Hyperbaric Oxygen
How it works

Why pressure changes everything: Henry's Law

Henry's Law is simple: the amount of gas dissolved in a liquid increases proportionally with the pressure above it. At normal atmospheric pressure, haemoglobin carries almost all the oxygen in your blood and it is already near saturation. There is almost no dissolved oxygen in plasma.

At 1.5 ATA, the partial pressure of oxygen rises enough to force oxygen into plasma, cerebrospinal fluid, lymph and synovial fluid. These are fluids that haemoglobin-bound oxygen reaches poorly, if at all, especially in areas of inflammation or injury where microcirculation is compromised. At pressure, oxygen gets there anyway.

Ishihara (2019) reviewed the mechanisms of mild hyperbaric oxygen specifically and confirmed that increased peripheral blood flow and oxygen delivery to tissue are observable even at pressures of 1.25 to 1.5 ATA. Bitterman (2009) described oxygen in this context as a drug, one with a specific dose, a therapeutic window, and measurable physiological effects. For someone managing an autoimmune condition where chronic inflammation has impaired tissue perfusion, or recovering from surgery where blood supply to the site has been disrupted, or an athlete with muscle tissue that is running hypoxic between training sessions, this dissolved oxygen is reaching places that have been starved of it. That is where the therapeutic cascade begins.

The hyperoxic-hypoxic paradox and how the cell responds

One of the most counterintuitive findings in hyperbaric research is what happens at the cellular level during repeated sessions. When the body is exposed to elevated oxygen at pressure and then returns to normal atmospheric conditions, the cell perceives this return as relative hypoxia. an oxygen deficit, even though the person is breathing perfectly normal air.

This triggers activation of hypoxia-inducible factor 1-alpha, HIF-1a, a protein that switches on genes involved in cellular repair. HIF-1a drives angiogenesis, cell regeneration, stem cell proliferation and improved mitochondrial function. The mechanism was first described by Hadanny and Efrati in their foundational 2020 paper in Biomolecules, and has since been confirmed at mild pressure specifically, including at 1.5 ATA, the pressure we use at Mind Over Matter. HIF-1a pathway activation and anti-inflammatory effects were both demonstrated at this pressure (Fratantonio et al., 2024; Hadanny and Efrati, 2020).

In practical terms: the body adapts to repeated hyperbaric sessions by building new blood vessels, repairing damaged tissue and upregulating its own repair mechanisms. Fu et al. (2022) reviewed these mechanisms specifically in the context of healthy ageing in Redox Biology, finding that HBOT produces measurable anti-ageing effects at the cellular level through exactly these pathways. Not just during the session, but in the hours and days that follow. This is why a course of sessions produces results that a single session cannot.

Angiogenesis and new blood supply to damaged tissue

Angiogenesis is the formation of new blood vessels. It is one of the most clinically significant long-term effects of hyperbaric oxygen therapy, and it is the mechanism that makes HBOT genuinely different from other anti-inflammatory or recovery interventions.

HBOT stimulates vascular endothelial growth factor. VEGF, the primary signal that triggers new capillary growth into damaged or poorly perfused tissue. It also upregulates nitric oxide, which drives bone marrow to release endothelial precursor cells that migrate to damaged sites and differentiate into new vessel walls. StatPearls, the clinical reference maintained by the National Library of Medicine, describes HBOT as a potent though underutilised tool for angiogenesis, with demonstrated applications for compromised wounds, grafts, soft tissue radionecrosis and conditions where blood supply is the limiting factor in healing (Buckley and Cooper, 2023).

For post-surgical clients, this is the mechanism that matters most. Surgical sites are areas of disrupted circulation. New capillary growth into the site restores the oxygen and nutrient delivery that drives healing. For autoimmune and inflammatory conditions, new blood supply to chronically hypoxic tissue changes the tissue environment at a fundamental level, reducing the inflammatory state that perpetuates the condition rather than just managing its symptoms.

Autoimmune conditions and inflammation regulation

Chronic hypoxia plays a direct role in the pathogenesis of many rheumatic and autoimmune conditions. Inflamed tissue consumes oxygen faster than compromised circulation can supply it. The resulting hypoxic environment drives further inflammatory signalling, creating a cycle that is difficult to break from the outside.

HBOT interrupts this cycle. It downregulates pro-inflammatory cytokines including TNF-alpha. It supports regulatory T-cell function, helping to rebalance immune responses that have become dysregulated. It reduces neutrophil adhesion to vessel walls, an early step in the inflammatory cascade, and increases antioxidant enzyme activity that reduces the oxidative stress driving ongoing inflammatory damage. Zhou et al. (2023) reviewed reactive oxygen species-sensitive mechanisms in inflammation and tissue regeneration, confirming that modulating oxidative stress through therapies like HBOT creates a more favourable environment for tissue repair.

