NASA astronauts Sunita Williams and Butch Wilmore have returned to Earth after spending nine months aboard the International Space Station (ISS). The duo initially traveled to the ISS in June last year aboard Boeing’s Starliner on its first crewed mission, which was intended to last only a few days. However, propulsion issues left the spacecraft unfit for return, extending their stay in space.
Upon re-entering Earth’s gravity, the Crew-9 astronauts experienced common health effects associated with prolonged exposure to microgravity—including puffy faces, thinner legs (chicken legs), increased height, and reduced bone density. To aid their recovery, they have now begun a 45-day rehabilitation program designed to help their bodies readjust.
What is the 45-day astronaut rehabilitation program?
This structured program is managed by NASA’s Astronaut Strength, Conditioning, and Rehabilitation (ASCR) team. It includes daily two-hour sessions for 45 days, customized to each astronaut’s specific needs.
The rehabilitation process is divided into three phases:
- Phase 1 (Landing Day) – Focuses on regaining movement, flexibility, and muscle strength.
- Phase 2 – Introduces proprioceptive exercises and cardiovascular training to improve coordination.
- Phase 3 – The longest phase, aimed at restoring full functional ability.
How Microgravity Affects the Human Body
Extended time in microgravity causes fluid shifts, reduced muscle use, and changes in blood circulation, impacting several physiological functions. According to NASA, the heart does not have to pump as hard against gravity, leading to changes in blood volume, pressure, and circulation efficiency. These adaptations can result in weaker muscles, reduced bone density, and altered organ function, requiring structured rehabilitation upon return to Earth.
Additionally, astronauts may experience changes in aerobic capacity, stamina, balance, coordination, and flexibility—making post-space rehabilitation essential for their long-term health.
As Williams and Wilmore undergo their 45-day reconditioning, their recovery will provide valuable insights into the long-term effects of human spaceflight and inform future missions to the Moon, Mars, and beyond.
