Astronauts on long missions at the International Space Station can experience changes to their eyes and vision that can last for years. This study included 20 men who on three separate days at NASA's Johnson Space Center in Houston completed exercises while on their back and tilted back head-first (to simulate the effect of exercise in space); 10 of the participants wore swimming goggles.
Researchers found exercise was associated with decreases in pressure in the eye, while the addition of swimming goggles was associated with modestly increased pressure, which could reduce some of the adverse effects on the eye of long-duration spaceflights. These findings need to be replicated in spaceflight to determine whether increasing eye pressure with swim googles is safe and effective.