Risk of Reduced Physical Performance Capabilities Due to Reduced Muscle Size, Strength, and Endurance (Muscle Risk)
Exposure to the microgravity environment causes muscle size, strength, and endurance to decline. Based on ISS data, if crew adhere to the exercise schedule and have access to adequate exercise countermeasure systems then on average, they return with minimal losses of muscle size, strength, and endurance. New exploration countermeasures systems will be different from ISS and may not have the capability to support exercise as required to maintain human performance.
On Challenger’s middeck, Mission Specialist Guion “Guy” Bluford, assists Dr. William E. Thornton (out of frame) with a medical test that requires use of the treadmill exercising device designed for spaceflight by the STS-8 medical doctor on Sept. 5, 1983. Forward lockers with data recording units and checklist notebooks are to the left of Bluford. Guy Bluford was the first African-American astronaut to fly into space.
Directed Acyclic Graph Files
+ DAG File Information (HSRB Home Page)
+ Muscle Risk DAG and Narrative (PDF)
Human Research Roadmap
+ Risk of Impaired Performance Due to Reduced Muscle Size, Strength & Endurance
