How reduced gravity affects astronauts’ muscles and nerve responses

Among the many functions performed by skeletal muscles, an important one is maintaining our posture. If it weren’t for these muscles, Earth’s gravitational pull may make it difficult for us to stand and walk around. The group of muscles—mostly present in our limbs, back, and neck—which are responsible for maintaining our posture and allowing us to move against the force of gravity are rightly called “anti-gravity” muscles.