You get taller in space: Sunita Williams

Amid concerns over the safe return of NASA astronauts Sunita Williams and Butch Wilmore, an old interview of Williams is going viral over social media.
An interview available on NCERT’s website is being reshared widely. During a visit to India, Williams had interacted with school students where she had discussed how the human body adapts to the microgravity environment in space.
She talked about the rapid growth of fingernails and hair and also said that the height of an individual increases when one is in space.
“Calluses on your feet disappear because you don’t walk, and fingernails and hair grow faster. Without gravity, some wrinkles on your face might go away due to a couple of reasons, one because there is a fluid shift. Your spine also expands because there’s no pressure on the cartilage between your vertebrae, making you slightly taller in space,” she answered a student’s query on how long does it take the body to regain its abilities when astronauts return to the Earth.

“However, these changes reverse once you return to Earth. You can’t escape gravity. You shrink back to your normal height, your back might ache a bit,” she added.
“What we need to really worry about is our bone density and muscle mass because when you are up in space your bones start to leach away. So essentially advanced osteoporosis starts to kick in,” she said and went on to talk about the mitigating techniques which include running on a treadmill with a harness that holds one down. “We also do weightlifting which helps in the hip area and feet area. We do squats with the bar on our back and deadlifts to regenerate the bone density,” she added.
“It takes 24 to 48 hours for the fluid shift to get back to normal,” she added.
Since, under microgravity conditions, there are no gravitational forces that could strain the body-as it would be in space-both the bone density and the mass of muscles deteriorate significantly. On Earth, our bones and muscles are in a state of being pulled down towards the ground by gravity, so doing frequent weight-bearing exercises will keep them strong and dense. This organic stress encourages muscle upkeep and bone remodeling. Since this does not happen to astronauts in space because of the lesser force of gravity, it results in the loss of their muscular mass and bone density.
Since there is no weight to be carried by the bones nor any regular physical activities such as walking and lifting, their bones and muscles are less activated. Due to lesser tension, muscle and bone structures break down a lot faster.
Sunita Williams and Butch Wilmore embarked on Boeing’s Starliner aircraft on June 5. However, due to technical challenges, including helium leaks and multiple thruster failures, the astronaut duo are unable to return to the Earth. As per the latest information, spacecraft will return to the Earth on September 6 with Williams and Wilmore.