It’s off the beaten path now, amidst warehouses and abandoned railroad tracks a block away from Mandela Parkway, where the busy doubledecker I-880 Cypress Structure once carved through West Oakland before it collapsed in the Loma Prieta earthquake three decades ago.

The DeFremery Swimming Pool, built in the Depression era, was here long before that freeway came and went. Its dark lobby, the faded lane markers on its walls and its 33-yard length —modern American lap pools are built at either 25 yards (short course) or 50 meters (long course) — make DeFremery somewhat of an Oakland relic.

But the antiquated pool is still very operational. In fact, it’s the little-known home of some of the most innovative training in sports, as several NFL players can attest. Invented in these waters, the Aquabred strength-and-conditioning program could represent the wave of the future when it comes to injury prevention.

“These guys are truly thinking outside the box,” said Kentavius Street, the 49ers defensive lineman who tore his ACL in 2018 and has spent the past several months supplementing his rehabilitation routine with underwater work. “They’re always pushing for something new. … Introducing your body to new movements in the water benefits everything you’re doing —new muscles, new joints. It’s something that working outside can’t produce.”

Eight NFL players have added Aquabred to their training regimens over the past year. That includes six Raiders (running back Jalen Richard, punter Johnny Townsend, running back DeAndré Washington, defensive linemen Arden Key and Johnathan Hankins, and safety Karl Joseph), the 49ers’ Street, and Los Angeles Rams cornerback Marcus Peters (an Oakland native).

On a sunny Friday afternoon in early June, Richard and Townsend dove in. So did the hulking Street —with a big splash, of course. Brandon James, a former Diablo Valley College swimmer who holds the national JC record in the 200-yard backstroke, and Egyptian swimmer Abdallah Mahgoub, who also swam for DVC and is gunning to compete in the 2020 Tokyo Olympics, joined the NFL trio in the water.

“Everyone in this pool right now is elite,” Piankhi Gibson, the 26-year-old founder of the Aquabred, said as he eyed the group from the deck.

The group was not here to swim laps. Envision standard gym equipment —free weights, treadmills, medicine balls, even bench presses and squat racks —all submerged underwater. An athlete’s immersion here, Aquabred asserts, creates an environment that’s simultaneously suited for recovery and the types of strengthening that’ve been historically neglected by land sports. Gibson, a self-described autodidact, describes Aquabred as a “specific gravity training system” that strives to fully capitalize on water’s distinctive properties.

The program is still in its infancy, not part of any NFL team’s curriculum. But those involved believe that it’ll become a fixture on the sports training scene.

“And this shit works,” Richard said recently at the Raiders facility, noting that he felt less winded and healthier during the 2018 season, the most productive of his career, after Aquabred training. “It builds your lungs. It takes pressure off the body, relieving your body from gravity. It does what everybody says pool workouts do, but (Gibson) is taking it to a different level with the things we are able to do in the water.”

Given the devastating impact that injuries have had on multiple Bay Area sports franchises as of late, examining a tool that can potentially keep athletes healthier may be more relevant now than ever. The Warriors, of course, saw their recent NBA title bid derailed by injuries to superstars Kevin Durant and Klay Thompson, while last season’s 49ers put more money on injured reserve than any team in NFL history.

A central medical pillar is the basis of Aquabred’s potential in injury reduction, and it lies in the body’s all-enveloping fascial network, a sheet of connective tissue beneath the skin that attaches, stabilizes and separates muscles and other internal organs. The importance of this organ system — detailed further below —has exploded within the medical community in recent years, and Gibson is convinced that Aquabred holds an avantgarde key in targeting the fascia to build more durable athletes.

“We’re reaching out to the Raiders as a team now, and after that, maybe the entire NFL,” said 25-year-old Dylan Stine, Gibson’s right-hand man at Aquabred. “This is something we eventually want to get into the ecosystem of these owners. Most pro sports teams have aquatic space, but they’re not utilizing the pool time outside of rehab.”

Gibson swam at Auburn University and started developing Aquabred in 2013. He met Stine growing up in Oakland. The two raced as youths in the city’s recreational league at DeFremery, stayed in touch over the years and eventually combined forces in this business venture.

So on this particular Friday, they were again back in a familiar place.

