Exercise Training in Patients With Mild COPD
Condition: COPD
Study type: Interventional

Summary: 
      The primary aim of this clinical study is to investigate if exercise training can improve
      exercise capacity and quality of life in dyspneic mild chronic obstructive pulmonary disease
      patients.
    

Detailed description: 
      Peripheral muscle mass and function can be impaired in patients with mild chronic obstructive
      pulmonary disease (COPD). Quadriceps cross-sectional area is reduced in these patients
      compared to controls [1], particularly in those with dyspnea as compared to non-dyspneic
      counterparts and smoker controls [2]. Reduced physical activity is closely related to
      peripheral muscle mass in mild COPD [1], suggesting that early therapeutic interventions are
      needed in this group of patients. In addition, reduced quadriceps mass is strongly associated
      to quadriceps weakness [3,4] and a substantial proportion of patients with mild COPD (28%)
      had quadriceps weakness [5]. Reduced muscle mass and resultant muscle weakness contribute to
      limiting exercise in COPD [6-8] and to reduce physical activity, particularly in mild disease
      [1].

      Exercise training (ET) is widely used in patients with moderate-to-very-severe COPD to
      improve peripheral muscle function and thus exercise capacity and quality of life [9].
      Unfortunately, the effects of ET in mild COPD are currently unclear. A recent systematic
      review identified three low-quality studies with different designs (retrospective, one group
      pre-posttest, and one randomized controlled trial) [10]. The authors found significant
      improvements in exercise capacity (effect size 0.87-1.82) and quality of life (effect size
      0.24-0.86) after comparing pretest-posttest data and ET with usual care. Although these
      results are inconclusive and indicate that additional and more robust studies should be
      conducted [10], current recommendations to initiate ET include even mild disease if dyspnea
      or exercise limitation are present [11]. Since peripheral muscle mass and function improve
      with ET [9], the investigators hypothesize that this statement is correct and consequently ET
      will increase exercise capacity in dyspneic patients with mild COPD in comparison to usual
      care.

      Patients will enter an 8-week ET program of 3 days per week supervised exercise training at
      the Rehabilitation Physiotherapy Gymnasium. Exercise training will include high-intensity
      endurance training at 60-80% of baseline peak work rate and strength training of upper and
      lower limbs with 3 sets of 6 repetitions at 50% of one repetition maximum [12,13]. Each
      session will be 60 min duration, 30 min dedicated to cycle exercise. The UC group will
      receive usual outpatient care and follow-up.

      The study will require 30 patients per arm to detect an effect size of 0.88 [10] at the 5%
      significance level and with 80% power, allowing a dropout rate of 30%.
    

Intervention name(s): Exercise training
Intervention type(s): Other
Intervention description(s): 30 min of exercise on a cycle ergometer at 80% of HRmax, 30 min of strength training of upper and lower limbs
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Treatment
Keywords: mild COPD; Exercise training; Six minute walking distance; Quality of life; Saint George Respiratory Questionnaire (SGRQ)