Normal Muscular Activity During Swallowing as Measured by Surface Electromyography

Objectives: Speech-language pathologists use surface electromyography biofeedback as a tool to facilitate swallowing treatment, particularly to improve swallowing strength and coordination. The present study sought to establish normative data of swallowing muscular activity as measured by surface electrodes in order to compare the performance of patients with dysphagia to normal swallow performance. Methods: Thirty normal young (18 to 25 years of age) and elderly (60 or more years of age) subjects swallowed 3 bolus volumes (5,10, and 20 mL) in 2 conditions: swallow-to-command and swallow-when-ready. Swallow muscular activity was measured in microvolts with a portable biofeedback unit. Results: There were significant differences between the 2 swallowing conditions in both age groups. Neither age nor bolus volume had a significant effect on the findings. Conclusions: In using surface electromyography biofeedback as an adjunct to swallowing rehabilitation, it may be more beneficial to use swallow-to-command techniques if one is interested in measuring maximum effort, regardless of patient age or volume selected.