Anyone who still cannot get back on their feet months after a COVID-19 infection eventually asks the same question: what can IHHT therapy actually achieve for Long COVID – and what do studies say about it? At Vitamin Institute Munich, we have been treating patients with Long COVID, ME/CFS, and burnout with Intermittent Hypoxia-Hyperoxia Therapy since 2021. This article offers an honest overview: what the research shows, what we observe directly in practice – and where the limits of the therapy lie.
IHHT vs. traditional altitude training
If you do not yet know how IHHT works in principle, we recommend first reading our article IHHT vs. traditional altitude training. There, we explain the mechanism of action, the course of a session, and the general indications. This article builds on that basic knowledge and focuses specifically on Long COVID, ME/CFS, and burnout as areas of application.
Why Long COVID is not a normal fatigue syndrome – and why this is crucial for therapy
The core problem in Long COVID is not fatigue in the everyday sense of the word. It is a demonstrably impaired cellular energy production. Since 2021, several independent research groups have shown that affected individuals have structurally altered and functionally impaired mitochondria – the cell structures responsible for producing ATP (energy). An analysis published in 2022 showed these changes in muscle tissue even in people who originally had a mild course of COVID-19.
This explains three clinical features that distinguish people with Long COVID from those experiencing ordinary exhaustion:
- Rest does not restore you – it helps very little: If the body cannot produce energy, it does not recover through rest – just as an empty battery does not recharge simply by being left alone.
- Post-exertional malaise (PEM): Even minor exertion can lead to a crash lasting for days, because the body can no longer efficiently break down the metabolic by-products that are produced.
- Brain fog originates in cellular metabolism: The brain is the body’s greatest consumer of energy. When cellular ATP production drops, cognitive function is affected immediately.
IHHT therapy for Long COVID: what do studies say?
Anyone searching for an IHHT Long COVID study will find a picture that is typical for such a young syndrome: the mechanism-related evidence is strong, but large Long COVID-specific studies on IHHT are still underway. This is not a weakness of the therapy – it is a matter of timing. COVID-19 has only existed since 2020, and randomised controlled studies on treatment approaches take years to conduct.
What the available research shows
- Physical capacity in heart failure and fatigue: Serebrovska et al. demonstrated in randomised studies (2017, 2022) that IHHT significantly improves exercise capacity and cardiac function in fatigued patients. Since poor cardiorespiratory fitness is one of the main features of Long COVID, these findings are directly relevant.
- Cognitive function: Several studies in older patients show measurable improvements in memory, processing speed, and concentration following IHHT courses – functions that are centrally affected in Long COVID-related brain fog.
- Microcirculation: IHHT has been shown to improve capillary circulation and oxygen delivery to tissues. Microvascular damage after SARS-CoV-2 is now recognised as a key mechanism in post-COVID syndrome (Cervia-Hasler et al., Science, 2024).
- Inflammatory markers: Clinical data show a reduction in pro-inflammatory cytokines (including IL-6 and TNF-α) after repeated IHHT applications – relevant because persistent low-grade inflammation is a hallmark of active Long COVID.
- Mitochondrial biogenesis: Burtscher et al. (Redox Biology, 2022) showed that controlled hypoxia-hyperoxia cycles stimulate the formation of new mitochondria and activate antioxidant protective mechanisms – the direct cellular repair mechanism in Long COVID.
The first European pilot studies specifically on IHHT therapy for Long COVID are currently being evaluated. The results available so far are promising. Patients should be aware that final assessment by large RCTs is still pending – and make their decision on that basis.
IHHT for Long COVID – experience from our Munich practice
Studies show mechanisms and group effects. What they do not show is what the course of treatment looks like in the individual case, what mistakes can happen when the therapy is applied incorrectly – and what the decisive levers are in real-life practice. The following picture emerges from our direct patient care since 2021.
Who comes to us?
Most of our patients are between 30 and 65 years old, and many were professionally or physically active before their illness. On average, they come to us around 7 to 14 months after their acute infection – after their GP, internist, and Long COVID clinic have not brought sufficient improvement. The leading symptom is almost always fatigue, combined with at least one additional feature: brain fog, sleep problems, exercise intolerance, or persistent shortness of breath.
What we find in the lab at the beginning
Before the first IHHT protocol, we carry out extended laboratory diagnostics. The result is almost always the same: the standard values are unremarkable – and yet we find measurable deficiencies in almost all patients in coenzyme Q10, magnesium, vitamin D, the B vitamins B1 and B12, as well as ferritin in the suboptimal range. These substances are direct cofactors of mitochondrial energy production. Without them, IHHT may provide the regeneration stimulus for the mitochondria – but the building blocks needed for new, high-functioning structures are missing.
This is the most common reason why IHHT elsewhere does not produce the expected results: the therapy is carried out without accompanying micronutrient diagnostics. We discuss this aspect in detail in our article on micronutrients in Long COVID.
How the course typically develops
We adjust the IHHT protocol after every session based on the actual course of treatment. What we regularly observe:
1
Sessions 1–5
We review your medical history, clarify contraindications, and define your individual therapy goal – whether regeneration, exhaustion, prevention, or performance enhancement.
