The effects of neuromuscular electrical stimulation on quadriceps in COPD

Principal Investigator: Dr Neil Greening

Other Key Staff: Dr Michael Steiner, Ms Lorna Webb, Mrs Carolyn Sandland

Partners Involved: University Hospitals of Leicester NHS trust

Summary:
Impaired skeletal muscle function is an important contributor to exercise limitation in Chronic Obstructive Pulmonary Disease (COPD) and an adverse predictive indicator, independent of lung function. Given that the pulmonary pathophysiology is largely irreversible, interventions targeting the skeletal muscles are appealing. The effectiveness of pulmonary rehabilitation in the stable state is well established and mediated in part through improvements in skeletal muscle function. However, whole body exercise training may be impractical in situations, such as patients with severe ventilatory limitation or during acute exacerbations. The latter is particularly important as the exacerbation represents a time of acute risk to the skeletal muscles because of the combination of several potential adverse factors. A rehabilitation intervention delivered during exacerbations may therefore have the potential to preserve skeletal muscle function and help restore fitness and activity following the event.

This approach is being tested in a large clinical trial of pulmonary rehabilitation during acute exacerbations of COPD (the REACH Trial). The REACH trial is not studying Neuromuscular Electrical Stimulation (NMES) in isolation. Therefore, additional research is needed to provide an understanding of the performance benefits of NMES in COPD in comparison with voluntary resistance training.

This project will study the effect of NMES and voluntary resistance training on one lower limb in patients with COPD in the stable state using novel techniques for the measurement of skeletal muscle morphology, inflammation and architecture. Alterations in these outcomes will be linked to changes in muscle function resulting from the interventions.

Aims:

• To find out what the adaptations are in skeletal muscle structure, inflammation, and architecture resulting from NMES compared to the untrained limb
• To find out how these adaptations differ from those seen following lower limb voluntary resistance training
• To find out how these intramuscular adaptations relate to changes in muscle function following NMES and voluntary resistance training

Further information:
Patients with COPD have been involved in the design of this project. A previous pilot study looking at the effects of NMES on muscle strength on inpatients has previously been presented at the American Thoracic Society in May 2010. For further information please contact This e-mail address is being protected from spambots. You need JavaScript enabled to view it .

Start Date: 01/2011                                                                                                            Expected End Date: 07/2012

Project Outcomes:          

• Primary outcome- change in muscle mass following six weeks of one-sided training (either NMES or resistance training)
• Secondary outcomes- acute inflammatory effects of training, changes in muscle fibre composition, satellite cell activity, validation of laboratory techniques, effects of training on muscle volume and pennation angle, muscle neural response to training, functional (strength) changes following training

The project will help to shed some light on the mechanisms at skeletal muscle level by which any benefits are brought about. It is hoped to increase the understanding on skeletal muscle abnormalities in COPD and allow NMES to be refined and integrated with other training.