Extended stays in reduced-gravity environments can cause a number of negative health impacts on the human body. One significant challenge that HRP researchers are working to overcome is the potential for loss of bone density that crewmembers experience after traveling in space.
Without effective countermeasures in place, crewmembers could lose up to 1 to 2% of their overall bone density per month, which is more than twice the amount that the average adult loses in an entire year. Besides bone loss, space travel can contribute to other bone-related health issues, such as increased risk of kidney stones, hip and spine problems, fractures and other injuries, and impaired healing capability. The HRP is addressing these bone health issues on several research fronts. Exercise, nutritional, and pharmaceutical interventions are being tested, developed, and refined for use before, during, and after spaceflight to lessen the impact of space travel and exploration.