WRITTEN BY DIANA MAZZELLA
PHOTOGRAPHED BY MARK MULLIGAN
Judith Hayes is a leader in space physiology at NASA during a turning point for the agency: a U.S. astronaut has just lived in space for nearly one year.
When astronaut Scott Kelly landed back on Earth on March 1 after his year on the International Space Station, he had spent more total time in space — 520 days — than any other U.S. astronaut.
Hayes, BS ’82, MS ’83, Exercise Physiology, heads the Biomedical Research and Environmental Sciences Division at Johnson Space Center in Houston, Texas. She’s spent more than 30 years at NASA discovering what happens to the human body in space and how to help these hardiest of humans recover. When people go into space, their “anti-gravity” muscles in the legs, abdomen and back break down. After just five days it’s apparent by looking at their muscle fibers that living in microgravity is slowly altering their physical forms.
What does that look like at three months? Six months? A year?
When Hayes started at NASA in 1984, there weren’t answers to those questions.
So she and her team found those answers. She established the Exercise Physiology Laboratory at Johnson Space Center in 1987. There, scientists hunted through the “terrestrial literature,” as they call non-space research, in preparation for the mission that eventually became the International Space Station. And beyond NASA’s three Skylab missions and a few Russian trips, there wasn’t much to go on. So they designed tests for the astronauts spending up to 17 days on Space Shuttle missions. And they ran studies where humans spent months in bed to mimic the physiological effects of microgravity.
Hayes’ early design of the space station exercise programs for astronauts are still in use today: a mixture of treadmill, cycle ergometer and resistance exercises. An astronaut in space gets 2.5 hours to exercise, the second-largest chunk of an orbit crew member’s time in their schedule after sleep.
Hayes’ work has helped astronauts stay in top physical shape so they can survive long-term in microgravity and succeed in their missions. On Earth, we’ve benefitted from NASA’s biomedical efforts in developing telemedicine and medical advances relating to osteoporosis.
“It’s different doing research here than it is a lot of other places,” Hayes said. “It’s very applied. It has to be relevant to what the agency’s needs are. You also have to learn to translate what you learn clinically or scientifically into engineering terms so that engineers can build the equipment or the monitors or the hardware that you need.”
So what’s next?
Hayes says it’s likely there will be more one-year missions in preparation for the big one: the three-year mission to Mars. As the scientists keep an eye on commercial space flight, which is now ferrying supplies to the International Space Station, they’re still thinking about exercise. And their questions this time around span the range of how to protect the astronauts from radiation, how they’ll adapt to Mars’ gravity, and how to keep them fed and healthy in body and mind.
And what will they do when astronauts are more than a few seconds’ delay on email or phone away on Mars? They’ll continue to develop manuals and training that have seen astronauts from the Space Shuttle days to Scott Kelly make it through. And then they’ll trust the crew.
“One of the things we’re looking at now is the need for autonomy because we’re here,” Hayes said. “We have a whole team of physicians and trainers and scientists and engineers here to help them in any way they'll need support when they come home, but when they get to Mars, and they have to recover on their own, they are really on their own.”
Read more on how she ended up at NASA:
I was a girl from a very small town in New Jersey and really didn’t have my sights set on working at NASA. I really believe that if you think big enough anybody can do this and do much bigger things than those that have come before them. The lessons are not to set limits for yourself because I think five or 10 or 30 years after college you really might be surprised in how far you’ve gone.
The opportunities are limitless. This University gave me such a great foundation for being able to tackle just about anything. I’ve stepped into things I never thought I’d be doing. I’m certain there are other folks out there that feel the same. I’m just lucky to have had the opportunities I had at WVU. It really is a great place to learn.
On her first job at NASA flying on the ‘Vomit Comet:’
A big part of my first job was to fly and test equipment and perform research on the KC-135 zero-gravity aircraft that was also called the “Vomit Comet.” The initial experiments studied what makes astronauts experience motion sickness in space. About 60 percent of them get motion sickness symptoms. About 30 or 40 percent actually vomit when they first arrive in space.
