Current gaps Reduced muscle mass, strength and performance in space

1 current gaps

1.1 in microgravity
1.2 in analog environments
1.3 exploration mission operational scenarios

current gaps

despite 4 decades of effort, success in prevention of spaceflight muscle atrophy , skeletal muscle functional deficits has not yet been achieved in every case although progress has been made. gaps in our knowledge have prevented implementing countermeasures program mitigate risks of losing muscle mass, function, , endurance during exposure microgravity of spaceflight, particularly during long-duration missions. there gaps in our knowledge working , living in partial-g environments , effect wearing eva suit has on human performance in such environment.

in microgravity

the major knowledge gaps must addressed future research mitigate risk of loss of skeletal muscle mass, function, , endurance include following:

for humans living in microgravity environment, optimal exercise regimen, including mode(s), intensity, , volume needed minimize or mitigate risk, not known. appropriate exercise prescription must developed , validated during spaceflight.
the types , functional requirements of exercise hardware , comfortable human-to-hardware interfaces needed minimize or mitigate risks not known. such hardware mission-specific , should validated in appropriate environment.
the effect on maintenance of skeletal muscle strength in-flight use of developed advanced resistive exercise device (ared) not known. because of inherent shortcomings in interim device (ired) (maximum achievable load ~300 lbs), have not provided optimal resistance exercise opportunity flight crews. in-flight study utilizing ared essential in determining efficacy of program of combined aerobic , resistive exercise during long-duration microgravity exposure.
the expected composite of mission-specific critical mission tasks , physiologic costs crewmembers during surface eva operations not defined. essential determining human functional requirements , attendant risk(s). level of skeletal muscle loading , aerobic exercise provided surface eva on moon must determined either through modeling or lunar analog studies , validated.
for humans living in partial g environments, optimal exercise regimens, including mode(s), intensity, , volume needed minimize risk, not known. appropriate exercise prescriptions must developed , validated partial g environments.
eva suits known reduce effective maximum forces can generated crewmembers task completion portion of crewmember’s work expenditure lost in resistance inherent suit. suited human performance levels when working in partial g environments not known , represent additional knowledge gap must filled conduct of appropriate research.

in analog environments

to develop needed exercise regimens needed different mission scenarios, analog environments necessary. appropriate analog environments optimizing mission-specific exercise prescriptions , exercise hardware not yet defined.
initially, lunar analog environment necessary determine if activities of daily life in combination anticipated surface eva activities protect skeletal muscle function. outcome of study determine additional modes, intensities, , volumes of exercise needed maintain skeletal muscle function in lunar partial g environment.
the results of lunar analog studies invaluable design , planning of martian outpost mission.

exploration mission operational scenarios

a mission mars or planet or asteroid within solar system not beyond possibility within next 2 decades. extended transit times , distant planetary bodies within context of current cev designs represents formidable challenge life sciences community. knowledge drawn experience , research during long-duration microgravity exposure on iss beneficial in mitigating risks humans during phase. many gaps in our current knowledge living , working long periods on planetary surfaces in partial g environments should filled during lunar outpost missions.