Date of Award
Doctor of Philosophy (PhD)
Clinical and Translational Rehabilitation Health Sciences
Hoeger Bement, Marie K.
Despite an increase in our understanding of the pathomechanisms of chronic pain and the advancement of new treatments, pharmacological management of chronic pain remains poor. This presents the need for non-pharmacological treatments and understanding their efficacy and mechanisms in managing pain. The purpose of this dissertation was to examine the effects of isometric exercise on the somatosensory system and other biopsychosocial aspects related to pain in individuals with and without fibromyalgia. The first aim was to determine whether isometric exercise improves pain inhibitory mechanisms and vibration sense. The second aim was to determine what biopsychosocial factors influence pain relief following exercise.In study one, conditioned pain modulation (CPM; a measure of pain inhibitory mechanism) was assessed before and after exercise (submaximal isometric contraction of the knee extensors held for three minutes) and quiet rest in young healthy adults. In study two, CPM and vibration sense were assessed before and after exercise (submaximal isometric contraction of the knee extensors held until exhaustion) and quiet rest in individuals with and without fibromyalgia. In both studies, the influence of biopsychosocial factors (e.g. body composition, physical activity, pain catastrophizing, kinesiophobia, and pain self-efficacy) were assessed. In study one, local hypoalgesia occurred at the exercising muscle while systemic hypoalgesia was much more variable. CPM decreased at the upper trapezius following exercise in those individuals that reported systemic hypoalgesia and was unchanged in those without systemic hypoalgesia. In study two, local and systemic hypoalgesia occurred with exercise. CPM increased at the deltoid following exercise only in those individuals with impaired baseline CPM irrespective of health status (healthy control or fibromyalgia). Vibration sense increased at a site distal from the exercising muscle (i.e. the index finger). Additionally, pain relief following exercise was not influenced by body composition physical activity, kinesiophobia, and pain self-efficacy. The results from these studies suggest that CPM and systemic exercise-induced hypoalgesia may have similar mechanisms, and the biopsychosocial factors measured in these studies did not impact the pain relief following exercise. Thus, exercise may be a good modality to restore descending pain inhibition and improve vibratory sense.