Suppression of sickness by controlled breathing during mildly nauseogenic motion.

INTRODUCTION: Anecdotal reports from aviators indicate that controlled breathing is used as a countermeasure for motion sickness. We report a trial on the effectiveness of focused, regular breathing on motion sickness.

METHODS: Experiment 1 compared the effects of controlled breathing vs. a counting task on subjective ratings of motion sickness and associated symptoms (n = 12). Experiment 2 investigated the effects of attention (n = 12) on these measures by comparing the counting task with no task. Motion sickness was induced by whole body pitch oscillations (0.2 Hz, +/- 20 degrees peak amplitude) while subjects viewed a video image of the environment oscillating in 180 degrees counter phase. Subjects performed controlled breathing, counting, or no task from the onset of mild nausea to an endpoint of moderate nausea or 30 min motion exposure, whichever came first.

RESULTS: Experiment 1: The mean time to reach motion endpoint was significantly longer (p = 0.01) for controlled breathing (21.3 min) than for counting (15.1 min). Controlled breathing also prolonged the time tolerated with nausea and reduced the recovery time after motion cessation. Experiment 2: The counting task had no effect on baseline motion sickness susceptibility.

CONCLUSION: Controlled breathing may be effective for controlling nausea.