Space travel for long periods of time in microgravity causes changes in the human body. For example, bone cell regeneration slows down, leading to weaker and more brittle bones over time. According to NASA and the Space Station Research Integration Office, if astronauts don’t take precautions and incorporate the right exercises for every month in space, their weight-bearing bones become around 1% less dense.
Exercising in space
Crews on board the space station are required to exercise for an average of two hours a day, from using stationary bicycles to running on treadmills with a harness that adds some gravity-like force. These machines are too big to bring on board spacecraft for longer durations, and astronauts on longer space flights often perform resistance and aerobic exercises.
Muscles weaken over time because they don’t have to work as hard in a low-gravity environment. Researchers have been exploring ways to counteract this bone and muscle atrophy that can have serious health implications, including an increased risk of falls and osteoporosis. Preserving and improving bone, cartilage, and muscle health is a priority in space.
Interesting research
In a study by John Hopkins University, researchers wanted to know if jump-based workouts could help protect astronauts’ knees and improve cartilage health. In this animal study, researchers placed mice on different activity routines using a specialized setup to determine how bounding movements protect and preserve knee tissue. The activity regimens involved repetitive jumping or plyometric training.
The results
Repetitive jumping or plyometric training could preserve the tissue that cushions the ends of bones. The researchers revealed that the jump-trained mice experienced a 26% increase in cartilage thickness and a 110% advantage compared to the restricted-mobility mice. The jump-trained mice also had a 15% gain in bone mineral density.
The benefits of jumping
Jumping movements exert high-impact forces on your joints that can promote healthier joint structures over time. The high-impact forces prompt your knee cells to maintain or enhance the articular cartilage, which is the protective layer over the ends of your bones in the synovial joints. Cartilage prevents your bones from grinding against each other, so it’s especially important in weight-bearing joints like your knees and hips.
Jumping and movement help promote the supply of nutrients, blood, and oxygen to your joints.
Jumping in space
Studies in humans are the next step, but this research on jumping exercises is encouraging. The researchers determined that jumping exercises are promising for boosting and preserving knee health and cartilage thickness up in space.
