Work

Diaphragm Fatigue Does Not Impact Breathing Mechanics or Function in People with Chronic Low Back Pain

Year: 2025

Type: article

Abstract: Background and Objective: The diaphragm is an important respiratory muscle that also plays a crucial role in developing intra-abdominal pressure and assisting in spinal stability. Chronic low back pain (CLBP) is a complex musculoskeletal condition and has been associated with respiratory problems and altered breathing mechanics. The purpose of this comparative cross-sectional study is to investigate whether diaphragm fatigue affects breathing mechanics and function in individuals with CLBP. Methods: Volunteers were recruited between the ages of 35– 65 years old with and without CLBP. Participants performed 30 minutes of exercises intended to fatigue the diaphragm. The following respiratory parameters were measured: Breathing mechanics (chest and abdominal movement and respiratory rate), diaphragm function (forced expiratory volume in 1 second (FEV1) using a handheld spirometer), and diaphragm movement as measured by sub-diaphragm (L1 to diaphragm domes) volume changes at the end of exhalation and inhalation using MRI scans. Results: A total of 36 participants were recruited (n = 21M; n = 15F), with 18 participants suffering from CLBP (n = 10M; 8F) and 18 participants serving as a comparison group (n = 11M; n = 7F). There were no differences in breathing mechanics, diaphragm function or excursion (volumetrics) between people with and without CLBP after 30 minutes of exercises intended to fatigue the diaphragm. Conclusion: The lack of differences suggests that the diaphragm, regardless of its fatigue status as a spinal stabilizer, will not relinquish or weaken its function as a breathing muscle, though it may be less effective as a spinal stabilizer. Individuals with chronic or recurrent low back pain might therefore be more susceptible to subsequent pain flare-ups than non-symptomatic individuals. A potential clinical implication of these findings is that incorporating diaphragmatic breathing exercises to enhance diaphragm function may offer an effective treatment option for patients with CLBP. Plain Language Summary: Why was the study done: The diaphragm is a key muscle for breathing but also stabilizes the spine. A prior study has shown that people experiencing chronic low back pain (CLBP) are more susceptible to diaphragm fatigue as a breathing muscle compared to asymptomatic subjects. This fatigue is thought to potentially lead to a decline in respiratory function and compromise the diaphragm’s effectiveness as a spinal stabilizer. This study was performed to see if the opposite is also true: if the diaphragm is fatigued as a spine-stabilizing muscle, will diaphragm movement and breathing be compromised in people with CLBP? What did the researchers do and find: Thirty-six adults (21 men, 15 women) aged 35– 65, with (10 men, 8 women) and without (11 men, 7 women) CLBP, participated. Participants performed 30 minutes of exercises designed to tire out the diaphragm. Researchers measured breathing patterns (chest and abdominal movement, breathing rate), diaphragm function (using a handheld device to measure air exhaled in one second), and diaphragm movement (using MRI scans to track volume changes during breathing). The breathing patterns and diaphragm function of both groups were compared, but no significant differences were found. What do these results mean: Even when the diaphragm is tired, it continues to work well for breathing, though it may be less effective in supporting the spine. This could mean people with chronic low back pain are more prone to future flare-ups. Keywords: back pain, chronic, breathing, mechanics, functional movement, imaging, diaphragm, spine

Source: Journal of Pain Research

DOI: 10.2147/jpr.s496917

Authors: Ulrike Mitchell, Lindsey Robinson, Jared Brinkman, Dustin Bruening, Anton Bowden, Steven Allen

Institution: Brigham Young University

Language: English

Topic: Musculoskeletal pain and rehabilitation

Subfield: Pharmacology

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $2,836