How to Prepare for a Blood Pressure Reading (and Why Not to Breathe Deeply During It)
Get a reading that reflects your usual blood pressure: rest 5 minutes, sit properly, stay quiet and breathe normally. Here is the checklist and the reasons.
By Al Fuentes, breath master and creator of the Breath Interval app.
20+ years teaching people to control their breath, and their state of mind.
Educational content, not medical advice.
· 4 min read
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A good reading is a boring one: rested, seated properly, quiet, and breathing normally. Skip coffee, exercise and cigarettes for half an hour, empty your bladder, then sit still for 5 minutes before you press start.
Below is a full checklist from the American Heart Association, the reasons behind each step, and a clear note on why this site, which teaches slow breathing, asks you not to use it to change a reading.
How should you prepare for a blood pressure reading?
Follow the standard steps that make readings comparable from day to day. The American Heart Association's scientific statement on measurement lists them: avoid caffeine, exercise and smoking for at least 30 minutes, empty your bladder, sit in a chair with your back supported and feet flat, rest for at least 5 minutes, and do not talk or move during the rest period or the reading (Muntner et al., 2019).
Position matters more than most people expect. The same statement reports that crossed legs may raise systolic pressure by 5 to 8 mmHg and diastolic by 3 to 5 mmHg, and that sitting without back support, such as on an exam table, may raise systolic by 5 to 15 mmHg. If the cuffed arm hangs down below heart level, readings come out too high (Muntner et al., 2019).
Why not to breathe deeply during a reading
Slow breathing has a quick, short-lived effect on blood pressure. In a study of 21,563 patients in Japanese clinics, 6 deep breaths over 30 seconds reduced systolic readings more than 30 seconds of quiet rest, for example 9.6 versus 5.9 mmHg in people with untreated hypertension. The researchers concluded that blood pressure should be measured without deep breathing (Mori et al., 2005).
That matters because your clinician uses your readings to make decisions. A number that is artificially low on the day could hide a real problem. The honest goal of a reading is to capture your usual blood pressure, not your best one. Practice slow breathing at another time of day, and let your readings tell the truth.
The checklist, step by step
- 30 minutes before: no caffeine, no exercise, no smoking.
- Empty your bladder. A full bladder can push the reading up.
- Sit in a chair with your back supported. Feet flat on the floor, legs uncrossed.
- Put the cuff on a bare upper arm. Use the right cuff size for your arm.
- Rest your arm on a table at heart level. Palm up, muscles relaxed.
- Sit quietly for 5 minutes. No talking, no phone, no TV. Breathe normally.
- Take two readings 1 to 2 minutes apart. Record both, or the average, with the time.
- Keep the same routine each day. Same arm, same chair, similar times.
If you feel anxious about readings, let the 5 minutes of rest do the work. Ordinary, unforced breathing is exactly right here.
Choosing and using a home monitor
The device matters as much as the routine. The AHA and AMA policy statement recommends validated, automatic oscillometric devices for home use (Shimbo et al., 2020). A validated device has been tested against a standard protocol for accuracy. Ask your pharmacist or clinician how to check whether a model is validated.
Cuff size is the most common problem. The measurement statement explains that the cuff bladder should cover 75% to 100% of your upper arm circumference (Muntner et al., 2019). A cuff that is too small tends to read high. Measure around the middle of your upper arm and choose the matching size.
Upper-arm cuffs are generally preferred. Wrist devices are more sensitive to arm position and are usually reserved for people who cannot use an upper-arm cuff.
Once a year or so, bring your home monitor to an appointment and compare it with the clinic's readings. That way you know your home numbers can be trusted.
If readings make you anxious
Some people find the cuff itself stressful, especially after a few high numbers. A few things help. Keep to scheduled times rather than checking whenever you feel worried. Use the 5 minutes of rest to sit quietly, look out a window, or listen to something calm, while breathing normally. Record what you get and move on, rather than repeating the reading again and again. And remember that the weekly average, not any single reading, is what you and your clinician will look at.
What the research shows
- American Heart Association statement: rest at least 5 minutes, avoid caffeine, exercise and smoking for 30 minutes, back supported, feet flat, no talking (Muntner et al., 2019).
- Posture errors: crossed legs may add 5 to 8 mmHg systolic; no back support may add 5 to 15 mmHg systolic (Muntner et al., 2019).
- 21,563 clinic patients: 6 deep breaths in 30 seconds reduced systolic more than quiet rest, so researchers advised measuring without deep breathing (Mori et al., 2005).
- Home monitoring statement: validated upper-arm devices and a standardized protocol are recommended for home readings (Shimbo et al., 2020).
The takeaway: consistent, rested, normal-breathing readings give your clinician the clearest picture.
Common mistakes
- Measuring right after climbing stairs or coffee. Wait at least 30 minutes.
- Talking during the reading. Chatting can push numbers up. Stay quiet.
- Wrist or arm at the wrong height. Support the arm at heart level.
- Doing a breathing exercise to get a better number. It hides your usual pressure.
- Taking only one reading. Take two and record both.
Who should be careful
- Anyone on blood pressure medication: never adjust or skip a dose because of one reading; share your log with your clinician.
- People who feel dizzy when standing: sit for a moment after the reading before getting up, and mention it to your doctor.
- Anyone who is pregnant: follow your provider's instructions for home readings closely and report high numbers promptly.
- Anyone with a very high reading and symptoms such as chest pain, shortness of breath or weakness: seek urgent care.
- Everyone: home readings are for trends, not single numbers.
Frequently asked questions
How should I breathe during a blood pressure reading?
Breathe normally and quietly. Avoid deep or slow breathing exercises right before or during the reading, since they can make that one reading lower than your usual.
How long should I rest before checking my blood pressure?
The American Heart Association statement recommends sitting quietly for at least 5 minutes before the first reading, without talking or using your phone.
Does crossing my legs change the reading?
Yes. Crossed legs may raise systolic by 5 to 8 mmHg, according to the American Heart Association statement on measurement. Keep both feet flat on the floor.
Should I take more than one reading?
Yes. Take at least two readings 1 to 2 minutes apart and record both, or the average. One reading on its own can mislead.
Is it okay to do my breathing practice on the same day as a reading?
Yes, just keep them apart. Measure first, or wait until your breathing returns to normal and you have rested. Never adjust medication based on a reading without your clinician.
Sources
- Muntner P, Shimbo D, Carey RM, et al. Measurement of blood pressure in humans: a scientific statement from the American Heart Association. Hypertension, 2019;73(5):e35-e66.
- Mori H, Yamamoto H, Kuwashima M, et al. How does deep breathing affect office blood pressure and pulse rate? Hypertension Research, 2005;28(6):499-504.
- Shimbo D, Artinian NT, Basile JN, et al. Self-measured blood pressure monitoring at home: a joint policy statement from the American Heart Association and American Medical Association. Circulation, 2020;142(4):e42-e63.
