An athlete from the start, he dedicated his teenage years excelling in soccer. He had no interest in bodybuilding until, at age 16, Park met a muscleman named David Cohen. Upon learning that Cohen lifted weights at his friend's house, Reg Park joined in with curiosity. Park's legendary physique would grow from barbells, dumbbells and a simple chinning bar.
Upon discharge from the military in 1948, he saw his very first physique contest. This was the inaugural NABBA Mr. Universe contest, in which John Grimek edged out over Steve Reeves in controversial fashion. It was this contest that inspired Reg Park to compete himself.
After one year of hard training, Reg Park earned the title of Mr. Britain in 1949. He then subsequently spent six months in the United States (thanks to a gift from his parents). There, he met up with famed publisher Joe Weider, who began to feature the Englishman prominently in his muscle magazines. The next year, Park was runner-up to Steve Reeves in the 1950 NABBA Amateur Mr. Universe in London (also a close contest).
After a second full year of training, Reg Park broke what had been an American monopoly on bodybuilding titles by winning the 1951 National Amateur Bodybuilders Association (NABBA) Amateur Mr. Universe. He cemented his superstar status by winning the 1958 AND 1965 NABBA Pro Mr. Universe titles. Standing 6'1" and with a top weight of 250 pounds, Park was known for his muscular mass that was the forerunner to modern bodybuilding today. Park was also renowned for his strength, which he often demonstrated in contests and strongman exhibitions. It is on record that he was the first bodybuilder to bench press 500 lbs.
Famous for his mass and strength, Reg Park was an early influence and lifelong mentor to champion bodybuilder and current Governor of California Arnold Schwarzenegger. Bonus footage from the DVD release of the classic documentary film Pumping Iron (1977) features Park mentoring Schwarzenegger. Park can also be heard performing the Master of Ceremonies duties in the Mr. Universe and Mr. Olympia Contests featured in the film proper.
As an actor, Park made five films — all Italian Hercules sword and sandal.
According to Canadian professional wrestler Bret Hart, Reg was a good friend of his father Stu Hart, and was responsible for designing many of the buckles and plates for most of the championship belts of the World Wrestling Federation.
Reg Park's legacy is continued by his son, Jon Jon Park, a personal trainer and former Olympic swimmer. Reg Park raised and trained Jon Jon in South Africa. Today Jon Jon Park is the owner of the Legacy Gym, a popular gymnasium in West Los Angeles, CA. Reg's daughter, Jeunesse, runs the Reg Park Legacy Foundation which helps disadvantaged people access sport and fitness.
Up to the time of his illness in 2007, despite being in his seventies, Park continued to train clients at the Morningside Virgin Active Gym in Sandton, South Africa. He has been featured in many fitness and bodybuilding magazines, and has also appeared on the cover of MUSCLE magazine. He was inducted into the International Federation of Bodybuilders (IFBB) Hall of Fame's first ballot in 1999.