RESUMEN
OBJECTIVE: Forward head posture lengthens mylohyoid muscles, but its impact on swallowing is unknown. This study determined the effect of sagittal plane neck alignment on surface electromyographic parameters from mylohyoid muscles during oropharyngeal swallowing in healthy, young women. METHODS: Surface EMG over bilateral mylohyoid muscles was recorded in 10 female subjects (22-37 y, Mean = 30 (5.1)) for average peak amplitude (µV). Percent time to peak activity and duration [s] were recorded in three different sitting postures: habitual posture (HP), exaggerated forward head posture (FHP), and optimal posture (OP) with head positioned in alignment with the spine. RESULTS: Paired t-tests revealed that HP produced lower mylohyoid average peak amplitude than the FHP or OP. OP had greater average percent time to peak mylohyoid activity than HP. DISCUSSION: HP yielded the most efficient mylohyoid activity. Muscle activation during swallowing should be addressed when training young women about OP.