Individuals with chronic low back pain (CLBP) may lack coordination between the stabilising and respiratory functions of trunk muscles. The trunk stabilisers compromise breathing to maintain spinal stability, leading to breathing dysfunctions. Maximal voluntary ventilation (MVV) is indicative of the respiratory muscle endurance and strength whereas end-tidal carbon dioxide (PETCO) gives an estimate of breathing patterns that closely reflect the arterial measurement of CO. CLBP has been shown to have a significant effect on respiratory functions. However, the impact has not yet been quantified. Further, there is a dearth of literature comparingrespiratory functions between CLBP and healthy individuals. This study investigates respiratory functions in participants with and without CLBP.