Background: To date, rehabilitative exercises aimed at strengthening the pharyngeal muscles have not been developed due to the inability to successfully overload and fatigue these muscles during their contraction; a necessary requirement for strength training. Aims: to test the hypothesis that applying resistance against anterosuperior movement of the hyo-laryngeal complex will overload the pharyngeal muscles and by repetitive swallowing will result in their fatigue manifested by a reduction in pharyngeal peristaltic amplitude. Methods: Studies were done in two groups. In group one studies 15 healthy subjects (age: 42±14 years, 11 female) were studied to determine whether imposing resistance to swallowing using a hand-maid device can affect the swallow induced hyo-laryngeal excursion and related UES opening. In group two, additional fifteen healthy subjects (age 56±25 years, 7 female) were studied to determine whether imposing resistance to the antero-superior excursion of the hyo-laryngeal complex induces fatigue manifested as reduction in pharyngeal contractile pressure during repeated swallowing. Results: Analysis of the video recordings showed significant decrease in maximum deglutitive superior laryngeal excursion and UES opening diameter (p<0.01) due to resistive load. Consecutive swallows against the resistive load showed significant decrease in pharyngeal contractile integral (PhCI) values (p<0.01). Correlation analysis showed a significant negative correlation between PhCI and successive swallows suggesting ``fatigue`` p< 0.001, Conclusion: Repeated swallows against a resistive load induced by restricting the anterosuperior excursion of the larynx safely induces fatigue in pharyngeal peristalsis and thus has the potential to strengthen the pharyngeal contractile function.
- Copyright © 2016, American Journal of Physiology- Gastrointestinal and Liver Physiology