Recommended by the world's top athletes & coaches

Michael Andrew


“Adding the GMX7 X1-PRO to my regular training programs has helped me gain strength in my strokes quicker, while being able to maintain specific movements in the water under load. This ultimately leads to faster swimming, and more confidence in the power being produced through each stroke taken.”

Ryan Lochte


“The X1-PRO is the best resistance training tool I have ever encountered throughout my swimming career. This device is a game-changer for all types of swimmers. If you don’t have one you are falling behind!”

Caeleb Dressel


“I’m sincerely thrilled my relationship with GMX7 is now official after training with their product over the past few years. I always look to form partnerships with businesses and organizations that I believe in—who support me. GMX7 joins a list of sponsors that do just that.”

Sergio Lopez

Virginia Tech - Men’s and Women’s Head Coach and Olympic Coach

“The X1-PRO is an essential resistance training tool that every coach should have. It is very simple to set up, easy to maintain and barely uses any storage space. You can use it every day to work on developing power/speed on the start, turns, underwaters and breakouts. Also a great tool to use with low resistance to work on technique correction and stroke awareness. The fact that the X1-PRO is so portable makes it an essential piece of equipment to take to training camps and competitions to be able to keep working in developing and improving the stroke technique and conditioning.”

Jake Shellenberger

Liberty University - Head Coach

“We love our X1-PRO’s at Liberty and we use them 3-4 times per week. Coaches are only limited by their creativity when using this device. Whether for pure power, post-activation potentiation, power endurance, kicking, or drilling, the X1-PRO delivers it all. In regards to power endurance specifically, the ability to go 50 meters is a game changer, and the X1-PRO is just as beneficial for distance swimmers as it is for sprint types.”

Matt Barany

University of Richmond - Women’s Head Coach

“The Richmond women immediately commented on the deceptively smooth resistance. The coaches are excited, as these compact devices do not clutter our small pool deck. Further, the X1-PRO appears to have limitless applications and we’re inspired to re-imagine our training at Richmond.”

Bob Bowman

Olympic Coach and Mentor to Michael Phelps, & Head Coach of Women's Swimming & Diving at Arizona State University

“GMX7 and the X1-PRO is an amazing product, I would highly recommend it.”

Chris Dahowski

Paseo Aquatics Head Coach

“As a coach, one thing I am always looking for is feedback and communication with athletes. The Pro1’s have stimulated conversations about post-action potential. In the right minds, the X1-PRO’s are far more than just resistance training. We are discovering possibilities daily.”

Jeff Dugdale

USA Swimming Coach of the Year, USA National Team Coach / Six-Time CSCAA Coach of the Year / Eight-Time Bluegrass Mountain Conference Coach of the Year / Winning Coach of last 5 DII National Champions

“X1-PRO has been an Excellent tool in developing our underwater kicks as well as using to ”set” the catch in our strokes, different than tubing or racks, the leash does not inhibit the range of kicks. We love it.”

Dan Jacobs

Head Coach - Machine Aquatics

"This is an awesome product and training tool. We don’t have much room and no storage at most of our facilities. Having the ability to train resistance daily and literally pull the equipment out of my backpack is fantastic! I highly recommend this product."

Coach David Marsh

Olympic Swim Coach

“The X-1 PRO has been an invaluable tool in many ways for our Team Elite Professional and Age group swimmers at StingRay aquatics. The smooth consistent resistance can be dialed up for challenging short blast efforts or can be dialed down to add a small load. In addition, our swimmers are constantly using the device to work on stroke corrections. I have my X1-PRO’s in the water daily and it has been a tremendous addition to our program.” 

Mark Schubert

Olympic Swim Coach

“GMX7 and David McCagg have created something very special in the X1-PRO. The features are insane and every athlete needs to be resistance training on it!”

Coach Greg Troy

Olympic Swim Coach

“GMX7 is changing the landscape of resistance training forever. The X1-PRO is a GAME CHANGER and our pro’s trust in the results they’ll achieve with the X1-PRO.”

Coach Ira Klein

Sarasota Tsunami Swim Team

“From the beginning I had the pleasure of watching and testing the new X1-PRO through its entire inception and design.  GMX7 and David McCagg have definitely developed a new product that will revolutionize resistance training for everyone.  Age group through international level competitors will benefit greatly from this new invention.  We have been using it with our swimmers for some time now and with it being fully available it will become the center piece for our resistance training.”

Clark Carlson

Coach & Owner of Swimtek (Perth, Australia)

“The GMX7 Pro is a game-changer and has reinvented training and not just resistance training. It is the best overall coaching/training accessory I have used. It improves all aspects of swimming, as it allows resistance training to be integrated easily throughout sessions with easy set-up, quick and simple change for distance, stroke and swimmer. I have been using the X1-PRO across all aspects of training including dives, breakouts, and turns and I am seeing huge improvement across all levels of swimmers. It has really changed the way we train.”



“As a sprinter, resistance training is a huge part of my day-to-day routine, and the X1-PRO allows me to push myself to new limits that you just can’t reach on other resistance tools. Using the X1-PRO has really taken my training to the next level.”

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