Last summer, Bob Bryan underwent a hip resurfacing surgery

Twenty-four years after first making their debut on the world stage at the 1995 U.S. Open, Mike and Bob Bryan are back in Queens — and playing together at the Grand Slam tournament once again.

“We played first in ’95 when we were 17 years old, so we’ve seen this place change, evolve,” Mike tells PEOPLE of his storied tennis doubles career alongside his twin brother. “The Arthur Ashe stadium wasn’t even here. Now, 25 years later, we’re 41, kind of just walking in here, soaking it all up. Because we don’t know how many opens we’re gonna play.”

The siblings, 41, have the most doubles titles ever in the open era, and have won 5 U.S. Open men’s doubles titles together. But last year, their longtime partnership was forced to take a year off, as Bob underwent hip-resurfacing surgery in August 2018.

“The pain was excruciating,” Bob says. “I told Mike, ‘I just can’t, I can’t walk. I can’t put weight on it.’ I was in a wheelchair and crutches. I tried rehab for three months. Mike flew to Florida to try to help me with it, and nothing was working. And yeah, there were definitely times that I thought, ‘Wow, I don’t know if I’ll walk normal again.’ Much less play tennis. I just conceded to go in and go under the knife and get a hip replacement.”

Bob and Mike Bryan
Credit: Julian Finney/Getty

Bob says that the surgery was a big risk, explaining, “A lot of doctors and people thought that, when you get that surgery, you can’t come back to professional sports.”

He adds, “And no one’s ever done it in tennis.”

Bob and Mike Bryan
Credit: Gary M Prior/Allsport/Getty

While Mike hit the circuit with Jack Sock — and won last year’s U.S. Open title, among others — Bob focused on recovery. And recover he did, besting the timeframe he was given and hitting the court just five months later.

He “just wanted to play a match,” Bob tells PEOPLE. Earlier this month, the siblings hit 1,100 tour-level doubles wins as a team.

“We’re really excited to be playing together again. Especially after [Bob’s surgery], I mean, he had a cane,” Mike says ahead of their first match on Thursday. “He couldn’t barely even walk last year at this time. And now we’re back on the court and one of the favorites. So we’re pretty excited.”

Aging, the duo admits, has been an added challenge.

“It’s not getting easier, especially when you get older,” says Mike. “You have to take care of your bodies all day. You have to have the right diet, to take the right supplements. You have trainers helping you.”

Adds Mike, “We’ve spanned a lot of generations. We’ve played against like [Andre] Agassi and [Borris] Becker, and all these guys and now we’re playing against guys half our age.”

Thats why the athletes have turned to products from brand Bulletproof — founded by Dave Asprey and perhaps known best for its coffee — with who they’ve partnered. Bulletproof also offers MCT oils, supplements, proteins and prebiotics, Bulletproof’s biohacking products help the Bryan brothers recover, better and faster.

Says Bob, “We’re spending a lot more time on recovery now. … We know what works for our bodies now.”

Like most siblings, the brothers — who spend 45 weeks out of the year on the road together — have their “good days and we have our bad days.”

Communication, Bob says, is “everything.” He explains, “We have the ultimate communication being twins.”

“I think a good day, it keeps us going as we have an unbreakable bond,” Mike says, adding, “It’s much more satisfying to win with this guy, my best friend — been with him since day one.”