Purpose: The purpose of this study was to investigate the effect of the effortful swallow exercise combined with a sour bolus on lingual strength in adults with dysphagia after stroke. There is research supporting the use of these two interventions separately to improve swallow physiology, but there is limited research available investigating their combined impact on lingual strength. Method: This study used a quasi-experimental case study design. The primary investigator (PI) measured the participant’s tongue strength using the Tongueometer device. The PI instructed the participant to follow a saliva-driven effortful swallow protocol during the baseline phase and a sour bolus-driven effortful swallow protocol during the intervention phase. Results: The participant met the intervention phase criterion of three consecutive data points above the median of the baseline data. However, the percent of non-overlapping data was 66.6%, which is considered questionable at best. None of the intervention phase data points fell outside of the two standard deviation band, thus the results were not considered to be significant. Conclusion: The results must be interpreted with caution given the n of 1, and they cannot be generalized to others in this population. Additionally, several limitations impacted the internal validity. However, the information gauged from this investigation can help guide further research in the much-needed area of dysphagia management.