2
Sessions 6–10
Exercise tolerance increases measurably. Short walks or light everyday tasks become possible again without triggering the typical crash the following day. This step – from “every little thing knocks me out” to “I can do small things again” – is, for most patients, the first noticeable improvement in quality of life.
3
From session 8 onwards
Brain fog and concentration gradually improve. This is the feedback we hear most often – and, from experience, also the improvement patients have been waiting for the most.
Important: not everyone responds in the same way. Duration of illness, severity of mitochondrial dysfunction, and baseline micronutrient deficiencies all influence the result. We do not make blanket promises – we continuously adapt the protocol to the actual development.
T. M., Munich, 41 years old (patient, Long COVID after infection in winter 2023)
“After six months of Long COVID, I was no longer able to work. After ten IHHT sessions at the Vitamin Institute, I finally feel at home in my body again. The brain fog is gone, and my resilience is slowly returning.”
IHHT for burnout and ME/CFS – related syndromes, shared approach
Long COVID is not the only fatigue syndrome in which IHHT therapy is used. Burnout and ME/CFS (Myalgic Encephalomyelitis / Chronic Fatigue Syndrome) share the same biological basis: mitochondrial dysfunction, increased oxidative stress, impaired regulation of the stress axis (HPA axis), and restricted microcirculation. Anyone with one of these syndromes suffers from the same problem on a cellular level – only the causes that led there differ.
In practical terms, this means that the IHHT protocol for ME/CFS and burnout patients differs from that used for competitive athletes or people in preventive medicine. The starting intensity is lower, progression is slower, and monitoring is closer. This is intentional – someone who begins with a severely reduced tolerance for exertion needs a different entry point than someone who wants to optimise endurance.
One special aspect of burnout: IHHT is not a psychological therapy and not a replacement for one. It is a biological foundational therapy – it restores the cellular energy basis on which behavioural therapy and psychotherapy can then work effectively. In cases of burnout, we always recommend a combination of both approaches.
Who is IHHT therapy for Long COVID suitable for – and who is it not suitable for?
Specific contraindications for IHHT in Long COVID – in addition to the general contraindications (see the basic article) – exist in particular in the following cases:
- Acute infections or fever, including during Long COVID flare-ups
- Severe autonomic dysfunction with unstable heart rate variability
- Very low resting oxygen saturation (< 94%)
In such cases, we either begin with an adapted introductory protocol or postpone the start until the patient is stable. The decision is made based on the individual findings during the initial consultation – not according to a checklist.
Frequently asked questions about IHHT therapy for Long COVID
The most common feedback in our practice is improved sleep and more stable energy levels in the morning, often already within the first few weeks. After 8 to 10 sessions, many patients report that light everyday activities are once again possible without triggering the typical crash the next day. Brain fog usually improves gradually in the second half of the course. These are observations from our daily clinical practice – not a guarantee, as individual outcomes vary.
Long COVID-specific RCTs on IHHT are currently underway. What is already available is solid evidence on the mechanisms of action – mitochondrial biogenesis, improved microcirculation, and cytokine reduction – as well as clinical outcomes in comparable fatigue syndromes. A final assessment based on large-scale studies specifically focused on Long COVID is still pending.
Yes. This is one of the key advantages of the therapy: it works at the cellular level without physically straining the body. Patients with pronounced post-exertional malaise who cannot tolerate conventional rehabilitation programmes can usually begin IHHT without difficulty – provided none of the specific contraindications apply.
Because IHHT provides the regenerative stimulus for the mitochondria – but the formation of new, high-functioning mitochondria requires the right building blocks: coenzyme Q10, magnesium, B vitamins, and iron. In almost all Long COVID patients, we find these substances in the laboratory below the functionally optimal range. Without them, the therapy cannot reach its full potential.
IHHT therapy for Long COVID addresses a key issue that many treatment approaches overlook: impaired mitochondrial energy production at the cellular level. The mechanistic research is solid, clinical studies on comparable syndromes show clear improvements, and Long COVID-specific RCTs are currently underway.
What studies cannot fully capture is what we see in practice: IHHT works best when it is individually dosed, supported by laboratory diagnostics, and combined with targeted micronutrient therapy. Anyone starting the therapy without this foundation leaves significant potential untapped.
If you are suffering from Long COVID, ME/CFS, or chronic exhaustion and would like to find out whether and how IHHT may be suitable for you, schedule an initial consultation at Vitamin Institute Munich. We first assess the relevant laboratory findings and then develop an individual treatment concept based on them.
IHHT in Munich – Book your consultation now
Dr Simone Eichinger and the team at Vitamin Institute Munich will guide you individually through your IHHT therapy – scientifically grounded and precisely tailored.
Dr Simone Eichinger – Vitamin Institute Munich
Dr Eichinger is a physician and founder of Vitamin Institute Munich, specialising in preventive medicine, mitochondrial health, and regenerative therapies. She supports patients with IHHT, infusion therapies, and individual health programmes. Learn more about Dr Eichinger→
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