After a nine-month period aboard the International Space Station (ISS), NASA astronauts Sunita Williams and Butch Wilmore have begun a rigorous 45-day rehabilitation program designed to restore their physical health and help them readjust to Earth’s gravity.
The astronauts returned on Wednesday March 19, 2025 aboard SpaceX’s Crew-9 mission, landing down safely off the coast of Florida. Their extended stay in space was the result of an unplanned technical failure.
Originally launched on June 5, 2024, aboard Boeing’s Starliner spacecraft for a planned eight-day mission, the astronauts remained aboard the ISS after the spacecraft’s propulsion system malfunctioned, forcing an extended mission and raising public concerns about the reliability of commercial crew vehicles.
Following their extended stay aboard the International Space Station (ISS), the astronauts will now undergo physical reconditioning to counteract the effects of prolonged weightlessness.
Microgravity affects various aspects of an astronaut’s body, including aerobic capacity, muscle strength, endurance, stamina, balance, coordination, bone density, and neuro vestibular function.
To help them recover, NASA’s Astronaut Strength, Conditioning, and Rehabilitation (ASCR) specialists have designed a customized reconditioning program that begins immediately after landing. The rehabilitation process involves two-hour daily sessions, seven days a week, for 45 days. These sessions are tailored to each astronaut’s specific needs based on medical evaluations and mission roles.
The program is divided into three phases. The first phase, starting immediately after landing, focuses on mobility, flexibility, and muscle strengthening. The second phase adds proprioceptive exercises and cardiovascular training, while the third phase, the longest, prioritizes functional development to help the astronauts regain full physical capability.
NASA experts emphasize that the program not only helps astronauts recover but also prevents long-term health complications.
“The effects of microgravity on the human body are profound,” said Dr. Jeff Davis, a NASA medical officer. “Rehabilitation is essential to ensure astronauts return to their peak physical health and are ready for future missions.”
In some cases, astronauts have even surpassed their pre-flight fitness levels after completing the rehabilitation process. While recovery can be challenging, Williams and Wilmore’s dedication to the program will be crucial as they work toward regaining their strength and endurance.
Their unplanned extended stay in space also offers insight into the complexities of human space travel. Although their mission was originally intended to last eight days, the technical failure with the Starliner spacecraft forced a prolonged stay, drawing attention to both the risks of space travel and the resiliency of astronauts in the face of unexpected challenges.
As Williams and Wilmore embark on their physical recovery, their experience serves as a reminder of the importance of preparation, flexibility, and recovery in the future of human space exploration.
