Postwar England, where food shortages were common and fitness equipment was rare, was the unlikely place from which Reg Park conquered the world of bodybuilding, becoming the first non-American Mr Universe and a legend among musclemen.

Among his most fervent admirers was a young Arnold Schwarzenegger, to whom Park became an inspiration and a mentor. Park's success, not least as the star of five Hercules films, was the spur for Schwarzenegger's own career, as he always acknowledged.

Park was born in Leeds, the son of a gym owner. He showed early athletic promise and attracted interest from Leeds United Football Club, but he was soon committed to bodybuilding. “I was a very timid youngster but I began buying magazines and acquired a burning desire to be the world's best-developed man,” he recalled. Much of his early training was done using lead-filled sacks as makeshift weights.

After National Service in Singapore, where he become a physical education instructor, Park was spurred by attending the 1948 Mr Universe competition, held that year in London. Training at night in his parents' garden, the six-foot Park bulked up from 185lb to 227lb within a year. This was no small achievement at a time of rationing and rudimentary training techniques — and before the advent of steroids. “My workouts put such a stress on my nervous system I couldn't sleep,” Park recalled. “My body would twitch and jump all night long.”

He won Mr North East Britain and Mr Britain in 1949, which brought him to the attention of Joe Weider, the owner of several US bodybuilding magazines, for which Park started to pose. In 1950 he entered Mr Universe and came a close second to the American Steve Reeves, before winning in 1951.

This set him up on a career of guest appearances, demonstrating his bulging physique and phenomenal power — he claimed to be the first person in the world to have bench-pressed 500lb, in 1953.

In 1958 he competed again in Mr Universe as a professional — the first time that a previous winner had done so — and duly won. This was the springboard for a move to South Africa, his wife's homeland, where he opened the first of a chain of gyms.

In 1960 he was invited to Rome for a screen test as Hercules, in succession to Reeves, which led to starring roles in five “sword-and-sandal” epics.

“I don't even remember their names,” Park said in 2000. “I never fancied myself as a movie star.”

In this he differed markedly from his young protégé. Schwarzenegger clipped Park's pictures from magazines in the early 1960s and determined to emulate him. “That man was an animal,” he said. “That was the way I wanted to be ultimately — big.” He went to train in South Africa, where Park welcomed him into his family and imposed a punishing regime: “I'll always remember him making me do calf-raises with 1,000lb at 5 o'clock in the morning,” said Schwarzenegger.

Schwarzenegger burst on to the bodybuilding scene at the 1966 Mr Universe, the year after Park won it for a third time. He won four times in a row from 1967, narrowly beating Park in 1970. Park stayed close to Schwarzenegger as he sought a Hollywood career, and in 1989 confidently predicted that his protégé would become Governor of California.

Park himself continued on the posing circuit. His graceful posing routines — developed with his wife, Mareon, who had been a ballet dancer — set a new standard in a world where bulk had always trumped artistry.

Park is survived by his wife, a son and a daughter.

Reg Park, bodybuilder, was born on June 7, 1928. He died of skin cancer on November 22, 2007, aged 79