Saturday marked the 50th anniversary of the Apollo 11 Moon Landing. The spacecraft's "Apollo Guidance Computer," which controlled and navigated the vessel, had fewer bits of memory or RAM (random-access memory) than the modern-day smartphone. The Apollo 11's Command Module, "Columbia," the living quarters for the three-person crew (Neil Armstrong, Edwin "Buzz" Aldrin and Michael Collins) during most of the first manned lunar landing mission in July 1969, was only 10 feet, 7 inches by 12 feet, 10 inches. Those dimensions didn't exactly allow for jumping jacks or other full-body workouts while in orbit.
Although the technology has since improved, maintaining the fitness and health of astronauts in space still proves to be a challenge.
When astronauts arrive at NASA's center for human spaceflight, the Johnson Space Center in Houston, they are required to physically train for about two years prior to their mission date. "Strength training is the most important way that our crew members prepare their bodies for space flight," said Staci Latham, astronaut strength, conditioning and rehabilitation (ASCR) specialist at the NASA Johnson Space Center.
"Cardiovascular interval training is prescribed preflight to prepare them for the types of workouts they will do onboard. This means things like running, biking, rowing and circuit training."
The first woman commander of the International Space Station (ISS), Peggy A. Whitson, Ph.D. -- who holds the U.S. record for most days in space, placing eighth on the all-time space endurance list -- agrees.
"Fitness is important for the job. Being able to perform spacewalks [when astronauts work outside the spacecraft while in space] is physically challenging," said Whitson, who retired from NASA in 2018. "While the underwater training in the pressurized suit helps with the specifics of what will be performed during the spacewalk, that would not be enough to keep us in condition for that event on orbit."
A treadmill, a stationary bike and an advanced resistive exercise device (ARED), a weight training tool, are frequently used for in-orbit workouts on the ISS. Although treadmills and stationary bikes are typical for earthly workouts, using them in space is quite different. For example, to run on the treadmill, an astronaut needs to put on a previously-fitted harness and chain themselves to the machine to imitate the gravitation pull found on Earth. As for the bike, think of a stationary bike but without handlebars or a seat -- just the pedals.
Although much of the pre-mission physical training is cardiovascular conditioning-based, Latham and the ASCR group encourage crews to participate in other forms of exercise. "[We want our] crew to be well-rounded in their physical preparedness," Latham said. "This includes, but is not limited to, activities like yoga and rock climbing."
Latham also notes that strength training has been most helpful in mitigating the effects of a microgravity environment on the human body, which could impact bone density.
According to NASA, dehydrated foods and drinks make up much of the in-orbit menu. The primary reason for using dehydrated items is that water, a byproduct of the shuttle's fuel cells, is abundantly available for food preparation. Using rehydratable sustenance reduces the weight of the spacecraft.
Before blasting off, astronauts visit the NASA food lab to taste and select their preferences from a menu of 200-plus dishes scientists have developed. The astronauts need to be thoughtful when choosing, as there is no adjusting selection while in space. When it comes time to eat while in orbit, the package for each food item has preparation instructions, including the exact amount of water needed to hydrate it.
Whitson notes that the dish she most loved during her 665 days "up there" was the chicken fajitas. The rehydrated shrimp cocktail was a crew favorite.
"We tried to get creative and do some special things," Whitson said. "For instance, in my bonus food container, I sent up some tubes of icing. And for Christmas, we had a cookie decorating contest.
"I would also try to make up special items for the group. I'd take the same old stuff and try to make it new by combining it differently. [Things like] spiced apples in a tortilla with caramels, melted in our convection oven for space apple pie."
Even so, she missed the ability to create a meal from scratch.
"[I missed] sautéing the onions or the garlic, putting together whatever I imagined," Whitson said. "I didn't have the selection of stuff with which I could get creative."
There is also the matter of watching the sodium level in prepackaged food.
"On my most recent mission, we had an app that helped us count calories," Whitson said. "It was fantastic. It also monitored sodium -- too much sodium is bad for your bones -- and hydration status."
When Whitson returned to Earth from her missions, she'd typically opt for a fresh (read: not dehydrated) steak and Caesar salad. While in space, she often had "a mean craving for a salad" or a piping-hot pizza.
Once the missions were accomplished, it was the simple things that Whitson longed for.