I hopped into DeFremery Pool, too, getting a fully submerged tour of the Aquabred program. I got to see NFL players and top swimmers — whose specialties and training focuses had long been on opposite ends of the athletic spectrum — all floating together in the same laboratory. Gibson has created a visually surreal world, one in which an NFL running back sees his training regimen enter the aquatic domain of someone like Brazilian Olympian Bruno Fratus, another Aquabred client.

“Water,” Gibson said of this surprising union, “is the great equalizer.”

Players use snorkels when initially going underwater for bike or treadmill work, which proves to be a particularly novel experience. The Raiders’ Key loves to yell “I’m going under!” before full submersion, Stine notes with a smile.

As a player advances in the program, he can ditch the snorkel and reach breath-holding depth, where water pressure is greater and work on Aquabred’s bevy of instruments becomes more challenging. Some of the workout details, such as reps and set counts, are proprietary, but the founders say that it varies from athlete to athlete, anyway.

“How can we make Kentavius Street’s weaknesses stronger?” Gibson asked as he began outlining Aquabred’s effort to build longer-lasting NFL players. “With these guys at the top of their game, there aren’t many new sensations you can introduce them to. They’ve already tried everything. They’ve already lifted 700 pounds.”

(Street has, in fact, squatted 700 pounds on land, (https://www.youtube.com/watch?v=KHQ8bk4r_k0) and video of his Aquabred work is below.)

“The answer is the water,” Gibson said. “It’s a formula we want to teach strength-and-conditioning coaches. You have a high school swimmer next to an NFL running back, and the NFL running back is struggling to run on the treadmill. It’s a humbling sensation of, ‘wow, I have so much more to learn.’”

Water is 800 times denser than air, but it’s also more physically forgiving, since its buoyancy supports about one-third of equivalent land weight (300 pounds weighs roughly 200 pounds in water, for example). This offers athletes a “flushing” respite from heavy-impact training on land. And, since added pressure buoys circulation, it’s an ideal environment in which to develop breathing efficiency. For football players, whose mouthpieces necessitate breathing through the nose, this comes as an unexpected aerobic bonus.

During his workout, Street is as powerful as one might expect. The lineman launches off the shallow end floor with a squat — it has volcanic effects on the previously tranquil pool — and a heavy medicine ball goes flying at least 15 yards before displacing a good amount of the pool’s water on splashdown. He creates more violent waves when he pushes Gibson’s two custom-made circular plates back and forth against the water, and he powers hard on the submerged bike — sometimes for as long as 15 minutes.

Street is aiming to progress soon to this exercise, which Gibson showcases here (https://www.instagram.com/p/ByEsPKlgVYC/): It involves explosive 235-pound squat presses off the pool floor, all combined with a flutter kick, an underwater movement that’s long been used exclusively by aquatic athletes.

As a former competitive club swimmer and coach, I have an added fascination with Aquabred. I had never expected to come across a place where swim training principles and some of football’s strongest linemen converge. So while Street, Richard and Townsend held their breath riding stationary bikes on the DeFremery Pool floor on that Friday afternoon, I swam to the bottom of the deep end and grabbed the 35-pound kettlebell lying there. It was time to try something new.

Momentary panic followed.

Clutching the kettlebell, I felt as if a magnet had sucked me onto the pool’s floor. The closest breathable oxygen was far above me, nearly 10 feet up, so roughly 18 pounds of water pressure hit every inch of my body and fought to keep me away from air.

It was unnerving, to say the least. Imagine feeling like a fish out of water, but in the water. At moments like this, instinct takes over. So I launched into a squat-based thrust off the pool floor followed by the undulation of dolphin kicks to propel myself upward.

But nothing came easy. The Saturn V rocket built momentum after liftoff. I didn’t. Not with that kettlebell fighting the tug-of-war with all its might. And in these few seconds of underwater struggle, as I kicked hard just to stay suspended in the same place, I appreciated an entirely new sensation —one that combined weightlifting’s demands for power with the immersive properties exclusive to water.

Muscles I didn’t know existed felt activated. “Proprioception,” Gibson explained long after I dropped the kettlebell, shot back up to the water’s surface and sucked in a big breath of fresh air. “It’s your body’s sense of itself in space and movement. When completely covered in water, you have a complete understanding of where you are in space. You take that awareness, you increase the viscosity and resistance, and you engage with your core in a much deeper way.

And the core is the epicenter of your body, especially as you get back on land. You feel more connected, you feel more agile and you can move a lot easier.”

