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Chronic obstructive pulmonary disease (COPD) is a heterogeneous chronic lung condition often accompanied by comorbidities and systemic manifestations that affect the person’s clinical condition and prognosis and often require specific treatment. Therefore, the management of COPD extends beyond treatment for the lungs per se. Pulmonary rehabilitation (PR) should be considered as part of person-centered management, and supervised exercise training is a core component of this intervention. PR exercise training parameters (e.g., frequency, intensity, time, and type) should be individualized to maximize each individual’s functional gains while targeting systemic manifestations and comorbidities. This manuscript presents evidence-based tailored recommendations for optimizing exercise interventions for people with COPD and comorbidities that significantly affect prognosis (e.g., mortality, hospitalizations) including cardiovascular disease (CVD) (e.g., chronic coronary syndrome, heart failure), CVD risk factors (e.g., type 2 diabetes mellitus [T2DM], hypertension), and sarcopenia. To achieve these goals, existing guidelines and evidence for exercise training in COPD, CVD, CVD risk factors, and sarcopenia have been reviewed to identify synergies between PR and cardiac rehabilitation, as well as the treatment of T2DM and sarcopenia. In addition, we provided clinical cases to illustrate how PR can be adapted to accommodate specific comorbidities. These examples offer practical guidance for tailoring exercise prescriptions within PR programs to address the unique needs of people with COPD and clinically relevant comorbidities, thereby enhancing overall treatment effectiveness and optimizing health outcomes.

Primary ciliary dyskinesia (PCD) is caused by pathogenetic variants in more than 55 genes. PCD is associated with early-onset chronic wet cough and rhinosinusitis, laterality defects, middle ear disease and reduced fertility. The clinical presentation is heterogeneous, and diagnosis often relies on multiple tests. The American Thoracic Society (ATS) and European Respiratory Society (ERS) have previously developed separate guidelines for diagnosis. Here, ERS and ATS members systematically reviewed the literature on diagnostic tools used in practice and developed unified evidence-based guidelines for PCD diagnosis using Grading of Recommendations, Assessment, Development and Evaluations methodology, and a transparent process of decision-making using evidence-to-decision frameworks. The Task Force panel formulated three PICO (Patients, Intervention, Comparison, Outcome) questions and three narrative questions. The accuracies of high-speed video microscopy, immunofluorescence and nasal nitric oxide were compared to a reference test of transmission electron microscopy and/or genetics. The panel gives a strong recommendation for use of high-speed video microscopy, immunofluorescence and nasal nitric oxide as adjunct tests to transmission electron microscopy and/or genetics for PCD diagnosis. However, no adjunct test is suitable as a standalone test to diagnose PCD and no single adjunct or reference test is suitable to exclude PCD. Pursuing a genetic diagnosis is encouraged owing to the implications for management. The panel emphasises that tests should meet a minimum standard and proposes that patients are evaluated at a referral centre experienced in diagnosis. The pre-test probability based on symptoms should be considered when interpreting results.

Background: Extrapulmonary manifestations including cognitive impairment, reduced muscle and cardiovascular function is common in COPD. While high-intensity exercise offers extrapulmonary benefits, its implementation in COPD is challenging. This randomised cross-over trial examined the feasibility and physiological responses of a novel supramaximal high-intensity interval-training (SupraHIIT) protocol compared to moderate-intensity continuous training (MICT) in people with COPD and matched healthy controls (HCs).

Methods: Sixteen people with COPD and 16 HCs performed SupraHIIT and MICT. SupraHIIT consisted of 10x6 sec intervals at ≈150% and ≈200% of maximum aerobic power (MAP), while MICT was performed for 20 min at 60% of MAP. Outcomes were exercise intensity, change in exerkines, feasibility, and cardiorespiratory demand of the modalities.

