Aerobic capacity measures how much physical exertion a person can withstand. Astronauts must be extremely fit to do spacewalks and respond successfully to situations in space.
Researchers found that aerobic capacity in space is related to the intensity of exercise. NASA found that those exercising at normal intensity saw an initial decrease followed by a gradual increase over time.
This research, NASA said, is especially important for physically demanding space-walk activities outside the space station. A spacewalk is said to be the most physically demanding thing astronauts do because of the pressurized resistance of the spacesuit they have to wear.
However, maximum intensity exercise appears better at improving aerobic capacity. Aerobic capacity returned to preflight levels one month after landing, indicating no long-lasting effects on lungs and muscles. Testing both intensities provides a more comprehensive picture, and better documentation of intensity and specific regimens is needed.
The study on Tuesday focused on exercise and the central nervous system, providing insights into a crew member’s aerobic capability while living and working in weightlessness.
Dr. Kjell Lindgren, Bob Hines, and Dr. Jessica Watkins took turns pedaling on an exercise cycle in the U.S. Destiny laboratory module throughout the day and spent almost an hour each working out while attached to sensors.
Future plans call for up to 24 hours per week of extravehicular activity (working outside of a spacecraft) during lunar and Martian missions, however, early evidence suggests this long stretch of activity may be too strenuous.
According to the Cycle Ergometer with Vibration Isolation and Stabilization System (CEVIS) investigation, cycling in space could help improve physical stamina for extended extravehicular activity. The study found that exercise heart rate initially goes up during onboard exercise but approaches preflight levels later on in missions, owing perhaps to the rigorous exercise regimens, including pedaling.
All three astronauts are currently serving as mission specialists on NASA’s SpaceX Crew-4 mission to the International Space Station, which launched on April 27. Lindgren serves as the commander, Hines serves as the pilot and Watkins serves as the mission specialist. As the Expedition 67 crew was busy with human research, the Boeing Company continued to ready its unpiloted Starliner crew ship spacecraft for launch to the International Space Station on May 19.