A new study has revealed that Intense workout during long space flights can help astronauts protect their aerobic capacity.
According to the study, a 17 percent overall reduction in V?O2peak by flight day 15 was observed across the study sample, while some astronauts experienced a significant decline in V?O2peak (a dip that rebounded later in the space flight), other astronauts did not experience any substantial change in V?O2peak.
In an effort to protect their aerobic capacity and prepare their bodies, astronauts routinely perform in-flight cardiovascular and strength exercises. But the effect of exercise on astronauts traveling to the ISS was not known because aerobic capacity (V?O2peak) had only been studied in shorter trips, not during and after longer space flights.
To understand whether the routinely prescribed exercise was effectively maintaining V?O2peak, researchers Alan D. Moore Jr., et al., with the National Aeronautics and Space Administration (NASA) Human Research Program followed 14 astronauts (nine men and five women) who traveled on space flights between 91 and 192 days. On average, the subjects exercised 30 minutes a day on five to six days each week at an average intensity of 73 percent of peak heart rate. The research team measured V?O2peak at approximately nine months and three months before launch; on day 15 of the flight; every subsequent 30 flight days; and day one, 10 and 30 following re-entry to Earth.
Interestingly, the astronauts with the highest V?O2peak experienced the greatest reduction in capacity, but according to the authors, this finding should not be interpreted that a high preflight aerobic capacity is undesirable. Although the astronauts with high capacities tended to lose more, they typically remained at higher levels than crew who started at lower levels.