Skeletal muscle strength and endurance in patients with mild COPD and the effects of weight training

Abstract

This study poses two questions: 1) is there an abnormality in isokinetic skeletal muscle strength and endurance in mild chronic obstructive pulmonary disease (COPD)? and 2) what is the effect of a randomized, controlled, 12 week hospital outpatient weight training programme in terms of skeletal muscle function and exercise tolerance?Upper and lower limb isokinetic maximum and sustained muscle function were compared in 43 COPD patients (age 4911 yrs), mean forced expiratory volume in one second (FEV1) 7723% pred and 52 healthy, sedentary subjects (age 51 (10) yrs), mean FEV1 10916% pred. The 43 COPD patients were randomly allocated into training (n=26) and control (n=17) groups. Isokinetic and isotonic muscle function, whole body endurance, maximal exercise capacity and lung function were measured.The COPD patients had reduced isokinetic muscle function (with the exception of sustained upper limb strength) as compared with healthy sedentary subjects. Muscle function improved after weight training in the COPD patients. Whole body endurance during treadmill walking also improved with no change in maximal oxygen consumption.A deficit in skeletal muscle function can be identified in patients with mild chronic obstructive pulmonary disease which cannot be explained by factors such as hypoxaemia and malnutrition. Intervention with weight training is effective in countering this deficit which the authors conclude is probably due to muscle deconditioning. Eur Respir J 2000; 15: 92±97.

Randomised controlled trial of transcutaneous electrical muscle stimulation of the lower extremities in patients with chronic obstructive pulmonary disease

“…Similarly, a 12 week low intensity repetitious exercise of the upper and lower extremities improved endurance of individual muscles but also increased the total work performed on the treadmill. 34 These studies, like ours, show that low intensity muscle training can not only increase the strength of individual muscles, but also exercise tolerance and walking endurance. Our muscle conditioning protocol was similar but more intense than the one used by Simpson and co-workers which required 30 repetitions of knee extension and leg press during each triweekly session.…”

“…10 11 These training exercises have been shown to improve the functional status of these patients. [27][28][29][30][31][32][33][34] Greater improvements in cardiorespiratory fitness have been noted following high intensity training. 30 However, some patients with severe ventilatory limitation may be unable to tolerate high intensity training, especially at the outset.…”

British Thoracic Society guideline on pulmonary rehabilitation in adults: accredited by NICE

“…As such, the GDG reviewed eight RCTs of exercise training versus control 35–42. There were six studies composed solely of resistance training35 36 38 40–42; one study including a combination of aerobic and resistance training39; and one study including mobility training 37. All studies incorporating resistance training demonstrated an increase in muscle strength.…”

Exercise Training Before and After Lung Transplantation

“…Pre-transplant conditions such as COPD are associated with muscle weakness, which can be ameliorated with training. 40,41 Aft er transplantation, strength training can target both muscle weakness and osteoporosis, 40,41 which are secondary eff ects of immunosuppressant medications and inactivity. Muscle strength has been shown to deteriorate rapidly aft er transplant, with one study reporting a mean reduction in quadriceps force of 32% within 0.9 to 2 months following transplantation compared with pretransplant values.…”

“…36 Despite the lack of evidence, the positive eff ects of exercise training in lung transplant candidates have been widely acknowledged in such pre-transplant conditions as COPD, 37 cystic fi brosis, 38 and interstitial lung disease. 39 Individuals with COPD who participate in exercise training benefi t from increased peripheral muscle strength, 40,41 improved endurance, [41][42][43][44][45] decreased dys-pnea, 44,45 a reduced number of exacerbations, 44 and enhanced quality of life. 42,45 Individuals with cystic fi brosis who participated in regular exercise experience improvements in aerobic fi tness, as demonstrated by reduced exercise ventilation and heart rate 46 and a slower decline in pulmonary function.…”