Fight Interviews

Flex-mitt Creator Matt Nussbaum Talks Revolutionizing Boxing Training and Empowering the ‘B-Side Opponent’

Boxing trainer/manager Matt Nussbaum talks about how the Flex Mitts are changing how boxers train.

Flex Mitts training

For most, calling boxing the “Sweet Science” is simply a surface acknowledgment of the innumerable intricacies of the sport. For Matt Nussbaum, a forward-thinking boxing trainer and manager based out of New Orleans, focusing on the sport’s scientific aspect has yielded what may become his biggest contribution to the sport — The Flex-mitt training pads.

After years of exhaustive research on chronic shoulder pain in veteran trainers, Nussbaum devised the product to solve this issue while also maximizing the speed and pad durability needed to effectively train amateurs and pros alike. And when not spreading the good word on the Flex-mitts, he splits duties between training clients at New Orleans’ majestic Audubon Park and managing underdog fighters.

Nussbaum sat down with me to discuss the future of his invention and how the passion for protecting “b-side fighters” continues to drive him.


BeatsBoxingMayhem: With the Flex Mitts, how many people were involved in the creation of the product?

Matt Nussbaum: The origin of all invention is necessity. The idea started when I was managing heavyweight contender Fred Kassi here in New Orleans. He makes his money training people, so here you had an active prizefighter and small heavyweight doing 20-30 clients a day with mitt work. Because being explosive and fast is very important to a small heavyweight’s success, we needed to find a way to get the pressure and soreness out of his shoulders.

We went through all the high-end regular focus mitts and they all failed due to the fundamental reality that your body is connected to shoulders through the mitts. We started playing around with different ideas. Everyone usually goes to pool noddles, but the problem there is you can’t hit them. They’re great for defense but no so much on offense.

The same goes with padding. There’s a lot on the market from brands like Winning and Everlast. They’re good for speed and rhythm but you can’t really hit them hard and they break a lot.

The idea came when I took my dog to the park one day and watched somebody throw a tennis ball using one of those ball launchers. He said “Yeah, this saves my shoulder and I don’t have to throw it as hard. I can just put the ball in the top part and swing it.” That was my light-bulb moment. I can make something!

I made the first one from one of those leather ball throwers. We then had to figure out the right length, weight and balance. You can make short ones that are super quick, but they can’t absorb the same punishment. Heavier ones are more durable but you lose speed. We picked the Goldilocks version that was just balanced.


Once you had the product, how was the patent process?

We spent two years and an almost insurmountable amount of money to patent it. I have the patent. We sent a prototype to Timothy Bradley’s former trainer Joel Diaz out there in Indio, California. His feedback was instrumental in getting the length right. He was our first “pro tester.”

After Joel, things seemed to take off with Sugar Ray Leonard and trainer Virgil Hunter jumping on board and doing showcase videos.

Our target audience is usually trainers who have been doing it more than 10 years. We did a survey of about 100 trainers and I wrote a report showing if you’ve been doing this over 10 years there’s an 80% chance you’ve got significant shoulder pain.

Now, trainers are a stubborn lot and not quick to adapt to new technology. It’s ironic because those are the ones who need this the most. And most trainers are ex-boxers. If you have inflamed joints and pain, you’re already taught to push through it and not to let anyone know you’re in pain. That works in the ring but not as a long-term strategy as a trainer. You’ll ultimately wear that joint down enough to where your career will be cut short.

I’ve gotten letters from trainers stating the product has probably added 10 years to their career. That makes this all worth it.

Are there any new additions or products in the works to supplement or refine the Flex-mitt?

The next version will probably be a smaller “pro” one that’s a little faster but won’t absorb as much. You can use the current one for most needs but when training pros where you have to be super sharp, the smaller version would work great.

We have a Bluetooth punch-counter that goes on the mitts themselves. We have a few prototypes ready for sale right now at “flex mitts punch counter” at your Apple store and download it for free. You get the mitts with the sensors on them and it counts the left and right punches while keeping track of your work rate. You can set the timer and see how you progress session to session. This is really good for personal training and guys who like to track their progression without trying to count punches.

Let’s switch gears and discuss the “Boxing In the Park” sessions you do at Audubon Park. 

First off, I don’t have big classes. I usually have 1-2 people per session. The benefit of the park is being able to use all four square miles. I have a stage where I can do mitt work and 2-mile runs at the same time. We can hit stations for bars, then back to mitt work and sprints. There are so many options while keeping people’s heart rate up. It’s a great way to really pick up their cardio output.

I just love the park. It’s a new concept so I’m the only target — I don’t have any bags for them to hit.  I’m an “outdoorsy” type — a canoe and do swamp tours on the weekend kind of guy. I love boxing as well but I don’t like being in the gym.

Have you noticed any anecdotal evidence that your clients have better workouts when outdoors?

They  definitely get more cardio because we have more distance and I can vary it. In a  gym you can do circle drills and jump rope, but sometimes it’s hard to get that road work in combined with mitt work. I can keep the cardio more interesting when outside.

You mentioned earlier that you managed Fred Kassi? Who else is in your stable now?

Fred retired so now I have a light-heavyweight out of Atlanta named Michael Seals (22-2, 16 KOs). I think we have some big fights coming up. I also have Razvan Cojanu who’s fought on ESPN+.

Most will remember Kassi’s fights with Chris Arreola and Dominic Breazeale. As a manager, when you have an older fighter like Kassi was and put in an underdog position against younger and bigger fighters, how selective were you in choosing foes where he still had the chance for the upset?

Well, Fred is an amazing athlete. You can put him in with Breazeale, Arreola, or even Jarrell Miller and still get a competitive fight because of his athleticism despite sometimes giving up 50-60 pounds or 6 inches of reach.

For us, it was always about the money compared to the risk involved. We wanted to cash in on his ability to provide an entertaining fight. We always went to win and always thought we could. If you look at the Breazeale fight from a punches landed perspective, we felt we got robbed in there.

We know we’re not protected and the judges always went for the money. But Fred was awesome. Imagine having to fight guys three weight classes over you every time.

Michael Seals has KO power in both hands and can win at the elite level. We’re just looking for a chance to compete.


Final thoughts?

I love boxing but I really love being the manager of “opponents.” The boxing industry is rough on opponents and I feel it’s my mission to protect my fighters by getting them health insurance, being paid on time and the best shot they can to win. This is what I bring to the industry. Guys can get treated like meat  and I just don’t put up with it. You have to protect your guy.


For Flex Mitt purchasing and to book Matt Nussbaum for “Boxing in the Park,” visit the following sites:


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