One day, long after the Earth has fried and the last remaining super-rich humans are floating in low-gravity spaceships or living on Mars, an astronaut will likely turn to another and ask, “So, do you want to go to SoulCycle?”
And, in fact, it will be imperative that they do, according to new research published this week (April 17) in The Journal of Physiology. The evidence supports past findings showing that inactivity spurred from being in a low-oxygen habitat may lead to health problems, including heart, respiratory, skeletal, and nervous system issues. That means space agencies such as NASA, and ambitious companies such as Elon Musk’s SpaceX and Jeff Bezos’ Blue Origin, should consider developing ways to keep space travelers exercising to maintain their health during long voyages.
The problem with inactivity is, physiologically speaking, a microscopic one. Moving takes energy that we get from a critical process called oxidative metabolism. That’s the result of tiny mitochondria inside our cells using oxygen to produce energy. This occurs throughout the body, including in the skeletal muscles, which are what propel our bodies. That important process becomes encumbered, though, in low-oxygen environments.
A stressed oxidative metabolic process is not good for the body, but the new research shows the resulting inactivity can be equally harmful toward a person’s health. Both low oxygen and inactivity are linked to cardiovascular and respiratory diseases, but the study found that inactivity has a greater impact on skeletal muscles.
As part of their work, the researchers studied 11 healthy males who underwent two 21-day bed-rest sessions conducted at the Olympic Sports Center in Planica‐Rateče, Slovenia. The center has a facility that can induce and maintain simulated altitudes on an entire floor of one of the buildings. One session took place in an oxygen-rich (low-altitude) environment, another in a low-oxygen (high-altitude) environment. In both situations, the men were asked to perform knee extension exercises, so the researchers could assess how their bodies were creating and using energy.
The researchers found that while the low-oxygen environment did show signs of causing respiratory issues, it wasn’t enough to translate into functional impairments. That led the researchers to surmise that the added blood flow from the exercise helped to stave off problems that could have been more damaging. The work is still preliminary, but will ultimately help design better best practices for spaceflight, the primary author of the study, Bruno Grassi of the University of Udine, said in a press release.
If more evidence maintains this finding, it could go to show that, even when humans transcend the need to live on Earth, we’ll still need to suffer at the gym.