Captain Shubhanshu Shukla, a 39-year-old Indian Air Force pilot turned astronaut, has called his first experience in space as “indescribable.” In his first call from the International Space Station (ISS), Shukla recalled the moments after launch, revealing the physical toll space travel had on him.
“I was not feeling well, and I was very sleepy when we were launched into the vacuum,” he said. “Learning how to walk and eat in space — like a child again,” he added.
Shukla is part of Axiom Mission 4, launched from Florida, along with three other astronauts. The team will spend 14 days aboard the ISS, carrying out scientific experiments and research in microgravity.
What space travel does to the body
While space travel sounds thrilling, it comes with several challenges — especially for the human body. For more than 50 years, NASA’s Human Research Program has been studying how zero gravity affects astronauts during and after their missions.
In space, the absence of gravity causes fluids to shift upwards, increasing pressure in the head and eyes. This can lead to vision problems. Bones, especially those that support body weight, lose 1 per cent to 1.5 per cent of mineral density each month, making them weaker. Muscle mass also reduces faster in space if astronauts don’t follow a strict exercise and diet routine.
“After spending 14 days in space, astronauts often feel weak, tired, and dizzy,” says Dr. Vipul Gupta, Director of Neurointerventional Surgery at Sir H.N. Reliance Foundation Hospital, Mumbai. “They may also lose muscle strength and bone density, which makes bones softer.”
Even though astronauts follow strict exercise routines in space, it’s not always enough to stop these changes.
Astronauts may also experience space motion sickness, which affects balance, coordination, and movement. This happens when the body struggles to adapt to a new gravitational environment.
Common health problems astronauts face after space travel
Once astronauts return to Earth, their bodies need to adjust again to gravity. This can cause several health issues, especially in the first few days.
“Astronauts may feel dizzy, faint, or see black spots. This happens because of something called orthostatic intolerance, where blood pressure and fluid levels drop,” explains Dr. Chaitanya Kulkarni, Consultant, Internal Medicine at Kokilaben Dhirubhai Ambani Hospital, Navi Mumbai.
Here are some of the common problems astronauts may face after landing back on Earth:
- Muscle weakness and joint stiffness
- Bone softening (similar to osteoporosis)
- Balance and walking problems
- Blurry vision or pressure in the eyes
- Trouble sleeping or mood changes
- Higher risk of infections due to low immunity
- Mental stress from staying in a small, closed environment
- Risk of kidney stones due to dehydration and calcium loss
Why astronauts are kept in quarantine after returning back on Earth
Astronauts like Shukla are not allowed to meet people immediately after returning. They are kept in quarantine, monitored closely by doctors, and go through several medical tests.
“Each astronaut is different, so their recovery plans are personalised,” says Dr. Gupta. “Some feel normal within two weeks, but others may take longer to fully adjust.”
How do astronauts recover after space travel?
The recovery process includes:
- Physiotherapy to regain muscle strength and balance
- Heart and blood pressure monitoring
- Eye check-ups to look for any vision problems
- Bone scans to check for loss in bone density
- Mental health support to deal with stress or mood changes
Doctors also use MRI scans and spinal ultrasounds to track bone and muscle changes. Astronauts go through regular fitness tests to check how their heart is functioning after space travel.
