Nasal dilators worn by athletes to expand their nasal passageways and allow greater airflow have been found to have no effect on the resistive components of breathing, and therefore, no effect on performance (Medicine & Science in Sports & Exercise 33: 454, Mar. 2011). Some athletes use the nasal dilators in the hopes of reducing the work needed to breathe and, thus, increase the energy available for performance.
The study, conducted by Florida Atlantic University, measured the work performed by the respiratory muscles during exercise to see whether wearing a nasal dilator reduced the work. Fourteen participants, ages 20 to 29, had their pulmonary function tested and then swallowed an esophageal balloon to measure the work of their breathing. Participants were tested in single-blind random order with active and placebo nasal dilators.
Subjects were asked to breathe normally and pedal with increasing amounts of resistance until they felt exhausted.No significant differences were found between the placebo and active nasal dilators on the work of breathing.
Researchers concluded that nasal dilators did not result in any significant alteration in VO2 max, or maximal power output, ventilation or heart rate.