Expiratory Pressure in Healthy Individuals

"Participants will undergo serial expiratory maneuvers using variously-sized circular mouthpieces and a reference ovoid-shaped mouthpiece.~At each maneuver, the maximal expiratory mouth pressure at total lung capacity will be measured, alongside with the degree of neuromuscular activation of the internal oblique and transverse abdominal muscles using surface electromyography.~The Orbicularis Oris strength will also be measured using the Iowa Oral Performance Instrument."