ArticleERJ open research2023
Reference equations for quadriceps strength, endurance and power: a multicentre study.
Article in ERJ open research, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 8 papers, 1 of them a synthesis that pooled it.
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The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
8 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Effects of exercise on muscle fatigability in COPD: a systematic review and meta-analysis.European respiratory review : an official journal of the European Respiratory Society · 2025Pooled it
- Physical activity coaching programme for people with Long COVID: a pilot randomised clinical trial.Scientific reports · 2026Trial
- The modified Borg cycle strength test (mBCST): Feasibility and physiological response in people with COPD and healthy older adults.Experimental physiology · 2026Article
- Tailored Exercise Prescription for People with COPD and Clinically Relevant Comorbidities: A Consensus Statement of the EXPERT Working Group and Experts in Pulmonary Rehabilitation.Sports medicine (Auckland, N.Z.) · 2026Review
- Pectoral muscle area derived from chest computed tomography to identify quadriceps muscle weakness in COPD.ERJ open research · 2025Article
- Physical Activity and Sedentary Behaviour in People with Long COVID: A Follow-Up from 12 to 18 Months After Discharge.Journal of clinical medicine · 2025Article
- Effect of low-moderate intensity traditional Chinese exercises combined with acupuncture on patients with stable chronic obstructive pulmonary disease: study protocol for a randomized controlled trial.Frontiers in medicine · 2025Article
- Relationship between Volitional and Non-Volitional Quadriceps Muscle Endurance in Patients with Chronic Obstructive Pulmonary Disease.Diagnostics (Basel, Switzerland) · 2024Article
Corrections and comments
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Authors and funding
9 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Introduction: The lack of reference values of lower-limb muscle function hinders the clinical recommendations of its measurement in patients with COPD. Therefore, this study aimed to develop reference equations to predict reference values for quadriceps strength, endurance and power and evaluate their construct validity in patients with COPD. Methods: Quadriceps strength, endurance and power were assessed in 158 healthy individuals and 87 patients with COPD. In addition, patients with COPD performed a 6-min walk test (6MWT) and a 1-min sit-to-stand test (1STS). Multiple linear regressions were performed to develop reference equations. The proportion of patients with COPD with reduced quadriceps function was determined, and correlations between quadriceps strength, endurance and power expressed in percentage of predicted values and 6MWT and 1STS performance were used to document the construct validity of the reference equation. Results: Except for quadriceps isometric endurance, the proposed reference equations explained 50-70% of the variance of the quadriceps properties in healthy individuals. All quadriceps properties were systematically reduced in a large proportion of patients with COPD compared to healthy individuals. Correlation coefficients between quadriceps properties expressed in percentage of predicted values and 6MWT and 1STS performance ranged between 0.28 and 0.49 (all p<0.05). Conclusion: In healthy individuals, age, sex, height and body mass index explained 50-70% of the variance of quadriceps strength, endurance and power. When expressed in percentage of predicted values, these quadriceps properties correlated with 6MWT and 1STS performance, suggesting construct validity of the reference values in patients with COPD.
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