A G-suit, or the more accurately named anti-G suit, 's worn by aviators and astronauts who're subject to high levels of acceleration force ('Gs'). It's designed to prevent a black-out and G-LOC (G-induced Loss Of Consciousness), due to the blood pooling in the lower part of the body when under acceleration, thus depriving the brain of blood. Operation A G-suit doesn't so much increase the G-threshold, but makes it possible to sustain high G longer without excessive physical fatigue. The resting… (More on G-suit)