supercharges the cargo. By forcing oxygen into plasma, HBOT maximizes the content of that reservoir, ensuring more oxygen reaches tissues.
In simple terms:
Sauna = a bigger river.
HBOT = more oxygen dissolved in that river.
Together, they address both capacity and content of the circulatory system.
Caveats & Context
Sauna’s benefits are adaptive and long-term, requiring repeated exposures over weeks.
HBOT’s effects are immediate but transient, lasting hours to a day.
They operate on different timescales — one builds the foundation, the other provides an acute boost.
Neither replaces the fundamentals: training load management, sleep, and nutrition remain the bedrock of performance and recovery.
Opportunities for Future Research
Combination Trials
Could sauna-induced plasma expansion amplify HBOT’s plasma oxygen loading? If the tank is bigger, does filling it with more oxygen lead to amplified recovery or performance effects?Performance Outcomes
Does pairing sauna and HBOT improve time-to-exhaustion, recovery from back-to-back high-intensity sessions, or resilience in sports demanding both endurance and tissue repair (marathoners, rowers, combat athletes)?Clinical Translation
Could this synergy accelerate rehab in patients with vascular compromise — diabetic ulcers, tendon injuries, or delayed healing?Longevity Science
Both modalities show signals in the longevity space (plasma volume expansion, oxygenation, telomere dynamics). What happens when they’re studied together as part of a systems-based longevity intervention?
Opinion: Systems Thinking for Human Performance
What these modalities highlight is a bigger truth: adaptation is systemic, not siloed.
Sauna stresses the body, teaching it to expand and adapt.
HBOT supplements the system, delivering oxygen in a way biology normally cannot.
Neither is a silver bullet — but together, they exemplify the potential of combining hormetic stressors (sauna) with technological interventions (HBOT) to create a more resilient human system.
As Mukherjee’s Song of the Cell reminds us, cells don’t exist in isolation; they are part of a larger symphony. Similarly, these modalities shouldn’t be studied or applied in isolation. The future lies in exploring how interventions harmonize — tank and cargo, stress and support — to expand human potential.
Works Cited
Scoon, G. S., Hopkins, W. G., Mayhew, S., & Cotter, J. D. (2007). Effect of post-exercise sauna bathing on the endurance performance of competitive male runners. Journal of Science and Medicine in Sport, 10(4), 259–262. PubMed
Kirby, N. V., Lucas, S. J. E., & Lucas, R. A. I. (2020). Intermittent post-exercise sauna bathing improves markers of heat acclimation and temperate-condition endurance performance. European Journal of Applied Physiology, 120(6), 1291–1303. PMC
Philp, A. N., Buchheit, M., & Peake, J. M. (2022). Can ten days of heat acclimation training improve temperate-condition rowing performance in national-level rowers? Frontiers in Sports and Active Living, 4:947701. ResearchGate
Thom, S. R. (2011). Hyperbaric oxygen: its mechanisms and efficacy. Plastic and Reconstructive Surgery, 127 Suppl 1, 131S–141S.
Hachmo, Y., Hadanny, A., et al. (2020). Hyperbaric oxygen therapy increases telomere length and decreases immunosenescence in isolated blood cells: a prospective trial. Aging (Albany NY), 12(22), 22445–22456.