When not to do breathing exercises

What's gentle and what isn't

The U.S. National Center for Complementary and Integrative Health (NCCIH) considers relaxation techniques, slow breathing among them, generally safe for healthy people. It adds that people occasionally report negative experiences, such as increased anxiety, intrusive thoughts, or fear of losing control.

Fast breathing and long breath holds are a different matter. In its guidance on yoga, the same center asks newcomers to avoid extreme practices, and it names forceful breathing as one of them.

Check with a health professional first

This isn't a formality. Your care provider knows your situation and this page doesn't. Ask before you start if any of these apply:

• You're pregnant. NCCIH asks pregnant women to talk with their health care providers before practicing yoga, and the same goes for its breathing practices. Fast breathing and breath holds are off the table until you're told otherwise.
• You have a heart or blood pressure condition. Severe high blood pressure is on NCCIH's list of conditions that may call for modifying the practice.
• You have a lung condition, such as asthma or COPD. Some breathing techniques are taught in pulmonary rehab, but your care team is the one to prescribe and adjust them.
• You have epilepsy. Cleveland Clinic notes that breathing deeply and fast can trigger an absence seizure.
• You've had panic attacks or fainting spells. Hyperventilation produces sensations a lot like panic, and the Wim Hof Method's own instructions warn that fast breathing with holds can, in rare cases, lead to loss of consciousness.
• You have glaucoma. It's on the same NCCIH list.
• You live with a psychiatric condition or a history of trauma. NCCIH mentions rare reports of symptoms getting worse with certain relaxation techniques.

What counts as an intense breathing exercise

On this site, an exercise is intense when it involves fast breathing or long holds. Those are Bellows breath (bhastrika), Breath of fire, Kapalabhati, Deep breathing rounds, Ladder 5-10-15-20, and The 1-4-2 ratio. Before you begin, the guide shows a notice with the conditions.

The reason is physiological. Breathing faster or deeper than your body needs lowers the carbon dioxide in your blood. According to Cleveland Clinic, that narrows your blood vessels, including the ones that supply your brain. On top of that, with less carbon dioxide, hemoglobin gives up its oxygen less readily, something physiologists call the Bohr effect. The result is lightheadedness, tingling, and sometimes spasms in the hands.

Measurements bear this out. In a 2015 study of 47 practitioners, estimated blood carbon dioxide fell 25 to 29 percent during kapalabhati. In another, from 2014, oxygen saturation dipped to around 50 percent during the empty-lung holds that follow thirty deep breaths.

Never in water, never while driving

This rule has no exceptions. A report from the U.S. Centers for Disease Control and Prevention gathered the cases of 16 people in New York State, between 1988 and 2011, who drowned or nearly drowned after hyperventilating on purpose or holding their breath underwater. Four died.

The report explains the mechanism: hyperventilating lowers carbon dioxide, which is the signal that tells you to come up for air. Oxygen keeps falling without that warning, and the person loses consciousness underwater.

That's why fast breathing and breath holds have no place in a pool, the ocean, a bathtub, or the shower. Not while driving, either, and not right before. Do them sitting or lying down, never standing, somewhere a dizzy spell can't put you in danger. Slow breathing doesn't belong behind the wheel either: it takes attention the road needs.

When to stop

Stop and go back to breathing normally, without counting, if any of these show up:

• dizziness, lightheadedness, or blurry vision;
• tingling in your hands, your arms, or around your mouth;
• feeling short of breath;
• a pounding heart or chest pain;
• a headache;
• more anxiety than when you started.

When it's an emergency

A breathing exercise isn't first aid. MedlinePlus warns that rapid breathing for no reason, for the first time, may be a medical emergency. If you have chest pain, severe or sudden shortness of breath, fainting, or confusion, call 911 or your local emergency number.

The American Lung Association offers a piece of advice that works for anyone: don't try an exercise for the first time when you're short of breath. Learn it at a calm moment.

What this site doesn't do

This site describes practices. It doesn't diagnose, it doesn't treat, and it doesn't replace any health care. It's written for adults.

If you've read this far and still have doubts about your own situation, the answer is in an appointment, not on a web page. In the meantime, the three gentlest exercises on the site are 4-6 breathing, Belly breathing, and Pursed-lip breathing.