Mars travellers face serious health problems, ISS experiment shows

Scientists sent mice to the International Space Station to study how much gravity is needed to maintain muscle health. The experiment results revealed a critical threshold that is of vital importance for both current astronauts and future Mars colonists. During extended time in space, muscles inevitably weaken, posing a serious risk on long-distance missions.

A new experiment conducted at the International Space Station (ISS) sheds light on one of the greatest challenges in space exploration: how to maintain human body health during prolonged weightlessness. Scientists used mice as test subjects, subjecting them to several different artificial gravity levels to find the so-called critical threshold for preventing muscle deterioration.

Why do muscles weaken in space?

When a person spends extended time in space, their muscles inevitably begin to atrophy, meaning they shrink and become weaker. The reason is simple: without the constant resistance of gravity, the body no longer has to work as hard to maintain muscle. This problem has been known for decades, but until now it has not been precisely clear how much gravity is minimally needed to maintain muscle mass.

The new ISS experiment sought to answer this question by testing different gravity levels and observing how the mice's muscles responded to each. The results pointed to a specific threshold, below which muscle mass loss begins to accelerate rapidly.

A major obstacle for Mars missions

The significance of these findings extends far beyond simply improving living conditions on the ISS. Mars has only about 38% of Earth's gravity, meaning that even while on the planet's surface, future Mars inhabitants will face constant health risks if the critical gravity threshold is higher than that level.

Astronauts who currently spend time on the ISS must already do several hours of physical training per day to maintain muscle mass. In the case of a Mars mission, where travel time alone could last half a year, this challenge becomes even more acute.

Science seeks solutions

Scientists hope that the results of the ISS experiments will help develop better training protocols and possible medical solutions, such as drugs or artificial gravity systems in spacecraft. Without such solutions, humans reaching Mars will face several serious health conditions even before they can begin their research work.