There may be nothing that engages that core —and nothing that highlights the uniqueness of water —more than fighting 35 pounds of dead weight deep under the surface

Gibson believes that within the context of this crossover and adjustment, water carries massive training and healing potential.

He points to a Washington State University study ( https://books.google.it/books?id=ISc_AQAAQBAJ&pg=PT116&lpg=PT116&dq=improve+aerobic+capacity+water+washington+state&source=bl&ots=xeNJqx0zye&sig=ACfU3U2XkIJRCDv-7WzcBDzwkpzuOs4PCw&hl=en&sa=X&redir_esc=y#v=onepage&q=improve%20aerobic%20capacity%20water%20washington%20state&f=false ) which concluded that water workouts are the only path toward drastically improving respiratory endurance. He cites Aquabred’s own tracking of caloric output, which has found that an hour on an underwater bike or treadmill can burn about 500 more calories than the same duration of bike or treadmill work on land.

But most significantly, there’s the fascia, that all-enveloping layer of tissue that had long been discarded as extraneous tissue in the dissection of cadavers. Thanks in large part to the introduction of miniature cameras, which can probe under the skin and examine intricacies on an intercellular level, that’s not the case anymore.

The fascia has come into new focus, and Gibson discusses it with vigor.

“Fascia is this interconnected, hydrodynamic entity in our body that is revolutionizing the medical field,” Gibson said, citing the work of Dr. Robert Schleip and Tom Myers, two leading experts in the study of the fascial network. “They’ve said it’s the equivalent to finding a new element on the periodic table.”

Schleip’s book, “Fascia in Sport and Movement,” is the authoritative work on the subject. Gibson is quick to espouse Schleip’s key findings — especially the fact that fascia plays a flowing role in all functional movement, and that poor fascial hydration, lubrication and preparation are very often involved in injuries.

Perhaps the fascia had sailed under the radar because of how differently it operates — “it’s a living, breathing matrix, a web, innervated through our entire body like an organic internet,” Gibson explained —but these very same properties are the ones that make it so important in the understanding of athletic health.

“If a muscle is strong, just through standard weightlifting, but the fascia isn’t ready, that fascia is just going to shear off,” Gibson said. “When athletes get injured, a lot of the time, it’s because there isn’t that slide and glide in their tendon network. A little awkward fall, it looks like it’s not a big deal, but it’s a snapped Achilles.”

That’s opened the pivotal question here: How can the fascial network be targeted and trained to reduce the risk of injuries?

Myers’ 10 tips for fascial fitness (https://www.yumpu.com/en/document/read/11979111/tom-myers-10-tips-for-fascial-fitness) emphasize the importance of fascial elasticity, hydration and a focus on interconnectivity (as opposed to isolating specific muscles) during workouts.

Trainers of land sports are not ignorant of these principles. The prolific rise of resistance band training in recent years is an adoption of them, for example. But Aquabred firmly believes that a revolutionary next step lies beyond that, in the enveloping environment of water, where proprioception is heightened and more resistance can be added to take aim at the fascial system.

“Once I learned that the fascia was hydrodynamic,” Gibson said, citing this realization as Aquabred’s aha moment,“it only made sense to perform hydrodynamic movements to target the system holistically.

“The best, most efficient way to engage the fascia is to be completely covered in water. How do we target the system as a whole? We think the answer is Aquabred. We think the answer is the water. It’s a different set of rules in the water.”

Time, of course, will be the ultimate judge here. More land athletes must add the system to their training regimens, and more time must elapse to return a significant sampling of data. But the mere possibilities that Aquabred is generating within the NFL and other impact sports are intriguing in their own right, and its earliest clients bubble with praise.

“Your body gets used to a lot of different workouts, so at the very least, it’s good to mix it up,” Richard said. “I’m always down for new shit, new ways of training to make me better, make me healthier. And I’m seeing progress and building my body here.”

Aquabred’s clients include actual swimmers, too. That includes Fratus, who is currently the world’s fastest swimmer.

In an interview via WhatsApp from Europe, where he recently posted the world’s best 50-meter freestyle time of the year (21.31), the Brazilian Olympian explained he understands why football players would want to train like him, and vice versa.

