Thomas won multiple individual honours at World Championships, European Championships and Commonwealth Games, collected an Olympic bronze with the British team at London 2012.

The 28-year-old, from Wolverhampton, was part of the five-man squad that won Britain's men their first team medal for 100 years. 

Thomas also captained the team in Rio 2016 and led the men’s artistic British team for over a decade, being an integral part of many of his country's defining moments in the history of men’s gymnastics.

A member of the Halesowen-based Earls Gymnastics club, Thomas told british-gymnastics, the website of British Gymnastics: “I think now is the right time, having achieved everything I’ve ever dreamt of in the sport, being lucky enough to compete at the highest level, win medals for my country and travel the world with my friends. 

"Now is the time to try something new and hang up the guards. 

"I started gymnastics 23 years ago and I’ve always found it exciting, challenging and unique which is what has kept me in the sport so long.

"In terms of my best moments I could make a list that goes on and on but the three occasions that really stand out for me would have to be the London Olympics, 2015 Glasgow World Championships and winning a bronze on vault at the 2013 World Championships. 

"All for very different reasons, but the magnitude of a home Olympics and the feelings and emotions of what it’s like to win an Olympic medal is something that I will never forget. 

"It was similar with my 2015 World Championships experience. 

"To win medals in front of a home crowd, and to do it as team captain made the moment even more special.

"The World Championships vault medal was one of my most rewarding because of the journey I’d had that year. 

"A broken tibia, broken heel bone, tough team selection, yet I came through it and this helped me to further achieve international medals.

"To end my competitive career in Rio and be selected by my peers as team captain is something I’m extremely proud of. 

"I’ve been fortunate enough to compete alongside so many incredible and inspirational gymnasts who know how to get the best out of each other; that made my role as team captain the easiest of jobs.

"I want to thank all the incredible people who have supported me every step of the way. 

"My coaches, family, friends, British Gymnastics support staff and the amazing gymnastics fans. 

"I will definitely be staying in the sport and look forward to cheering on the British team for many years to come.”

Thomas initially announced his decision on on his 'kristom1' page on the social media platform Instagram. 

His post said: "So the day has finally come where I officially hang up my guards. 

"It’s been an incredible journey over 23 years. 

"I can finish the sport extremely proud knowing I’ve become an Olympic, World, European and Commonwealth Medalist, something most people only dream of. 

"So on that note, thank you to everyone that has helped me achieve my dreams. 

"I couldn’t have done it without people being in my corner, and I will always be grateful for the support I’ve had from coaches, to family, to team mates to medical staff. 

"Special thanks to Michelle Baker and Andrei Popov for all their input in getting the very best out of me. 

"My wife & family Gemma, Mum, Dad Ashley and Rebecca, who have been on this exciting adventure with me every step of the way. 

"Gymnastics family, I’ll still be about so see you all around!"