Jenner was an outstanding school athlete; bagging a clutch of titles in American football, basketball and even water-skiing.
He was on a football scholarship at a small college in Iowa when coaches suggested he take up the decathlon, the toughest Olympic event of them all.
Within a year he had qualified for the US team and was headed for the 1972 Games in Munich at the age of 23. He finished 10th in Germany, over 700 points behind the Soviet Union’s Mykola Avilov.
That defeat prompted Jenner to change his training regime and instead of honing his skills alongside fellow decathletes, he would practice with the best team-mates he could find in each discipline. As a result his results improved markedly.
He was crowned US champion in 1974 and 1976, and then headed for the Olympic Games in Montreal as one of a small group of athletes fancied to win the biggest title of them all.
With many of his stronger events featuring on day two, it was a strong first day that proved the key to Jenner’s ultimate success.
The Ukrainian-born Avilov was equally intent on putting himself out of reach by the time the field went to bed on the first night, but it was the American who always had the upper hand.
Jenner was only one of nine athletes, including Great Britain’s future two-time Olympic champion Daley Thompson, to run sub-11 seconds for the 100m, however he then lost out by 60 points to Avilov in the long jump.
Jenner closed the first day in spectacular style, finishing second in the shot put, high jump and 400m to lie just a handful of points behind Avilov.
Day two turned into a procession with Jenner putting in a string of great performances. He lost ground on Avilov in the opening sprint hurdles but immediately won it back by hurling the discus to a mark of 50.04m, almost three metres further than his nearest rival.
By the time the field lined up for the final event, the 1,500m, Jenner had a handsome lead and the world record was within reach.
He finished the three and ¾ laps with the second fastest time. The gold medal, and with it a new place in the record books, was his.
He finished on 8,618 points, over 200 points clear of German’s Guido Kratschmer, with Avilov having to settle for bronze.