Brutal health tests 'stranded' NASA astronauts go through in 45-day rehab following nine months in space

It was a rescue mission that gripped the world, but after nine months of being left aboard the International Space Station, Sunita Williams and Butch Wilmore are finally back on terra firma.

Although Williams insisted they weren't 'stranded', Elon Musk accused the Biden administration of 'abandoning' the pair of NASA astronauts.

We didn't get a chance to hear their thoughts on what it was like when their eight-day mission turned into 286 days, nor what they felt during their 17-hour flight back to Earth.

While we were warned that Williams, Wilmore, and Crew-9 astronauts Nick Hague and Aleksandr Gorbunov would be carried away on stretchers, it didn't stop onlookers from being shocked by their seemingly frail condition.

Williams and Wilmore are especially in the spotlight having spent so long in space, although their stay falls some way short of Francisco 'Frank' Rubio holding the record for the longest time an American astronaut has spent in space - clocking up 371 days.

Williams and Wimore were helped onto stretchers before being whisked away (NASA)

All four astronauts will now be entered into a brutal rehab regime that will deal with more than just them having 'baby feet' skin.

There could be some lifelong issues due to spending such a long time in space, with osteoporosis, weakened heart muscles, and even an increased possibility of cancer.

NASA's Commercial Crew Program Steve Stich confirmed, "The crew’s doing great," although they were quickly whisked away for medical examinations, then supposedly flown to Houston for further checks and to start their 45-day recovery.

The Astronaut Strength, Conditioning and Rehabilitation (ASCR) group monitors the health of astronauts, pre, mid, and post-flight, with specialist programs designed to help recondition them against the effects of spending so much time without gravity.

NASA reiterates the 45-day rehab is split into three distinct phases. The first focuses on "ambulation, flexibility and muscle strengthening" through low-intensity exercise and physical therapy mainly through low-intensity physical exercises and light physical therapy.

The second adds "proprioceptive exercise and cardiovascular conditioning," and with your time in space leading to a shift in fluid alongside weakening of heart muscles, their cardiovascular fitness is increased through the likes of treadmills and resistance devices. Of course, the astronauts have already been used to undertaking up to two hours of exercise a day on the ISS.

Phase 3 is the longest and "focuses on functional development." This is the one that will try to get Williams and Wilmore back to where they were before blasting off in June 2024 through mid-intensity exercises.

NASA says that the programs are tailored to each individual astronaut based on their post-flight test results, preferred exercise activities, and the duties they undertook while on the ISS. It adds that while most return to (or even exceed) their pre-flight fitness after 45 days, "Some crew members subjectively indicated the need for a longer rehabilitation period."

It concluded: "The current rehabilitation program for returning ISS crew members seems adequate in content but may need to be extended for longer expeditions."

Although we're yet to hear from Williams and Wilmore, we're sure one of the first questions they'll be asked is about how they feel going straight into a 45-day exercise regime. If we were them, we'd just want a double cheeseburger and an XL portion of fries.