Results: SupraHIIT was feasible and enabled up to a 3.5-fold increase in external exercise intensity compared to MICT (184±66 and 245±88 watt versus 71±22 watt in COPD, p<0.001). All participants could complete SupraHIIT which was the preferred modality in both groups (p<0.01) while 5/16 participants with COPD interrupted MICT due to intolerable dyspnea or exhaustion (p=0.005). Both modalities increased plasma brain-derived neurotrophic factor (pBDNF) by an average of 59% (range 30%-87%, p<0.05). When normalised for duration at target power, SupraHIIT produced a 5–10-fold greater increase than MICT. Both modalities lead to a variable response in other exerkines including clusterin, lactate, hepatocyte growth factor and interleukin-6.

Conclusion: In COPD, short duration SupraHIIT is more feasible and enables markedly higher external exercise intensities than MICT. By elevating pBDNF and other potentially beneficial exerkines, it shows potential for extrapulmonary benefits.

Background Cognitive impairment is increasingly recognized as an extrapulmonary manifestation of COPD, yet little is known across cognitive domains and associations with exercise capacities and inflammation remain underexplored.

Aims and objectives: To compare cognitive function in COPD and age-, sex- and physical activity matched healthy controls (HCs) and examine associations with exercise performance and systemic inflammation.

Methods: Multi-domain cognitive function was assessed at baseline in 44 individuals with COPD and 39 matched HCs. Correlations of exercise performance including CPET Wpeak and anaerobic capacity (Borg cycle strength test [BCST Wpeak]) and inflammation were analysed.

Results: COPD participants exhibited lower cognitive function across most domains compared to HCs (Table 1). In COPD, BCST Wpeak correlated with trail making tests ([TMT] TMT-A: r=-.43; TMT-B: r=-.32; p<0.05)) visual processing (VP1: r=.43; p<0.05) and memory (PAL: r=.35; p<0.05), while CPET Wpeak showed no associations. Higher fibrinogen levels correlated with poorer TMT-B and PAL1 performance (r=.38 & r=-.40; p<0.05).

Conclusion: Cognitive impairment spans across multiple domains in COPD, even in those with relatively preserved fitness and lung function. Cognitive deficits were associated to anaerobic, but not aerobic exercise capacity and were associated with systemic inflammation in some, but not all domains.

Accurate prescription of supramaximal exercise requires exercise tests covering the intensity domain between maximal aerobic and peak power output. All-out tests are commonly used for this objective but are considered challenging for people with chronic obstructive pulmonary disease (COPD) due to the extreme physiological demand. The modified Borg cycle strength test (mBCST), previously used in older adults to achieve supramaximal intensities, might be a suitable alternative in people with COPD. We aimed to determine the feasibility of the mBCST in people with COPD and to compare the physiological response with that of healthy older adults. Eighteen people with COPD and 16 age-, sex- and physical activity-matched healthy adults performed a cardiopulmonary exercise test and a mBCST. The mBCST is an incremental test [30 s:30 s cycling:rest; with individualized starting load and step size (15-50 W)] with end-of-test criteria of a rating of perceived exertion of >= 17 or cadence of <75 RPM for >5 s. Feasibility was assessed using a framework covering the aim, interpretability, familiarity, duration, scoring/completion complexity, costs and safety. Measurements of external exercise intensity, rating of perceived exertion, symptoms and cardiorespiratory demand were obtained. The mBCST was deemed feasible according to the feasibility framework. Expressed relative to the cardiopulmonary exercise test, all participants reached supramaximal external exercise intensities during the mBCST [COPD, 145 (125-168)%; healthy, 154 (148-163)%], without differences in intensity or physiological response between groups (p > 0.05). The mBCST is feasible in people with COPD and enables supramaximal external exercise intensities, with similar physiological response to healthy older adults. The mBCST could be considered when selecting an exercise test to prescribe supramaximal exercise.

Background: A novel concept of controlled, short-duration supramaximal HIIT enables 3-4 times higher exercise intensities with reduced dyspnea, compared to moderate-intensity continuous training (MICT) in people with COPD. However, its effects on neurotrophic factors and brain health are yet to be investigated. We aimed to examine the acute response of neurotrophic factors to supramaximal HIIT and MICT in people with COPD.

