Conclusions: Results show that as the physiologic demands of swallowing deviate from single, small bolus swallows, the integration of the swallowing and respiratory systems change. This may reflect obligate differences in airway protection strategy and prolonged competition for respiratory resources.
Purpose: This study examined alterations in ventilation and speech characteristics as well as perceived dyspnea during sub-maximal aerobic exercise tasks.
Method: Twelve healthy participants completed aerobic exercise-only and simultaneous speaking and aerobic exercise tasks at 50% and 75% of their maximum oxygen consumption (VO2 max). Measures of ventilation, oxygen consumption, heart rate, perceived dyspnea, syllables-per-phrase, articulation rate, and inappropriate linguistic pause placements were obtained at baseline and throughout the experimental tasks.
Results: Ventilation was significantly lower during the speaking tasks compared with the non- speaking tasks. Oxygen consumption, however, did not significantly differ between speaking and non-speaking tasks. The perception of dyspnea was significantly higher during the speaking tasks compared with the non-speaking tasks. All speech parameters were significantly altered over time at both task intensities.
Conclusions: It is speculated that decreased ventilation without a reduction in oxygen consumption implies that utilization of oxygen by the working muscles was increased during the speaking tasks to meet the metabolic needs. A greater ability to utilize oxygen from inspired air is found in individuals who are at higher fitness levels, and therefore these findings may have implications for individuals who must complete simultaneous speech and exercise for occupational purposes (e.g., fitness/military drill instructors, singers performing choreography).