Intense exercise during long space flights can help astronauts protect aerobic capacity

September 1, 2014 by Stacy Brooks

Most people don't think much about their aerobic capacity while at work. But for astronauts carrying out missions on the International Space Station (ISS), maintaining their cardiovascular stamina during long space flights is part of the job. They must be prepared to perform physically demanding tasks or emergency maneuvers at any time during flights that can last between three and six months in a weightless environment.

In an effort to protect their aerobic capacity and prepare their bodies, 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 (V̇O2peak) had only been studied in shorter trips, not during and after longer space flights.

To understand whether the routinely prescribed exercise was effectively maintaining V̇O2peak, 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% of peak heart rate. The research team measured V̇O2peak 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.

The research team observed a ~17% overall reduction in V̇O2peak by flight day 15 across the study sample. While some astronauts experienced a significant decline in V̇O2peak (a dip that rebounded later in the ), other astronauts did not experience any substantial change in V̇O2peak. Interestingly, the astronauts with the highest V̇O2peak 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.

"These results provide evidence that, although many astronauts experience a decline in V̇O2peak during ISS missions, use of the hardware aboard the ISS combined with exercise prescriptions of sufficient exercise intensity can be used to effectively prevent decline in ," the researchers wrote.

Explore further: Exercise has benefits, even when it's done in space

More information: "Peak exercise oxygen uptake during and following long-duration spaceflight." Moore AD Jr, J Appl Physiol (1985). 2014 Aug 1;117(3):231-8. DOI: 10.1152/japplphysiol.01251.2013. Epub 2014 Jun 26.

Related Stories

Exercise has benefits, even when it's done in space

March 22, 2012

Astronauts have been taking part in short spaceflight missions since 1961. They have only recently begun to spend significantly longer times in space, with missions extending for months, since the days of the Russian Mir ...

Russia launches cargo ship to ISS

April 9, 2014

Russia successfully launched an unmanned cargo ship to the International Space Station on Wednesday evening after a spaceship carrying three astronauts experienced a technical glitch last month.

How does exercise work in zero-G?

May 29, 2014

Here's the thing about going to the International Space Station: No one can predict what you'll need to do during your six-month stay there. Maybe something breaks and you need to go "outside" to fix it, in a spacesuit. Maybe ...

The heart of an astronaut, five years on

July 22, 2014

The heart of an astronaut is a much-studied thing. Scientists have analyzed its blood flow, rhythms, atrophy and, through journal studies, even matters of the heart. But for the first time, researchers are looking at how ...

Recommended for you

The search for molecular oxygen among cosmic oxygen atoms

July 27, 2015

Oxygen is the third most abundant element in the universe (after hydrogen and helium) and of course it is important: all known life forms require liquid water and its oxygen content. For over thirty years, astronomers have ...

Hubble looks in on a galactic nursery

July 27, 2015

This dramatic image shows the NASA/ESA Hubble Space Telescope's view of dwarf galaxy known as NGC 1140, which lies 60 million light-years away in the constellation of Eridanus. As can be seen in this image NGC 1140 has an ...

Fossil star clusters reveal their age

July 27, 2015

Using a new age-dating method, an international team of astronomers has determined that ancient star clusters formed in two distinct epochs – the first 12.5 billion years ago and the second 11.5 billion years ago.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.