If you can reduce exercise time, it frees up more time for science and breakthroughs.
As humanity prepares to return to the moon and venture deeper into the cosmos, a quiet but consequential challenge persists: the human body was shaped by gravity, and in its absence, it begins to unmake itself. Engineers, athletes, and space agencies are now converging on a new generation of exercise devices — compact, efficient, and purpose-built for microgravity — that could reduce the daily physical toll on astronauts from two hours to thirty minutes, freeing them to do the work that space exploration is ultimately for.
- Without gravity's constant resistance, astronauts lose muscle and bone density within days — a biological clock that ticks against every long-duration mission.
- Current space station exercise machines demand two hours of daily use, consuming precious time and offering limited versatility aboard already crowded spacecraft.
- British inventor John Kennett's HIFIm device — built by Oscar-winning special effects engineers and tested in real weightlessness aboard parabolic flights — promises 300 exercises, zero electrical power, and a 30-minute daily routine.
- NASA, ESA, the Canadian Space Agency, and the UK Space Agency are all evaluating competing designs, with the Artemis lunar program and future deep-space missions as the ultimate proving ground.
- If the efficiency gains hold, astronauts could reclaim 90 minutes a day for science and exploration — a shift that could fundamentally change what long-duration missions are able to accomplish.
On a plane climbing and plunging through the sky, Olympic rower Matthew Wells straps into a rowing machine and pulls with everything he has. For 22 seconds, gravity disappears. He is testing equipment that may one day live on the moon.
The problem Wells is helping to solve is deceptively simple: in space, there is nothing to push against. On Earth, muscles and bones are constantly loaded by the work of moving through gravity. Remove that force, and the body begins to deteriorate within days — muscle mass, bone density, coordination, all of it. For decades, the answer has been brute endurance: astronauts aboard the International Space Station spend roughly two hours every day exercising on machines that are heavy, power-hungry, and limited in scope.
John Kennett, a former aircraft engineer and pilates studio owner, believes he has a better way. His device, HIFIm — High-Frequency Impulse for Microgravity — is compact, requires no electrical power, isolates vibrations to protect sensitive experiments, and delivers 300 different exercises. The idea came to him while working with a cancer survivor experiencing severe bone loss. He saw the parallel with astronauts immediately. HIFIm was built at Pinewood Studios by the special effects team behind 1917, Star Wars, and James Bond — but craftsmanship alone couldn't test it. Only real weightlessness could, which is why Wells ended up on a parabolic flight arranged by the European Space Agency.
HIFIm is not the only contender. The European Enhanced Exploration Exercise Device, developed by the Danish Aerospace Company for ESA, combines resistive training, cycling, rowing, and rope-pulling with motion capture technology. Multiple teams worldwide are racing toward the same goal, with Artemis lunar missions, the Gateway orbital station, and future deep-space exploration as the prize.
Dr. Meganne Christian of the UK Space Agency calls this a genuinely exciting moment. If Kennett's projections are correct and astronauts can stay fit in 30 minutes rather than two hours, the time reclaimed could be devoted to the science and discovery that justify these missions in the first place. For Wells, the parabolic flight was the most physically outrageous challenge since his Olympic career — and a chance to contribute to something that might one day help humans live beyond Earth. The race to determine which design earns a place on those missions is already underway.
On a plane climbing and diving through the sky, Olympic rower Matthew Wells straps into a rowing machine and pulls as hard as he can. For 22 seconds, his body floats. There is no water beneath him, no boat, no gravity—just the sensation of weightlessness 28,000 feet above the ground. He is testing a piece of equipment that may one day live on the moon.
Wells is one of several athletes and engineers helping space agencies solve a problem that sounds simple but isn't: how do you keep astronauts fit when there is no gravity to work against? On Earth, our muscles and bones are constantly engaged in the work of moving against weight. In space, that stimulus vanishes almost immediately. Astronauts lose muscle mass and bone density within days. Their coordination suffers. Their ability to perform the physical tasks their missions demand deteriorates. The solution, for decades, has been brute force—astronauts on the International Space Station spend roughly two hours every single day exercising, using current machines that are heavy, time-consuming, and limited in what they can do.
