Effects of muscle fatigue on H-reflex excitability in subjects with ME/CFS
Dr Les Wood (right) and his team
Investigator
Dr Les Wood
Institution
Department of Biological and Biomedical Sciences, Glasgow Caledonian University, Glasgow, UK
Aims
One of the cardinal signs of ME is marked muscle ‘fatigability’ or loss of power, often in response to quite minor degrees of exercise. Muscle cramps, twitching and extreme muscle tenderness are also common findings, but very few ME patients have received a proper clinical examination of their affected muscles. Observable muscle abnormalities might be more common than is often supposed. This study will examine how exercise and fatigue can affect muscle activity, by investigating how nerves control the calf muscles, and what happens to this control after exercise.
Methods
The muscle’s response to electrical nerve stimulation will be measured in order to investigate the effects of fatiguing contractions on the excitability of spinal motoneurone pools using the Hoffmann reflex as a tool to measure this. Following a period of exercise to fatigue the calf muscles, the nerve will be stimulated again to observe any effects of the exercise on nerve control. From this initial investigation of the influence of delayed recovery on ‘reflex excitability’, the investigators hope to find out the status of spinal motoneurones in subjects with ME/CFS during the recovery phase following fatigue. The findings may lead to a large programme of research on muscle and nerve function in ME.
