Breath Holding Time and Its Clinical Significance

- Updated on January 8, 2022

By Dr. Artour Rakhimov, Alternative Health Educator and Author

All breathing parameters described above need to be measured using special equipment. Meanwhile, there is a simple test, which can be done at almost any moment by everyone, since only a watch or a clock is required. This is BHT (breath-holding time), or how long one can be without breathing. What are the results of medical studies regarding this test?

According to the textbook “Essentials of exercise physiology” (McArdle et al, 2000), “If a person breath-holds after a normal exhalation, it takes about 40 seconds before breathing commences” (p.252). Breath-holding can be started at different phases of breathing (e.g., after normal inhalation, or exhalation, or taking a very deep inhalation or a complete exhalation). These different conditions can produce large variations in results (by more than 200%). Moreover, sometimes patients are asked to take 2 or 3 deep breaths before the test. Since researchers use different methods for BHT measurements, the standardization of results is necessary in order for them to be compared.

“Handbook of physiology”, after analyzing numerous relevant publications, suggested the following proportions for BHT measurements (Mithoefer, 1965). If BHT after full inhalation is 100%; then BHT after normal inhalation is 55%; BHT after normal exhalation is 40%; BHT after full exhalation is 24%. Taking an additional full exhalation or inhalation before starting the test increases BHT by about 5 or 15% respectively for each full maneuver. This information allows us to compare different BHT tests done during almost a century of clinical investigations if we use some standard conditions for the test. To do that, let me introduce the BHT: BHT is BHT after quiet or usual expiration. The under-line can remind the reader about BHT measured at the base level, as when we are totally relaxed (as after usual exhalation).

Different studies and their results can be now compared by changing their BHTs to the standard of measurements, the BHT. These results are given in Table 1.2.

Warning. Usually, BHT in physiological or medical studies is measured for as long as possible. This procedure is dangerous if you have certain serious health conditions with inflammation, irritation, ulcers, or any other damage to internal organs (this will be fully explained later). The conditions requiring caution include certain heart conditions, diabetes, hypoglycemia, severe kidney disease, gastric or intestinal ulcers, acute gastritis, IBS, panic attacks, migraine headaches, etc.

Types of people investigated	N. of subjects	BHT , S	BHT, s	Test conditions (order of actions just before BHT test)	%BH T for BHT1	Reference
Fit instructors	22	46 s	67 s	Full exhalation, normal inspiration	70%	Flack, 1920
Home defence pilots	24	49 s	72 s
British candidates	23	47 s	69 s
US candidates	7	45 s	66 s
Delivery and	27	39 s	57 s
test pilots – Pilots trained for scouts	15	42 s	62 s
Pilots taken off flying (stress)		34 s	49 s
Normal subjects	30	23 s	58 s	Full inspiration	40%	Friedman, 1945
Neurocirculatory asthenia	54	16 s	40 s
Normal subjects	22	33 s	45 s	Normal inspiration	73%	Mirsky et al, 1946 norm. inspir., alap,
Anxiety states	62	20 s	28 s
Normal subjects, class 1 heart	16	16 s	48 s	Full inspiration, full exhalation, full inspiration	33.3%	Kohn & Cutcher, 1970
Class 2 and 3 heart patients	53	13 s	39 s
Pulmonary emphysema	3	8 s	23 s
Functional heart disease	13	5 s	15 s
Normal subjects	6	28 s	76 s	Full exhalation, full inspiration	38 %	Davidson et al, 1974
Asymptomatic asthmatics	7	20 s	55 s
Asthmatics with symptoms	13	11 s	27 s	Full inspiration	40 %	Perez-Padilla et al, 1989
Normal subjects	14	25 s	74 s	Deep breath of 50% O2, 50% N22	33.3%	Zandbergen et al, 1992
Panic attack	14	11 s	34 s
Anxiety disorders	14	16 s	49 s
Outpatients	25	17 s	43 s	Full inspiration	40 %	Gay et al, 1994
Inpatients	25	10 s	25 s
COPD, CHF (cong. heart	7	8 s	21 s
12 heavy smokers	12	8 s	21 s
Normal subjects	26	21 s	21 s	Normal exhalation	100%	Asmudson & Stein, 1994
Panic disorder	23	16 s	16 s
Normal subjects	30	36 s	36 s	Normal exhalation	100%	Taskar et al, 1995
Obstructive sleep apnea	30	20 s	20 s
Normal subjects	76	25 s	67 s	Full exhalation, full inspiration	38%	McNally & Eke, 1996
Normal subjects	10	38 s	38 s	Normal exhalation	100%	Flume et al, 1996
Successful lung transplantation	9	23 s	23 s
Successful heart transplantation	8	28 s	28 s
Normal subjects	31	29 s	32 s	Normal exhalation in supine position	90%	Marks et al, 1997
Outpatients with COPD	87	8 s	9.2 s

Table 1.2 Breath holding time according to various medical references

Table 1.2 comments.

