Physiologic response to subgravity; mechanics of nourishment and deglutition of solids and liquids.

Abstract : In order to study the mechanics of nourishment during weightlessness, 165 subgravity parabolas were flown in an F-94C aircraft. Twenty-five experimental subjects attempted to drink from an open container, a container fitted with pierced lid and plastic straw, and a plastic squeeze bottle. Observations were made regarding deglutition of solids, including swallowing of both well and poorly masticated boli. Drinking from open containers proved to be more difficult than had been anticipated. Deglutition of liquids or well masticated solids can be accomplished with little or no difficulty in the weightless state.