A British inventor named John Kennett thinks he can change that. His device, called HIFIm—High-Frequency Impulse for Microgravity—is compact enough to fit in a spacecraft yet capable of delivering 300 different exercises. It requires no electrical power. It isolates vibrations so it won't interfere with delicate experiments or the structural integrity of a vessel. Kennett, a former aircraft engineer who also owns a pilates studio, came up with the concept while working with a cancer survivor struggling with severe bone loss. He realized the International Space Station was, as he puts it, missing a trick. If the same physics that threatens astronauts' bodies could be addressed with the right equipment, missions could be transformed.
The device was built at Pinewood Studios by the same special effects engineers who won an Oscar for the film 1917 and who work on Star Wars, James Bond, and Mission Impossible. But no amount of craftsmanship on Earth could fully test it. Rowing in particular cannot be properly evaluated without actual weightlessness. That is why Wells found himself on a parabolic flight—a plane that climbs steeply and then dives, creating 22 seconds of microgravity before the maneuver repeats. The European Space Agency arranged the tests. NASA, the Canadian Space Agency, and the UK Space Agency have all been involved in developing and evaluating the equipment.
HIFIm is not alone in this race. The European Enhanced Exploration Exercise Device, or E4D, developed by the Danish Aerospace Company and commissioned by ESA, offers four modes—resistive training, cycling, rowing, and rope pulling—along with motion capture technology to track performance. Other teams around the world are working on competing designs. The stakes are real. These devices are being built for the next generation of long-duration space missions: the Artemis program, which aims to return humans to the lunar surface and establish a permanent presence there; the Gateway Space Station, an orbital outpost that will support lunar operations; and future deep-space exploration.
Dr. Meganne Christian, a reserve astronaut for ESA and Senior Exploration Manager at the UK Space Agency, describes this as a genuinely exciting moment in space exploration. Gateway may have been sidelined by NASA's shifting priorities, but the equipment being developed for it can be deployed on new space stations and on the lunar surface itself. The efficiency gains matter enormously. If Kennett's team is right, and astronauts can maintain fitness in 30 minutes a day instead of two hours, that frees up time for the actual work of exploration—the science, the experiments, the discoveries that justify the missions in the first place.
Dr. Dan Cleather, a professor of strength and conditioning at St. Mary's University who designed the monitoring technology for HIFIm, explains the physics plainly: in space, muscles and bones immediately begin to deteriorate because they are not being loaded by gravitational forces. The solution is not just exercise, but the right kind of exercise, delivered efficiently, without the bulk and power requirements of current machines. Wells, reflecting on his experience in weightlessness, calls it the most outrageous physical challenge he has undertaken since his Olympic days. For him, it is a chance to contribute to something that might one day help humans live and work beyond Earth. For the space agencies backing these projects, it is a necessary step toward making long-duration space exploration sustainable. The race is on to see which design will earn a place on the missions that take us back to the moon—and beyond.
Notable Quotes
In space we don't experience any forces, our muscles, our bones immediately start to diminish because we're not being loaded by those forces.— Dr. Dan Cleather, professor of strength and conditioning at St. Mary's University
If you can reduce the amount of time you're exercising, it frees up more time for astronauts to do science and experiments which could cause a whole range of breakthroughs.— Dr. Meganne Christian, UK Space Agency
The Hearth Conversation Another angle on the story
Why does this matter so much? Astronauts can just exercise more efficiently, can't they?
The problem is time itself. Two hours a day in space is two hours not doing science, not conducting experiments, not exploring. If you cut that in half, you've fundamentally changed what a mission can accomplish.
But couldn't they just accept being less fit for a few weeks?
Not really. Bone density loss starts immediately. After a few weeks, astronauts lose the physical capability to do their jobs—to repair equipment, to move through a spacecraft, to handle emergencies. It's not optional.
So this is about making space missions actually feasible for longer periods?
Exactly. Without solving the fitness problem, you can't sustain a lunar base or send people to Mars. The equipment is the infrastructure that makes deep space exploration possible.
Why is a rower testing this in a plane instead of just simulating it on Earth?
Because rowing requires you to push against resistance while your body moves through space. You can't replicate that on Earth—gravity always pulls you down. You need actual weightlessness to know if the machine works.
And if this device works, what changes?
Astronauts get their time back. Science gets prioritized. Missions become longer, more ambitious. It sounds small, but it's the difference between visiting the moon and actually living there.