• 1. “% of BHT for BHT” means the percentage of BHT used to calculate BHT.
• 2. Zandbergen et al, 1992 conducted their experiments with the mixture of 50% O₂ and 50% N₂. According to Ferris with his colleagues (1945), such mixture increases normal BHT by about 50%.

Analyzing the results of Table 1.2, the following conclusions can be made.

• Normal subjects have a longer BHT (maximum pause) in comparison with sick people who suffer from various health problems.
• The stronger the severity of the health problem, the shorter the BHT.
• Recovering and asymptomatic people have intermediate BHT values.

Comments about breath-holding time

Let us now turn our attention to the comments expressed by medical professionals about the breath-holding time of healthy and sick people.

In 1919 The Lancet published one of the first articles describing the medical application of BHT investigated by a military medical doctor and Lieutenant-Colonel Martin Flack (Flack, 1920). As Dr. Flack indicated, less than 35 s BHT was considered to be sufficient to take pilots “off flying through stress” (Flack, 1920). The possible reason for such a drastic measure was described by him on the next page. On one occasion a medical doctor wanted to suspend from flying one experienced pilot due to his unusually low BHT (23 s BHT). The pilot was allowed to fly, lost control, crashed the plane and was killed. The commanding officers decided that this test was, indeed, an indicator of the personal health state, especially stress. At the end of his publication, Flack suggested, “…that these tests would also be of value for measuring trench fatigue, industrial fatigue, and fatigue in women workers…” (Flack, 1920).

According to Dr. Wood, who investigated patients with a variety of symptoms diagnosed as DaCosta’s syndrome (one of the previous names for the chronic fatigue syndrome), low BHT was the most common symptom found in his 200 patients (Wood, 1941).

A few years later Dr. Friedman, Director of the Harold Brum Institute for Cardiovascular Research, San Francisco, after analyzing his patients with neurocirculatory problems wrote, “… the breath-holding time was found to be directly related [inversely proportional] to the severity of the dyspnea suffered” (Friedman, 1945).

Dr. Mirsky and his colleagues (1946) concluded that “the difference [in breath-holding time] between the normal and abnormal patients [with variety of anxiety states] is of clinical significance“.

Two American medical doctors, Robert Kohn, and Bertha Cutcher, in their article “Breath-holding time in the screening for rehabilitation potential of cardiac patients” (Kohn & Cutcher, 1970) described the testing of more than 100 cardiac patients. It was found that “…an individual unable to hold his breath for at least 20 sec [7 s BHT] is a poor candidate for vocational rehabilitation“. Furthermore, “It is now suggested that the determination of the breath-holding time is an effective screening test for rehabilitation potential” (Kohn & Cutcher, 1970).

Apparently, healthy obese patients were “unable to hold their breath much beyond 15 s“, whilst all normal non-obese subjects could breath-hold for more than 30 s (Hurewitz et al, 1987).

Similarly, African researchers noticed that “Significant differences were observed in the mean of the Quetelet index, percent predicted vital capacity and the breath-holding time between the normal female and the obese female subjects. A high but inverse relationship was found between estimated body fat and each percent predicted vital capacity and breath-holding time in subjects whose Quetelet index was above 30 kg/m2” (Sanya &Adesina, 1998)

A review of publications on leprosy (Katoch, 1996) revealed that “respiratory function test studies have shown impaired breath holding time” (abstract).

Authors of the article “Rating of breathlessness at rest during acute asthma: correlation with spirometry and usefulness of breath-holding time” (Perez-Padilla et al, 1989) wrote,

“These results suggest that: 1) magnitude of dyspnea and breath-holding time correlate with severity of airflow obstruction in acute asthma attacks associated with dyspnea at rest; and 2) breath-holding time varies inversely with dyspnea magnitude when it is present at rest” (abstract). Thus, BHT has correlation with the most important parameters officially accepted for the diagnosis of asthma.

Later Mexican scientists published the same result in their article, Estimating forced expiratory volume in one second based on breath holding in healthy subjects. Their conclusion was “FEV1 [forced expiratory volume] can be reliably estimated using BHT” (Nevarez-Najera et al, 2000).

Japanese doctors compared breath-holding times for normal subjects and patients with COPD (chronic obstructive pulmonary disease). “The period of no respiratory sensation [a certain period of no particular respiratory sensation which is terminated by the onset of an unpleasant sensation and followed by progressive discomfort during breath-holding] was also measured in eight patients with chronic obstructive pulmonary disease. The values of the period of no respiratory sensation in patients with chronic obstructive pulmonary disease were apparently lower than those obtained in normal subjects. These findings suggest that measurement of the period of no respiratory sensation can be a useful clinical test for the study of genesis of dyspnoea” (Nishino et al, 1996).

Kendrick and colleagues used breath holding for more accurate measurements of pulmonary blood flow (Kendrick et al, 1989). It was important for testing that the subjects hold their breath as long as possible for better measurements. The researchers had 33 patients with cardiac problems (but without overt cardiac failure) and noticed that, “for very dyspnoeic patients a breath-hold time of less than 10 s would be desirable…e.g., 6 s is acceptable.

