What Tom Brady’s body coach, business partner says was the key to the quarterback’s longevity

After 22 seasons in the NFL, Tom Brady officially announced his retirement from the sport that widely considers him the greatest quarterback of all time.

"There is a physical, mental and emotional challenge EVERY single day that has allowed me to maximize my highest potential. And I have tried my very best these past 22 years. There are no shortcuts to success on the field or in life," he wrote in a statement on Instagram Tuesday. "My teammates, coaches, fellow competitors, and fans deserve 100% of me, but right now, it's best I leave the field of play to the next generation of dedicated and committed athletes."

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The best of Tom Brady

After 22 seasons and seven Super Bowl wins, Tom Brady is retiring from football.

ABCNews.com

Brady, 44, personally thanked his longtime friend, body coach and business partner Alex Guerrero in the post, writing: "I could never have made every Sunday without you; it's that simple. Your dedication to your craft and our friendship and brotherhood are immeasurable. We have an unbreakable bond, and I love you."

Guerrero spoke exclusively to "Good Morning America" on Wednesday about why Brady finally decided to hang it up and what he believes has been the key to Brady's longevity and success in the league.

"I've been fortunate enough to work with a lot of high-end athletes and have taken several into retirement," he said. "Some are really prepared for it and others aren't -- I think he's excited about [his] post-football career. He has amazing businesses he's involved in. Certainly, he has a passion for health and wellness and sharing the TB12 method and what we have been able to share with the masses and how to be able to do it regardless of age."

When it came down to the decision for Brady to call his season with the Tampa Bay Buccaneers his last one, Guerrero said it was a culmination of decades of dedication.

"I think he's gotten to the point where he realized that he just wanted to spend some time with his family and give back," he said. "When you take the time with him and you see how committed he is to the things that he loves doing, which for 22 years was football and for the season he was so dedicated to his team and wanted to be the best for his teammates -- now just like Tom said, he wanted to take time to reflect and find a direction for his path moving forward."

Guerrero said, "up until last week," Brady remained focused on the team and "being the best for his teammates."

"I think the key to his longevity obviously is his work ethic, healthy habits and his winning mindset," Guerrero listed. "Working on the physical body, the emotional body, the mental body -- I think through our work together through his training, through our manual therapy, all the body work we've done to really prepare his body to be able to sustain the impact that the sport put on him over the course of, you know, all these 16 years together, I think that really goes towards talking about his longevity and why he was able to do it for as long as he was able to do it for."

He continued, "People in the future will be able to hear more from him and see more about how he did it and why he did it and the results of doing it."

Brady won Super Bowls, the most championships won by a single player, along with five Super Bowl MVPs.

He also rewrote much of the NFL record book between both personal and team accomplishments with career records such as most touchdown passes (624) and most passing yards (84,250) in his 22 seasons -- 20 of which were with the New England Patriots.