Breathing — Patrick McKeown BOLT Score

Nathan Waters
4 min readAug 8, 2019

Breathing — Patrick McKeown BOLT Score

Nathan Waters — Total Health Performance

The body oxygen level test, or BOLT score, is an assessment used by Patrick McKeown to determine relative breathing volume during rest and breathlessness during physical exercise. Patrick said that this has been noted by researchers as far back as 1975.

With the BOLT you hold your breathe until you feel the first natural desire to breathe. This provides useful information on how soon the first sensations of breathlessness take place. By doing a breathe hold this way, you take away things that can influence the test like willpower and determination, so you end up with a more accurate assessment of breathing volume.

This is important to remember when you perform the BOLT on yourself. You stop at your first urge to breathe. Don’t use your willpower to push for longer and longer times, as it won’t give you an accurate measure. Being very competitive myself and working with a lot of athletes this is the biggest challenge of the test.

Performing the test

To perform the BOLT, it is recommended you rest for 10 minutes. You then take a normal breathe in through your nose and a normal breathe out through your nose. You pinch your nose with your fingers to prevent air from entering your lungs, and then time the number of seconds until you feel the first desire to breathe. Patrick explains that these sensations may include the need to swallow or a constriction of the airways, you may feel involuntary contractions of your breathing muscles in your abdomen or throat. Remember the importance of this as BOLT is a measure of how long it takes your body to react to a lack of air, it isn’t a maximal breathe hold.

You then release your nose, breathe in through your nose, and your inhalation at the end of the BOLT should be calm. Record your score and return to normal breathing.

What do the results mean?

A lower BOLT score means you have lower breathing volume and this leads to more breathlessness when you exercise.

On average most people are somewhere around the 20 second mark if the exercise regularly. Anything lower than 20 seconds, there is a good chance you experience blocked nose, coughing, wheezing, disrupted sleep, snoring, fatigue, and excessive breathlessness, according to Patrick. This is something I have found to be true in myself and clients I have tested.

The goal is to increase your BOLT score to 40 seconds or above for optimal health and athletic performance.

When you have a low BOLT score your breathing is noisy, loud, heavy, and irregular. When you are breathing more efficiently with a score of 40 seconds for example, breathing is effortless, calm, quiet, and soft.

How does increasing my BOLT improve my health and performance?

The urge to breathe is caused by a build of carbon dioxide in the blood and a lack of oxygen in the blood when you perform the BOLT. The length of your breathe hold is influenced by how much carbon dioxide you are able to tolerate, or your ventilatory response to carbon dioxide. So, by increasing your ability to tolerate the build up of carbon dioxide better, through breathing exercises, you are able to maintain calm breathing during rest and lighter breathing during exercise.

In his book, The Oxygen Advantage, Patrick also explains that if your BOLT is below 20 seconds, the excessive breathing will lead to a net loss of carbon dioxide which reduces oxygen delivery, and constriction of the blood vessels and airways, resulting in poor sports performance.

What do I do to improve my BOLT and performance?

The easiest thing to do to improve your performance is to simply nasal breathe. This is something I have been telling clients to do for many years now as it also helps to align the jaw, and correct some postural issues, among many other things.

There are also many breathing exercises that you can perform to improve your ability to tolerate carbon dioxide. Most breathing exercises that help you relax are a good place to start. Something as simple as box breathing, where you breathe in for 4 seconds, hold for 4 seconds, breathe out for 4 seconds, and hold out for 4 seconds, can help you begin breathing more efficiently and can help calm down the nervous system. Use something like this after training, or when trying to get to sleep.

Improving your BOLT score is a simple way to improve your health and performance. As an athlete, you can increase performance by focusing on some nasal breathing and a few simple exercises, without very much extra cost to the valuable energy you need to perform your sessions.



Nathan Waters

Strength Coach at THP — Total Health Performance. Former rugby league player.