Methods: Sixteen people with mild to severe COPD (75±6 years; 73±13 FEV1%pred) underwent supramaximal HIIT (comprising 10x6 sec intervals interspersed with 54 sec rest) and MICT (20 min at 60% CPET Wpeak). Supramaximal HIIT was performed at two intensities (HIIT60% and HIIT80%). We measured plasma levels of brain-derived neurotrophic factor (BDNF), irisin, cathepsin B and clusterin pre- and post- exercise.

Results: BDNF increased after both HIIT and MICT (Fig 1). Clusterin increased during HIIT80% (19940 [−35900 to 49600] ng/mL, +11%, p=0.01) and MICT (23390 [−5060 to 51010] ng/mL, +12%, p=0.03), but not HIIT60% (−1100 [−10060 to 113600] ng/mL, -1%, p=0.85). No changes were seen in irisin or cathepsin B.

Conclusion: For the first time, we showed that in COPD, supramaximal HIIT induces a similar increase in BDNF as MICT, with half the exercise duration. Supramaximal HIIT might be a viable exercise modality in COPD, while its long-term effects on brain health remain to be investigated.

Background: Beyond being a pulmonary disease, chronic obstructive pulmonary disease (COPD) presents with extrapulmonary manifestations including reduced cognitive, cardiovascular, and muscle function. While exercise training is the cornerstone in the non-pharmacological treatment of COPD, there is a need for new exercise training methods due to suboptimal adaptations when following traditional exercise guidelines, often applying moderate-intensity continuous training (MICT). In people with COPD, short-duration high-intensity interval training (HIIT) holds the potential to induce a more optimal stimulus for training adaptations while circumventing the ventilatory burden often associated with MICT in people with COPD. We aim to determine the effects of supramaximal HIIT and MICT on extrapulmonary manifestations in people with COPD compared to matched healthy controls.

Methods: COPD-HIIT is a prospective, multi-centre, randomized, controlled trial with blinded assessors and data analysts, employing a parallel-group designed trial. In phase 1, we will investigate the effects and mechanisms of a 12-week intervention of supramaximal HIIT compared to MICT in people with COPD (n = 92) and matched healthy controls (n = 70). Participants will perform watt-based cycling two to three times weekly. In phase 2, we will determine how exercise training and inflammation impact the trajectories of neurodegeneration, in people with COPD, over 24 months. In addition to the 92 participants with COPD performing HIIT or MICT, a usual care group (n = 46) is included in phase 2. In both phases, the primary outcomes are a change from baseline in cognitive function, cardiorespiratory fitness, and muscle power. Key secondary outcomes include change from baseline exercise tolerance, brain structure, and function measured by MRI, neuroinflammation measured by PET/CT, systemic inflammation, and intramuscular adaptations. Feasibility of the interventions will be comprehensively investigated.

Discussion: The COPD-HIIT trial will determine the effects of supramaximal HIIT compared to MICT in people with COPD and healthy controls. We will provide evidence for a novel exercise modality that might overcome the barriers associated with MICT in people with COPD. We will also shed light on the impact of exercise at different intensities to reduce neurodegeneration. The goal of the COPD-HIIT trial is to improve the treatment of extrapulmonary manifestations of the disease.

Introduction 

Chronic obstructive pulmonary disease (COPD) is a major global health concern, characterised by ventilatory constraints, decreased cardiovascular fitness and reduced limb muscle function, profoundly affecting patients’ quality of life. Aerobic training plays a crucial role in the treatment of COPD, but the variability in methodologies and incomplete reporting of key components in aerobic training trials limits the assessment of their effectiveness. This systematic review aims to critically evaluate the application of training principles and reporting of key components in aerobic training trials in randomised controlled trials (RCTs) in the COPD literature.

Methods and analysis

The protocol adheres to the Preferred Reporting Items for Systematic reviews and Meta-Analyses Protocol guidelines. The review will include RCTs utilising aerobic training in individuals with COPD. A comprehensive search, following a predefined search strategy will identify studies published from 2007 to 2024 in English from MEDLINE, Embase, CINAHL, CENTRAL and PEDro. Studies including people with COPD and any aerobic training intervention will be included. Two reviewers will independently screen abstracts and titles for inclusion. Two reviewers will independently conduct the screening of full-text documents and data extraction. Study quality will be assessed using the Tool for the assESsment of sTudy quality and bias in Exercise, specifically developed for exercise training studies. The certainty of the evidence will be evaluated using the Grading of Recommendations Assessment, Development and Evaluation approach. A systematic synthesis will be provided, with meta-analyses and meta-regression when appropriate.

