Tummo

Forceful, belly-driven breathing, followed by holding the breath in with the belly drawn up. Paired with a sense of building heat.

A Tibetan practice, the source Wim Hof drew from. Not something to guess your way through. Worth learning properly first.

For advanced practice, once the basics are familiar.

Rounds 0 = infinite

In other words

Light a small fire low in the belly with forceful breathing, then trap the heat under a lid by holding your breath. Picturing the flame is part of what keeps it burning.

Benefits

Generates measurable body heat
A powerful focus and arousal effect
Trains breath retention and CO2 tolerance

When to be careful

Avoid if pregnant, or if you have uncontrolled high blood pressure, heart disease, epilepsy, or a history of fainting.
Never combine with cold-water immersion or cold exposure without medical clearance and supervision.
Practise sitting down, in a safe space, never standing, driving, or near water.
Stop if you feel dizzy, light-headed, or short of breath.

The science

Studied formally by Herbert Benson at Harvard in the 1980s, who documented Himalayan monks raising their skin temperature by up to 8°C in freezing rooms while drying wet sheets on their bodies. Later work by Kozhevnikov and colleagues, published in PLOS ONE in 2013, showed that the forceful breathing phase raises sympathetic activity and metabolic rate, while the held breath and visualisation that follow appear to recruit the body's thermogenesis pathway, the same one involved in brown fat. The heat this produces is real and repeatable, not a metaphor.

Origin

Codified within Vajrayana Buddhism, specifically the Six Yogas of Naropa (eleventh century), and practised for centuries by monks in Tibet, Bhutan, and Ladakh, often as part of the gtum-mo initiation, where practitioners spend a winter night naked in the snow. The Six Yogas themselves trace back to earlier Indian tantric sources.

How to

Sit cross-legged, spine very straight, hands resting on the knees.
Begin with twenty to thirty forceful belly breaths through the nose, equal force in and out, like Bhastrika.
On the final inhale, fill the lungs completely. Then perform the 'vase': swallow gently, contract the lower abdomen, and hold the breath while imagining heat building below the navel.
Hold for as long as feels comfortable. Exhale slowly. That's one round. Build up to three rounds.

Common mistakes

Skipping the visualisation. The heat element isn't decorative; it appears to help drive the thermogenic response.
Bracing the chest or throat during the vase hold. The pressure should sit low, in the belly.
Going too fast on the bellows phase and losing the equal in-out rhythm.

Dosage

One to three rounds, once a day in the morning. The full sequence takes ten to twenty minutes.

How it compares

Bhastrika

Tummo opens with something close to Bhastrika, then adds the vase hold and heat visualisation. Bhastrika alone is the rev; Tummo is the rev plus the chamber that traps it.

Kapalabhati

Kapalabhati is a fast, thirty-second cleanse with one active phase. Tummo is a twenty-minute structured journey: bellows, hold, and integration, with both a physical and a mental side.