Our laboratory was trying to figure out how to predict what kinds of people were more likely to get sick versus others. So we administered a battery of tests on the ground with the final test assessing motion sickness symptoms on those test subjects on the KC-135. We established a normative database to find predictors of space motion sickness. In the end we found none of our ground tests could forecast [motion sickness] among astronauts in space.
On how she developed the exercise program used on the International Space Station:
Our team performed quite a few experiments on the shuttle. You find the body starts to adapt very quickly to the environment in space.
For example, with skeletal muscle loss, you start seeing change at the muscle-fiber level even after five days of spaceflight. We also measured performance changes over two-week shuttle missions. However, in just about everything, there’s lots of individual variability. The evidence showed we would need a strategy to protect the anti-gravity muscles, also known as the postural muscles – the muscles in the legs, abdomen and back – because this is where we saw the greatest losses.
While we didn’t see much loss in aerobic capacity or anaerobic capacity in Space Shuttle astronauts, we hypothesized that a six-month mission would result in changes in aerobic performance if crew members did not exercise aerobically.
Not only did we perform human performance experiments on the Space Shuttle, we also conducted studies using test subjects in a bed-rest model. NASA uses an analog environment to spaceflight – called six degrees, head-down bed rest – for humans to mimic the physiological effects of spaceflight. These analog studies allowed NASA to assess human physiology and performance over weeks and months of inactivity to help anticipate what might be experienced over months on a space station.
Then, in the 1990s, the agency partnered with the Russian space agency to put American astronauts on their Mir space station. This offered NASA the opportunity to live and work with Russian cosmonauts on Mir for several months and expanded our evidence base with U.S. astronauts on longer stays in space, up to 5 months in duration.
In the process, we defined the need for a treadmill, a cycle ergometer, and a resistance exercise device for the International Space Station. A large part of my career was defining the requirements for the ISS exercise countermeasures. Now, astronauts are allotted two and a half hours a day for exercise in-flight using a treadmill, cycle and the advanced resistance exercise device.
On how she sees her job:
Primarily, my job – and that of the teams I work with – is to preserve astronaut health and performance on human space missions for exploration. However, sometimes the work we do can actually be spun off into terrestrial medicine to help other people, whether it be through rural medicine or remote medicine or telemedicine. As one example, the studies NASA sponsors in understanding bone loss in space might help those on Earth diagnosed with osteoporosis.
On the Space Shuttle program:
The Space Shuttle was an amazing vehicle. It was capable of sending six or seven people into space to perform science or space walks. Of course we had to have the Space Shuttle to launch and build the International Space Station.
We learned quite a bit using the Shuttle as a platform to test equipment and procedures. We’d assess whether a piece of hardware could function in space – an air quality monitor or a radiation monitor or a cycle ergometer. We could test these systems quickly on the Space Shuttle and discern whether or not that was going to be something that we could live with long-term for the ISS. It also gave us a glimpse at what might happen physiologically to the crew member, at least it helped us characterize what the first two weeks would look like, which is where much of the physiological change happens. Changes happen quickly, and then taper off a little more gradually over months.
On life at NASA after the Space Shuttle retired:
It’s a different time now. I started my career early in the Space Shuttle program followed by opportunities to work with the Russians on the Mir program and now supporting the ISS.
When the shuttle retired, it was a dramatic change in the way NASA does business. Right now we rely on our Russian partners to launch U.S. astronauts into space. We’ve been doing that, of course, since the shuttle retired for a few years now.
There is some excitement because the United States is shifting towards encouraging commercial space flight. Their recent successes have been really thrilling for us to see at NASA. Commercial space companies have been able to launch and dock to the space station with cargo payloads (with equipment, food and water).
What really gets challenging is when they start launching humans on those commercial rockets. You’ll see that within the next five years. That will be a big change. While NASA personnel are currently a little melancholy due to a lack of U.S. capability to launch humans into space to ISS, there will be lots of excitement about having commercial space companies succeed in doing so soon.