Complex sentence: The event had been a staple of strongman competitions from their earliest days, with the 1980 World's Strongest Man contest, seeing Bill Kazmaier, hoist 157 kg to win the event and set a world record.
Split into simpler sentences: The event had been a staple of strongman competitions since the early 1980's. Beginning with the 1980 World's Strongest Man contest, Bill Kazmaier hoisted 157 kg to win the event and set a world record.