However, in very ill patients, even a 6 s breath hold time may be too long” (Kendrick et al, 1989). The authors were clearly disappointed by the short BHTs of their patients.

Magnetic resonance imaging (MRI) is a test in which X-ray films are taken of patients, who must remain motionless during the procedure. Patients must therefore be able to hold their breath for the duration of the test. Sick patients with numerous health problems have been a challenge for MRI professionals since these patients could not hold their breath a sufficiently long enough time in comparison with normal subjects.

For example, one abstract claimed that patients with coronary artery disease “found it significantly more difficult to perform a steady breath-hold … or attain the same diaphragm position over multiple breath-holds than normal subjects” (Taylor et al, 1999).

To solve this problem, new magnetic imaging techniques requiring shorter BHTs (even as short as a few seconds only) were developed. However, some, most seriously ill patients could not achieve even multiple 1 s breath holds, as reported by Posniak and colleagues (1994):

“OBJECTIVE. Chest and abdominal CT scans using 1.0-sec scan times are often limited by motion in patients who are unable to hold their breath. With our scanner, we can obtain images in 0.6 sec (partial scan)” (abstract). The breathing pattern of some patients was so strong that they could not stop for even a single second.

Russian medical Doctor K.P. Buteyko and his colleagues tested thousands of patients with a variety of cardiac and bronchial problems and found that sick people usually have about 10-20 s BHT, and the very sick as low as 3-5 s. With approaching death, the breath-holding time gradually, day after day, goes down: 5 s, 4, 3, 2, 1 (last frantic gasps for more air), death… (Buteyko, 1977).

Are there any health conditions in which BHT is long in spite of poor, but stable health? It is possible, according to my research, in such rare cases as obesity hypoventilation syndrome, chronic mountain sickness, after carotid body resection (these nervous cells monitor carbon dioxide concentration in the blood and brain and, as a result, control respiration), and curarisation of respiratory muscles (a procedure during which respiratory muscles are cut and cannot obey the central nervous system). Obviously, more research is required before final conclusions can be made.

We can see that the BHT (breath holding time after normal expiration) is an excellent indicator of our health. The sicker the person, the lower the BHT.

Finally, it can be noted that these low BHTs were found for sick and severely sick patients. Apparently, there are certain people who have low BHTs (due to chronically heavy breathing) but are not diagnosed (yet?) with any serious organic disease.

References

Flack M, Some simple tests of physical efficiency, Lancet 1920; 196: p. 210-212.

Friedman M, Studies concerning the aetiology and pathogenesis of neurocirculatory asthenia III. The cardiovascular
manifestations of neurocirculatory asthenia, Am Heart J 1945; 30: p. 378-391.

Hurewitz AN, Sampson MG, Voluntary breath holding in the obese, J Appl Physiol 1987 Jun; 62(6): p. 2371-2376.

Katoch K, Autonomic nerve affection in leprosy, Indian J Lepr 1996 Jan-Mar; 68(1): p. 49-54.

Kohn RM & Cutcher B, Breath-holding time in the screening for rehabilitation potential of cardiac patients, Scand J
Rehabil Med 1970; 2(2): p. 105-107.

Nevarez-Najera A, Hernández-Campos S, Rodríguez-Morán M, Guerrero-Romero F, Estimating forced expiratory
volume in one second based on breath holding in healthy subjects [Article in Spanish], Arch Bronconeumol. 2000 Apr;
36(4): p. 197-200.

Nishino T, Sugimori K, Ishikawa T, Changes in the period of no respiratory sensation and total breath-holding time in
successive breath-holding trials, Clin Sci (Lond). 1996 Dec; 91(6): 755-761.

Perez-Padilla R, Cervantes D, Chapela R, Selman M, Rating of breathlessness at rest during acute asthma: correlation
with spirometry and usefulness of breath-holding time, Rev Invest Clin 1989 Jul-Sep; 41(3): p. 209-213.

Posniak HV, Olson MC, Demos TC, Pierce KL, Kalbhen CL, CT of the chest and abdomen in patients on mechanical pulmonary ventilators: quality of images made at 0.6 vs 1.0 sec, Am J Roentgenol 1994 Nov; 163(5): p. 1073-1077.

Sanya AO, Adesina AT, Relationship between estimated body fat and some respiratory function indices, Cent Afr J Med. 1998 Oct; 44(10): p. 254-258.

Taylor AM, Keegan J, Jhooti P, Gatehouse PD, Firmin DN, Pennell DJ, Differences between normal subjects and patients with coronary artery disease for three different MR coronary angiography respiratory suppression techniques, J Magn Reson Imaging 1999 Jun; 9(6): p. 786-793.

Extract from Dr. Artour Rakhimov's Amazon book "Normal Breathing: The Key to Vital Health", also available in PDF.