David St-Jacques, astronaut from Canda, has returned from a trip of 204 days in space. Nasa claims that a human being loses between 20 and 40% of their muscle mass during such a long stay in space. A few weeks of physical therapy are thus to be expected on his end. This story gave us the idea to create a special program in his honor. Discover our program which aims to help you gain mass by using Earth’s gravity only.