When patients with chronic obstructive lung disease (COPD) are admitted to the hospital with a severe exacerbation they lose muscle strength. This muscle weakness predisposes these patients to further hospital admissions. Resistance training is a potent countermeasure to prevent and treat muscle weakness. In the setting of an acute exacerbation this intervention however has not been validated.

The present study aims at investigating the safety and efficacy of resistance training (3x8 quadriceps extensions per day) to prevent muscle weakness. End points are quadriceps muscle strength and hospital readmission and functional status at discharge. Using the minimally invasive needle muscle biopsy technique described by Bergström the effects of resistance training on the skeletal muscle will be analyzed in detail.

After giving informed consent, patients will be randomized on admission into usual care or usual care plus resistance training. Patients will be followed-up using the clinical pathway for COPD (10 days). After one month patients will attend the outpatient clinic for a follow-up visit. Besides the measurement prescribed in the clinical path for COPD (including arterial blood gas measures, lung function, functional investigation of the patients), patients will undergo muscle strength measures and venous blood will be drawn for the analysis of systemic inflammatory and growth factors. Half of the patients will receive a resistance training program. At the end of the hospital admission, a needle biopsy of the vastus lateralis muscle will be obtained.

Inclusion criteria:

• COPD exacerbation, admitted to the respiratory units
• Informed consent
• Age < 80
• No critical comorbidity compromising outcome up to one month.
• No suspect of malignancy

Exclusion criteria:

• Patient is involved in a rehabilitation program with a frequency >1/wk during one month after inclusion in the study
• NIMV or ICU on admission
• Patient scheduled for procedure (LTX/LVRS) within one month after discharge
• Readmission <14 days after previous hospitalization
• Significant pathology that would hinder the participation in resistance training (gonarthrosis, arthritis to be judged by the investigator)
• Clinical signs of pulmonary hypertension