“I like to prepare myself like a football player,” said Fratus, who has his eyes on the swimming world championship this year and an Olympic gold medal in 2020. “Swimmers are known for not being that athletic, but I consider myself a swimmer who is and can throw up weights. The fact that Piankhi has been working with so many NFL players — I can use my preparation to develop the athleticism that football players have.”

Fratus’ adoption of Aquabred underscores that land athletes aren’t the only potential beneficiaries. The crossover gains of porting impact sport training into the pool can work in the opposite direction, too. From a mental perspective, swimmers can break up monotonous and mentally taxing lap training —“they can play swimming,” Gibson says, pointing to Fratus’ reel of underwater work:

It’s worth noting that Fratus, who trains in Florida, does some of his submerged weight training at a depth of 20 feet, far from breathable oxygen —which is possible only because his body has acclimated to intense water pressure.

(Gibson, whose dad is a scuba diver, has rigged pony tanks to stay submerged for 15 minutes while experimenting with deep water exercises.)

Remarkably, when Fratus initially swam the world’s fastest 50-meter freestyle time of the year in April, he did so only seven months after undergoing surgery to fix a partially ruptured tendon in his shoulder.

“That’s unheard of, from the type of injury he had, to come back so quickly,” Fratus’ coach Brett Hawke, a former Australian Olympian who swam alongside Ian Thorpe, said in a phone interview earlier this month. “I think a lot of people are shocked at how quick the turnaround has been.”

Fratus and Hawke credit a wide array of doctors, physiotherapists and trainers for the rapid recovery, with the introduction of Aquabred to the regimen as a piece of that puzzle.

“We were looking at getting strength back as quickly as we could, but we didn’t want to pound in the gym,” Hawke said of Fratus’ training. “The movements we were doing with Piankhi really allowed Bruno to gain the strength we need back in the shoulder joint. It enabled Bruno to connect core to shoulder, which has given him more feel for the water, power in the water.”

Aquabred’s big break came in 2018. The Raiders’ Richard was at Forma Gym in Walnut Creek for a Pilates class. Gibson just so happened to be instructing an aqua cycling class there at the same time. The water work piqued Richard’s interest, and he signed on to become Aquabred’s first NFL client.

Gibson tailored the running back’s program for football performance. He even used a friend’s 3-D printer to make two footlong cylinders, featured in Street’s training video above, that serve as underwater versions of battle ropes.

“What stands out to me is his creativity,” Richard said of Gibson. “He builds all his own shit, came up with it, wrote the models. That’s fire. Not a lot of people are able to do that.”

Once Richard took to social media with his new underwater training, other Raiders and the 49ers’ Street noticed and hopped aboard, too. The word has spread even further since, as pro athletes aren’t Aquabred’s only higher-profile clients.

Gibson also works with Berkeley resident Arash Bayatmakou, who broke his neck during a fall from a third story balcony seven years ago, an injury that paralyzed him from the chest down. Bayatmakou, who can now stand and is working toward the goal of walking again, has delivered TEDx talks and wrote the book “Little Big Steps: A Life-Changing Injury and the Inspirational Journey to Overcome the Odds.”

For Bayatmakou, the potential of Aquabred is rooted in the venture’s open-minded ethos.

“I’ve worked with a lot of different people, amazing physical therapists, kinesiologists, because my injury is a mysterious kind of thing,” Bayatmakou said in a phone interview. “Most of the medical world said I’m not going to get better. You have doctors and physical therapists of 25 years who don’t have the open mind Piankhi embodies.”

It’s this willingness to embrace new ideas that’s turned Aquabred into what it is now: a fledgling player on the pro sports training scene, but one that has the potential to become a game-changer.

Gibson plans for the company to have its own facility by the end of 2020, where it can debut a line of underwater equipment that doesn’t rust in the water (weights must currently be removed from the pool and dried off after each usage). Every additional happy and healthy client will lend Aquabred more credibility in its quest to formally associate with pro franchises.

“We’re just scratching the surface on what we can do in the water,” Gibson said. “This is just the beginning. In 5-10 years, we hope to have hundreds of clients, and a ton of data showing how this work can make careers healthier, longer and more sustainable.”

And if that does indeed come to fruition, this will be a big wave in the sporting world —one that started with a splash into the DeFremery Pool. — Reported from Oakland

(Top photo of, from left, Kentavius Street, Jalen Richard and Johnny Townsend courtesy of Dylan Stine)