The immune effects extend beyond inflammation regulation. A 2023 study in the journal Life found that mild hyperbaric oxygen exposure significantly enhanced peripheral natural killer cell activity in healthy subjects, suggesting HBOT supports immune surveillance alongside its anti-inflammatory effects (Nisa et al., 2023). A 2025 review in Frontiers in Medicine specifically examined HBOT across rheumatic and autoimmune diseases, finding efficacy rates between 87.5 and 100% across applications including fibromyalgia, rheumatoid conditions and inflammatory bowel disease. A 2024 international multicenter registry study tracking 378 hyperbaric cases across emerging indications found inflammatory bowel disease and related conditions accounted for 25% of cases, confirming that practitioners are already applying HBOT to autoimmune conditions well beyond its established approvals (Chin et al., 2024). The review noted that HBOT addresses the hypoxic component of autoimmune pathology directly, rather than simply suppressing immune function as many pharmacological approaches do.

This distinction matters. Clients managing autoimmune conditions often carry significant pharmacological burden already. HBOT offers a mechanism that works alongside existing treatment rather than competing with it, addressing the tissue oxygen deficit that drives symptom load.

Post-surgical recovery

Surgery disrupts the local blood supply. Swelling, tissue trauma and the healing response itself all compete for the oxygen needed to repair. Standard recovery relies on the body's own circulation to restore perfusion, a process that takes time and is limited by the degree of disruption.

A 2025 randomised controlled trial published in Scientific Reports examined HBOT following total knee arthroplasty. The HBOT group showed significantly reduced muscle damage markers and inflammatory responses compared to controls, with measurable differences persisting at 1, 3 and 14 days post-operatively. Quadriceps muscle strength and range of motion also recovered faster in the HBOT group (Zhang et al., 2025).

The mechanism is the same one that drives wound healing applications: plasma-dissolved oxygen reaches the surgical site regardless of compromised local circulation, the angiogenic response accelerates new vessel formation, and the anti-inflammatory effect reduces the swelling that impairs recovery. If you are considering hyperbaric oxygen post-operatively, speak to your surgeon first.

Athletic recovery: the evidence

The evidence base for HBOT in athletic recovery has grown substantially in the past two years. A 2025 meta-analysis published in Archives of Physical Medicine and Rehabilitation examined 10 studies covering 299 subjects and found that HBOT significantly accelerated recovery from exercise-induced muscle injury across all subgroups tested, including at pressures of 2.0 ATA and below, and at 60-minute session durations (Luo et al., 2025). This directly validates the protocol we use.

The mechanisms behind this are multiple. Elevated plasma oxygen accelerates aerobic lactic acid metabolism, clearing the metabolic waste that drives post-exercise fatigue. Increased oxygen delivery to damaged muscle tissue accelerates the repair cycle. The anti-inflammatory effect reduces the swelling and soreness that limits training frequency.

At the mitochondrial level, the increased oxygen availability activates the electron transport chain more efficiently. Schottlender et al. (2021) reviewed the specific effects of HBOT on mitochondrial function and oxidative stress in Biomolecules, finding that HBOT improves mitochondrial respiration and reduces oxidative damage. the cellular mechanisms behind improved energy production and recovery capacity over repeated sessions. Over repeated sessions this improves the capacity for cellular energy production. Athletes using HBOT regularly report not just faster recovery between individual sessions but improved sustained output across longer training blocks, which is consistent with this mitochondrial adaptation mechanism.

It is worth being honest about the limits of the evidence. HBOT appears most effective for post-exercise recovery rather than for acute performance enhancement before or during exercise. The research suggests using it after training, not before. That is how we position it.

What your SpO2 tells you after a session

We check blood pressure, temperature and oxygen saturation before and after every hyperbaric session at Mind Over Matter. SpO2, blood oxygen saturation, is the metric most directly relevant to hyperbaric oxygen therapy.

After a session at 1.5 ATA breathing 98% oxygen, most clients see their SpO2 reading elevated above their baseline. Some feel this as increased energy, mental clarity or a sense of physical lightness. The reading confirms the session produced a genuine systemic increase in blood oxygen availability, not just at the tissue level during the session, but measurably present in peripheral circulation afterwards.

Over a course of sessions, trends in your pre-session SpO2 and post-session readings reflect how your body is adapting to the protocol. Combined with blood pressure readings, these give us a simple, objective picture of what each session is producing in your physiology.