Ethics and dissemination

As this review will involve the analysis of published data, ethical approval is not required. The findings of this review will be disseminated through peer-reviewed publications and conference presentations.

PROSPERO registration number CRD42021247343.

Purpose: Patients with abdominal rectus diastasis (ARD) may have muscular functional impairments, but clinics lack appropriate objective assessment tools. The aim was to establish the relative and absolute reliability, and convergent validity, of muscular activity using Surface Electromyography (SEMG) during isometric abdominal muscle strength testing in patients with ARD and controls without ARD.

Methods: Twenty-six patients with ARD were matched for age, sex and BMI with controls without ARD. Participants were tested twice during isometric muscular contractions using SEMG located on six abdominal sites. Mean amplitude, fatigue, and recruitment order were analyzed. Relative reliability was evaluated with Intraclass Correlation Coefficients (ICC), while absolute reliability was estimated by calculating the Standard Error of Measurement and Minimal Detectable Change. Convergent validity was addressed in relation to participant characteristics, functional ability, and symptoms.

Results: Mean SEMG amplitude for all abdominal wall muscle contractions showed moderate to excellent relative test–retest reliability, with ICC values ranging from 0.46 to 0.97. In contrast, fatigue and recruitment order displayed poor to moderate relative reliability in both groups. Absolute reliability measures were generally high. A moderate to high convergent validity (ARD: rho-value 0.41–0.70; Controls: rho-value 0.41–0.75) was observed for mean amplitude in relation to a functional sit-to-stand test, abdominal circumference, BMI, back pain, and quality-of-life.

Conclusions: The results of applying SEMG during isometric abdominal muscle support practicing the method in clinics, although additional development is needed with further standardization and more functional testing. Furthermore, the method demonstrates construct validity in patients with ARD and in age- and sex-matched controls.

High-intensity exercise is essential for optimal development of cardiorespiratory fitness and health. This is, however, challenging for most people with chronic obstructive pulmonary disease (COPD) due to ventilatory limitations, leading to exercise at lower intensities accompanied by suboptimal stress on the cardiovascular and muscular system.

PURPOSE: To compare the acute effects of a novel concept of short-duration supramaximal high-intensity interval training (HIIT) vs. moderate-intensity continuous training (MICT) in people with COPD and matched healthy controls (HC).

METHODS: Sixteen people with mild to severe COPD (75 ± 6 yr; 8 males; 73 ± 13 FEV1%pred; 119 ± 37 W max aerobic power [MAP]) and 14 HC (74 ± 5 yr; 8 males; 106 ± 14 FEV1%pred; 169 ± 38 W MAP) performed HIIT and MICT on a cycle ergometer in a randomized order. HIIT consisted of 10x6s sprints interspersed with 1-min recovery and was performed at two intensities: 60% of max mean power output for 6-sec (MPO6) and 80%MPO6, estimated from the Borg cycle strength test. MICT consisted of 20-min at 60% of MAP, derived from a cardiopulmonary exercise test. Cardiorespiratory parameters, blood lactate concentration, ratings of exertion/symptoms, and exercise modality preference were obtained.

RESULTS: Exercise characteristics and physiological data collected at the end of exercise are shown in Table 1. All HIIT sessions were completed, while 1 in 3 people with COPD did not complete MICT. The HIIT modality was preferred by 13/16 (COPD) and 12/14 (HC).

CONCLUSION: Short-duration supramaximal HIIT was feasible and enabled a 3.5-fold increase in exercise intensity vs. MICT in people with COPD and HC. Notably, despite the higher exercise intensities, the cardiorespiratory demand during HIIT was similar to MICT and clinically relevant reductions in symptoms were seen in favor of HIIT, in people with COPD. Also, >80% of participants preferred HIIT over MICT.