Negative pressure and muscle activity during discrete sips from high resistance straws.

The purpose of the current investigation was to explore how intra-oral negative pressure and submental muscle activity vary across sips from straws varying in internal diameter and across conditions of low versus high effort. Healthy adults took discrete sips from four straws varying in internal diameter. Sips were performed under normal and high effort conditions. Submental surface electromyography (sEMG) and negative intra-oral pressure were recorded during sips. Significant main effects of straw condition were observed for negative intra-oral pressure. A non-significant trend for increased muscle activity associated with smaller straw diameter was also observed. Significant main effects of effort condition were observed for both submental sEMG and negative intra-oral pressure. The findings are interpreted as supporting the clinical hypothesis that high resistance drinking straws varying in diameter may offer systematic overload to the oral musculature. The findings also support encouraging maximum effort to achieve even further overload.