Aim: To compare electromyographic (EMG) activity in young-adult subjects with different breathing types.
Methodology: This study included 50 healthy male subjects with complete natural dentition, and no history of orofacial pain or craniomandibular-cervical-spinal disorders. Subjects were classified into two groups: upper costal breathing type, and costo-diaphragmatic breathing. Bipolar surface electrodes were located on sternocleidomastoid, diaphragm, external intercostal, and latissimus dorsi muscles. Electromyographic activity was recorded during the following tasks: (1) normal quiet breathing; (2) speaking the word 'Mississippi'; (3) swallowing saliva; and (4) forced deep breathing.
Results: Sternocleidomastoid and latissimus dorsi EMG activity was not significantly different between breathing types, whereas diaphragm and external intercostal EMG activity was significantly higher in the upper costal than costo-diaphragmatic breathing type in all tasks (P<0·05; Wilcoxon signed rank-sum test).
Conclusion: Diaphragm and external intercostal EMG activity suggests that there could be differences in motor unit recruitment strategies depending on the breathing type.
Keywords: Breathing types,; Electromyography,; Forced deep breathing; Normal quiet breathing,; Speech,; Swallowing,.