The objective of this document was to standardise published cardiopulmonary exercise testing (CPET) protocols for improved interpretation in clinical settings and multicentre research projects. This document: 1) summarises the protocols and procedures used in published studies focusing on incremental CPET in chronic lung conditions; 2) presents standard incremental protocols for CPET on a stationary cycle ergometer and a treadmill; and 3) provides patients' perspectives on CPET obtained through an online survey supported by the European Lung Foundation. We systematically reviewed published studies obtained from EMBASE, Medline, Scopus, Web of Science and the Cochrane Library from inception to January 2017. Of 7914 identified studies, 595 studies with 26 523 subjects were included. The literature supports a test protocol with a resting phase lasting at least 3 min, a 3-min unloaded phase, and an 8- to 12-min incremental phase with work rate increased linearly at least every minute, followed by a recovery phase of at least 2–3 min. Patients responding to the survey (n=295) perceived CPET as highly beneficial for their diagnostic assessment and informed the Task Force consensus. Future research should focus on the individualised estimation of optimal work rate increments across different lung diseases, and the collection of robust normative data.

Among patients with chronic obstructive pulmonary disease (COPD), those with the lowest maximal inspiratory pressures experience greater breathing discomfort (dyspnea) during exercise. In such individuals, inspiratory muscle training (IMT) may be associated with improvement of dyspnea, but the mechanisms for this are poorly understood. Therefore, we aimed to identify physiological mechanisms of improvement in dyspnea and exercise endurance following inspiratory muscle training (IMT) in patients with COPD and low maximal inspiratory pressure (Pi). The effects of 8 wk of controlled IMT on respiratory muscle function, dyspnea, respiratory mechanics, and diaphragm electromyography (EMGdi) during constant work rate cycle exercise were evaluated in patients with activity-related dyspnea (baseline dyspnea index <9). Subjects were randomized to either IMT or a sham training control group ( n = 10 each). Twenty subjects (FEV = 47 ± 19% predicted; Pi = -59 ± 14 cmHO; cycle ergometer peak work rate = 47 ± 21% predicted) completed the study; groups had comparable baseline lung function, respiratory muscle strength, activity-related dyspnea, and exercise capacity. IMT, compared with control, was associated with greater increases in inspiratory muscle strength and endurance, with attendant improvements in exertional dyspnea and exercise endurance time (all P < 0.05). After IMT, EMGdi expressed relative to its maximum (EMGdi/EMGdi) decreased ( P < 0.05) with no significant change in ventilation, tidal inspiratory pressures, breathing pattern, or operating lung volumes during exercise. In conclusion, IMT improved inspiratory muscle strength and endurance in mechanically compromised patients with COPD and low Pi. The attendant reduction in EMGdi/EMGdi helped explain the decrease in perceived respiratory discomfort despite sustained high ventilation and intrinsic mechanical loading over a longer exercise duration. NEW & NOTEWORTHY In patients with COPD and low maximal inspiratory pressures, inspiratory muscle training (IMT) may be associated with improvement of dyspnea, but the mechanisms for this are poorly understood. This study showed that 8 wk of home-based, partially supervised IMT improved respiratory muscle strength and endurance, dyspnea, and exercise endurance. Dyspnea relief occurred in conjunction with a reduced activation of the diaphragm relative to maximum in the absence of significant changes in ventilation, breathing pattern, and operating lung volumes.

Introduction: To compare acute mechanical and metabolic responses of the diaphragm and rib cage inspiratory muscle during two different types of respiratory loading in patients with COPD. Methods: In 16 patients (age:65±13, 56% male, FEV1:60±6%pred, Pimax:82±5%pred) assessments of respiratory muscle electromyography (EMG), esophageal (Pes) and gastric (Pga) pressures, breathing pattern, and noninvasive assessments of systemic (VO2, cardiac output, oxygen delivery and extraction) and respiratory muscle hemodynamic and oxygenation responses (blood flow index [BFI], oxygen delivery index, deoxyhemoglobin concentration [HHb] and tissues oxygen saturation [StiO2]), were performed under two different conditions of respiratory muscle loading (hyperpnea and loaded breathing).Results: During hyperpnea, breathing frequency, minute ventilation, esophageal and diaphragm pressure-time product (PTP)/min, cardiac output and VO2 were higher than during loaded breathing (P<0.05). Average inspiratory Pes and Pdi per breath scalene (SCA), sternocleidomastoid (SCM), and intercostal muscle activation was higher during loading breathing (P<0.05). Higher Pdi during loaded breathing compared to hyperpnea was due to higher Pes (P<0.05). Diaphragm activation, inspiratory and expiratory Pga and expiratory abdominal muscle activation did not differ between the two conditions (P>0.05). SCA-BFI and oxygen delivery index were lower and SCA-HHb was higher during loaded breathing. Furthermore, SCA and intercostal muscle StiO2 were lower during loaded breathing compared to hyperpnea (P<0.05). Conclusion:Greater inspiratory muscle effort during loaded breathing evoked larger ribcage and neck muscle activation compared to hyperpnea. In addition, lower SCA and intercostal muscles 3 StiO2 during loading breathing than during hyperpnea might indicates a mismatch between inspiratory muscle oxygen delivery and utilization.