Bone Density

Exercising in space is the most effective way to date to compensate for the relative lack of gravity. However, even with rigorous exercise, astronauts have typically lost up to 0.4-1% of their bone density per month in space. Astronauts could get osteoporosis due to the bone loss they are having. Although astronauts gradually recover their muscle tissue and most of their bone mass when they return to Earth, it is important that they are strong enough to perform strenuous activities in space, such as spacewalks, and emergency procedures during landing. Completing a regular exercise routine in space prepares the astronaut for these situations and also facilitates a shorter period of reconditioning to recover their muscle and bone.