A huff is a fast breath out through a wide open mouth and throat, used in place of a hard cough. It helps move mucus (phlegm or sputum) from lower in your airways up toward your throat, so you can clear it in a controlled way. Huffing is one part of airway clearance routines such as the active cycle of breathing technique, which a respiratory physio teaches for lung conditions like COPD and bronchiectasis. Use this page as a reminder of a technique your physio has already shown you. It is not a first lesson.

How to do the huff cough

Sit upright in a supportive chair, feet on the floor and shoulders loose. You can rest a hand on your chest, as in the video, to feel the air move.
Do the loosening part of your airway clearance routine first, as your physio showed you. The voice guide says to huff only once the mucus feels ready to clear.
Take a breath in. The voice guide asks for a deep breath, but physios also teach a smaller breath in with a longer, steady huff for mucus lower in the chest, and a deep breath with a short, quick huff once the mucus is higher up. Your physio will tell you which to use.
Keep your mouth and throat open and squeeze the air out steadily and fairly fast with your tummy muscles, as if fogging a pair of glasses. Keep going until your lungs feel empty or the mucus reaches your mouth.
Spit any mucus into a tissue, then go back to relaxed breathing control for a few breaths before the next huff.

What you should feel

A quick, firm push of air from your tummy while your throat stays open, often with a rumble or rattle in your chest as the mucus moves. It should not make you wheeze or leave your chest tight.

Common mistakes

Closing your throat, so the huff turns into a cough.
Huffing so hard that you wheeze or your chest tightens, which the voice guide warns against.
Doing huff after huff with no breathing control in between.
Huffing before the mucus has moved up, which tires you without bringing much up.

How often

Many airway clearance routines use 1 or 2 huffs at a time, always followed by breathing control, within a session of about 10 minutes or until your chest feels clear. When your chest is settled this is often once or twice a day, and more often when you have more mucus. Your physio will adjust this.

Stop and check with your physio if

You suddenly become short of breath, your chest feels tight or heavy, or you are far more short of breath than usual. Stop, rest and use your breathing control. Call emergency services if the breathlessness came on suddenly, your chest feels tight or heavy, your breathing does not go back to normal, you are gasping, choking or cannot get your words out, you have pain that spreads to your arms, back, neck or jaw, you feel suddenly confused or very drowsy, or your lips or skin turn very pale, blue or gray (on brown or black skin this can be easier to see on the palms of the hands). If everything settles quickly, get medical advice the same day before you do these exercises again.
Your fingers or the skin around your mouth start to tingle, or you feel light-headed or spaced out. This can mean you are breathing too fast or too deeply, so stop and let your breathing go back to normal. If it has not settled within a few minutes, get medical advice the same day. If you faint, or the numbness or tingling is on one side of your face or body, call emergency services, even if it goes away.
You cough up blood. Stop the session, and get medical advice the same day for a few spots or streaks in your mucus. If it is more than a few spots or streaks, or you also find it hard to breathe, have a very fast heartbeat or have pain in your chest or upper back, call emergency services.
Chest pain or pressure, dizziness or feeling faint, a racing or irregular heartbeat, or being far more out of breath than the effort should cause.

From the clinic

Airway clearance is best learned face to face. This page explains the general technique only, so with a lung condition, follow the airway clearance plan your own respiratory team set for you. A respiratory physio checks your technique and fits the huffs into a full routine, such as the active cycle of breathing technique or autogenic drainage. If you bring up mucus most days and nobody has taught you how to clear it, ask your doctor about seeing a respiratory physio. A child who needs airway clearance should be taught by their own respiratory team.

If you use an inhaler or nebulizer to open your airways, ask your team whether to take it before a session. Try not to clear your chest straight after a meal. After surgery on your chest or stomach, follow the plan your physio or surgical team gave you for huffing and coughing, including how to support the wound. If you leak urine when you huff or cough, tell your physio or doctor, as this is common and there is help for it. If you are bringing up more mucus than usual, it is thicker or has changed color, or you have a high temperature or feel more tired or breathless than usual, contact your GP or respiratory team the same day and follow your self-management plan if you have one, as this can be a flare-up or chest infection that needs treatment.

If chest pain, pressure or tightness does not ease quickly when you rest, spreads to your arm, neck, jaw, stomach or back, or comes with sweating, feeling sick, feeling light-headed or being short of breath, call emergency services straight away, as this can be a heart attack. If it eases quickly and none of these happen, get medical advice the same day, and do not exercise again until you have been checked. If you faint while exercising, call emergency services, even if you feel fine again quickly.

Written and checked by the PocketPhysio editorial team. Last updated 2026-09-29.

This page is general education, not a diagnosis or a personal treatment plan. If you have pain, an injury or a health condition, see a physiotherapist or doctor before starting new exercises.

Huff cough