Andy Toth
In calisthenics, there is a legendary "plateau." You master the pull-up, you conquer the dip, and suddenly you find yourself doing sets of fifty reps just to feel a burn. For decades, the solution was awkward and often counter-productive: stuffing sandbags into vests that leaked, using iron-block vests that bruised the ribs, or dangling heavy plates from thin dip belts that dug into the hips and threw off your center of gravity.
Enter Kensui Fitness.
Founded by Remy Mock - a man with two MIT engineering degrees and the analytical background of a competitive swimmer - Kensui has quickly become the "engineering firm" of the calisthenics world. I recently sat down with Remy to discuss how he’s dismantling the traditional limitations of bodyweight training through physics, high-grade materials, and a surprisingly deep philosophical foundation.
The Digital Nomad’s Dilemma: Innovation Born of Travel
Like many of the most impactful innovations in fitness, Kensui started out of necessity. Remy wasn't looking to disrupt a multi-million dollar industry; he was just a digital nomad trying to maintain his strength and performance while traveling across different continents.
"I was travelling as a digital nomad, using my dip belt for weighted calisthenics when I had access to the gym and using gymnastics rings when I didn’t," Remy tells me. "As I used the dip belt which uses plates, I was thinking it would be nice to have a vest that does the same. That’s how I decided to make the EZ-VEST."
The problem with travel-ready gear at the time was either excessive bulk or poor design. Traditional gymnastics rings were a "no-brainer" for training, but they were often cumbersome to pack. Similarly, TRX-style trainers lacked the stability of dual anchors. "I figured they were bulky and I wanted a slimmer device that did the same. Something like the TRX but that had dual anchors. That was the inspiration for the Nanobars," he explains.
This frustration with the status quo - sandbags that leaked, velcro that failed, and equipment that simply wasn't designed for the human frame - led Remy to apply his MIT training to the problem. He taught himself CAD modeling and used rapid 3-D printing to iterate on hundreds of designs. What started as a personal project for a better workout quickly gained traction as fellow athletes at the gym began asking where they could buy his custom gear. "Luckily, when you love what you do, you don't need motivation," Remy notes. "I'm fortunate that I love what I do."
The "Bushido" Philosophy: Integrity Over Gimmicks
The name Kensui (Japanese for "pull-ups") pays homage to Remy’s Japanese heritage, but the brand’s soul is rooted in the Bushido code - the warrior’s way of life. For Kensui, this isn't just marketing; it’s an operational framework based on diligence, integrity, and gratitude.
"We only sell and manufacture fitness products that we use ourselves and truly believe are beneficial," Remy explains. Unlike brands that rely on "fitness model" gimmicks or re-labeling generic factory gear, Kensui focuses on the actual science of the load. "I’m the most proud of my designs that are simple and elegant. I would say the DUO-rings are the epitome of that and although not a bestseller I am proud of that design. I’m also quite proud of the Swissies as it’s another example of a very simple design."
This commitment to integrity extends to their social impact. Kensui isn't just about building muscle; it’s about building a better world. In December 2019, just two weeks after launch, they began donating a portion of their profits to causes like clean water initiatives and veteran support. This sense of "Gratitude" is a core pillar that distinguishes them from the crowded landscape of fitness startups.
Product Innovation: Breaking the Bodyweight Ceiling
When I asked Remy what the "must-haves" were for a serious calisthenics athlete or someone building a home gym, he highlighted four specific tools designed to solve the most common training bottlenecks.
1. The Kensui DUO-Rings: Redefining the Standard
"DUO-rings are just a no-brainer because all gymnastic rings are a no-brainer for calisthenics," Remy notes. "You can essentially train every body part with infinite variations with them. They are also light weight, portable and can be used anywhere - even with a door using a door anchor."
However, he saw a flaw in the "standard" ring. Traditionally, you had to choose between 28mm (FIG standard) or 32mm (power/crossfit standard) thickness. "What sets the DUO-Ring apart is that it offers a dual thickness design so you don’t need to settle for just one thickness. Both the 28 and 32mm have their place." This allows athletes to train grip strength and specific movements without owning two sets of equipment.
2. Kensui YinYangs: The Evolution of the Parallette
For floor movements like handstands and planches, Remy developed the Yinyangs. "Handstands and planche can cause injuries if not trained carefully and it’s recommended to alternate between using the floor and parallettes depending on how your wrists and joints feel at the time of training," he advises.
The Yinyangs feature a patent-pending interlocking design that makes them incredibly portable, held together neatly by internal magnets. But the real "nerd" detail is in the grip. "We used the handle cross section that mimics the FIG standard gymnastic pommel horse handles," providing a professional, ergonomic feel that traditional round pipes simply can't match. "Yinyangs are a great addition to train floor movements while preventing joint strain from overuse."
3. Kensui Swissies: The Neutral Grip Revolution
One of the most innovative additions to the Kensui lineup is the Swissies. These neutral-grip bar attachments are designed to solve the universal problem of joint pain and limited engagement during heavy pulls.
"I’m quite proud of the Swissies as it’s another example of a very simple design," Remy says. For the calisthenics athlete, a straight pull-up bar can be restrictive. It forces the wrists and elbows into a fixed plane that doesn't always align with natural human anatomy. Swissies allow the user to instantly convert any standard bar into a multi-grip station.
