When you spend several weeks or months in space, it is inexorable, you lose muscle tone. Living in microgravity indeed eliminates the efforts, since a simple impulse of the tip of the finger allows you to be sent several meters away.
Thus, it is between 20 or 30% of their muscle mass that astronauts who take turns in the international space station must recover once they return to the ground, despite the daily sports sessions compulsory for passengers on the ISS. , the International Space Station, sessions optimized over the years thanks in particular to the studies carried out on site, as Thomas Pesquet did during his first stay in 2016.
Now, let’s imagine an even longer trip, towards Mars, or at least a long month to make the trip, a few on the spot, and as many to return, on board a ship which will probably not have the space. to carry weight machines. How do you keep a crew in top physical shape?
This is where an animal comes in…
There is an animal that spends long months inactive, and yet does not lose or loses very little muscle capacity: it is the brown bear! During its hibernation period, which lasts an average of 6 months, this plantigrade hardly loses a hair of muscle! And when he wakes up after this long break, without eating, drinking or moving, he can immediately frolic as if nothing had happened! Unraveling its mystery could therefore help us.
This is what researchers like the French biologist, Fabrice Bertile, are working on. In two ways: by taking samples from bears, during and outside hibernation, to compare them and observe what is happening at the cellular level in the muscle fibers of the sleeping animal.And then some bear serum, the liquid part of blood, was also put in the presence of human muscle cells, to see if it had any effect on them. Results : that works !
The cells were as if boosted…
Scientists must now go into the detail of the composition of this serum to find which molecules in particular act, to find out their modes of action, and their degree of effectiveness. So many more years of research. Work that could also be used in other cases of muscular atrophy, such as in patients who have to stay in bed for a long time.