Beyond just comfort, they offer a significant performance boost. By allowing for a neutral grip (palms facing each other), Swissies improve "irradiation" - the phenomenon where a stronger grip leads to greater muscle recruitment throughout the arm and back. The Swissies MAX version even includes specialized "fin-shaped" palm supports to further enhance this effect. However, Remy warns against common user errors: "Many people mix up the left and right handles on the Swissies MAX so the fin-shaped palm supports are not being used properly." When aligned correctly, these tools are a "cheat code" for back development and elbow longevity.
4. The Kensui EZ-VEST: Physics vs. Friction
The flagship of the Kensui line is undoubtedly the EZ-VEST. As a calisthenics founder myself, I had to ask the tough question: My first thought was, 'Why not just use a dip belt?' From a design and biomechanics standpoint, what problem does a plate-loaded vest solve that a dip belt simply can’t?
Remy’s answer was a lesson in biomechanics. "The dip belt is a perfectly good solution for certain exercises like the pull-up, muscle-ups and the dip. However, it’s not ideal for other movements," he explains. "The vest can be used for rucks, push-ups, rows, jumping lunges, squats, good mornings, ab-rollouts and many more."
Crucially, the EZ-VEST handles weight differently than a traditional vest. "A 100lb standard vest [using sand or iron blocks] is much harder to use than a 100lb EZ-VEST. Because the EZ-Vest uses weight plates, it gives you a very rigid place to grab it. It’s hard to explain in words just how lifting a 100lb soft sandbag is much harder than a 100lb rigid barbell, a 100lb standard vest is much harder to use than an EZ-VEST." This rigidity ensures the weight stays close to the body’s center of mass, preventing the "pendulum effect" that often leads to lower back strain.
Mastering the Progression: Joint Health and Sustainability
One concern for our readers at Calisthenics.com is always the risk of injury. Adding weight too aggressively can wreck elbows and shoulders. Remy, having transitioned from an elite swimmer to a digital nomad and business owner, understands the long game.
"As I get older I definitely understand the importance of progressing slowly and carefully," he tells me. One concern athletes have is that adding weight too early can lead to elbow and shoulder issues. To combat this, Kensui emphasizes scalability.
"We offer many items such as bands, micro plates and plate loaded gear to help with progressions. And our various grips help to increase exercise variations for good joint health and preventing overdoing a single variation, as this can cause issues both in terms of injuries and training plateaus."
Performance-Driven Materials: Beyond Steel
Another "hidden" detail of Kensui is their choice of materials. While many brands default to heavy steel, Remy argues that it isn't always the best choice for the athlete.
"We like to cater to everyone regardless of their financial situation. We often make things out of nylon, aluminum or wood that other companies make with steel," Remy says. "We believe steel is overkill for many items. Often it's not even the ideal material for most applications as it’s very heavy, and prone to rust. We try to make everything as durable and practical as possible, but we don’t like to think of ourselves as 'premium' in an elitist sense."
There is also a practical, sensory reason for these choices. "We love nylon and wood material as many calisthenics athletes train outside and touching a steel handle in the cold is no fun." By using ballistic nylon (the strongest fabric in existence) and aircraft-grade aluminum, they create gear that is durable enough to hold 300+ lbs while remaining light and comfortable for year-round training.
How Kensui Ensures Global Shipping
Operating out of warehouses in the USA, Canada, Europe, and China makes Kensui a truly global brand. Remy is actively working to make high-level gear accessible to everyone. "We have multiple warehouses... which help us to ship to smaller countries much faster and cheaper than if we only shipped from the US, like most other companies."
He is constantly listening to feedback to improve the customer experience. "We want to expand to have a UK and Australian warehouse as we have a lot of customers there and want them to get their products more seamlessly." This global outlook reflects his background as a digital nomad who knows the frustration of international logistics firsthand.
The Role of Calisthenics Equipment in Bodyweight Training
As we wrapped up, I asked Remy how he sees the role of equipment evolving as calisthenics continues to grow. For him, equipment isn't about replacing the body’s work, but rather about making that work more effective.
"Ever since Covid there has been a renaissance period of new fitness equipment, including those for calisthenics and I believe it will continue," he says. While he keeps his cards close to his chest regarding future designs, he did hint at one area of focus: "I can’t get into too much detail but there’s a few issues with resistance bands that I think can be improved."
Final Thoughts from Calisthenics.com
The takeaway for our readers is clear: Calisthenics is no longer just about moving your own body. It is about mastering movement through intelligent progression. Whether you are using the Swissies to save your elbows or the EZ-VEST to break through a strength plateau, the key is to use tools designed by people who actually do the work.
Remy Mock’s journey from a frustrated athlete with a leaky sandbag vest to an MIT-trained innovator has provided the calisthenics community with something rare: equipment that respects the physics of the human body. As the discipline continues to evolve, Kensui is setting the standard for what "gym gear" should be: simple, elegant, and uncompromisingly effective.
You can explore the full Kensui line and the innovative EZ-VEST at KensuiFitness.com. Follow Remy's design journey on Instagram @KensuiFitness and join the community of "strength nerds" pushing the boundaries of what is possible with bodyweight training.
