Henricks began his competitive swimming career as a distance freestyle swimmer. He scored his first notable successes at the 1952 Australian national championships, when he came third in the 1500 metres, second in the 800 metres, and first in the 400 metres. A prolonged ear infection kept him off the 1952 Australian Olympic team. His coach
Harry Gallagher converted him to sprint freestyle events, and he bettered the Olympic record for 100 metres at the 1953 Australian national championships. He held the 100 metres long-course world record for five years, winning gold medals in the 100 metres and 4×200-metre freestyle relay at the
1956 Summer Olympics in Melbourne. During those five years, he lowered the pre-existing record by almost two seconds. During that time, he won ten Australian individual championships in those events, two
British Empire Games medals and establishing new records in 1954, the Japanese Nationals, the Keo Nakama meet in Hawaii, the Philippine Nationals, and broke two American records while on a visit in 1954. He was named Australian Athlete of the Year by the Helms Hall of Fame in 1955. In 1958, he won the American outdoor national championships in the 100 and 200 metres. After the 1956 Olympics, Henricks enrolled in the
University of Southern California (USC), where he was a member of the
USC Trojans swimming team. As a freshman at USC, he teamed with
Murray Rose,
Don Reddington,
Tom Winters and
Denis Devine, a five-man freshman team that broke the New Haven Swim Club's dynastic grasp on the
Amateur Athletic Union (AAU) indoor championships. The USC freshman team grew into a collegiate powerhouse in the late 1950s and 1960s, dominating the
Pacific-8 Conference, winning the
National Collegiate Athletic Association (NCAA) team championship in 1960, and laying the groundwork for greater success. In 1960 Henricks made another attempt at the Olympics, winning the Australian trials handily. Henricks contracted a gastrointestinal ailment at the Olympics in Rome and was eliminated in Semi Final 2, finishing fourth. Australian
John Devitt and American
Lance Larson were left to contend. Both were teammates; Larson on his USC team, Devitt on his Australian team. ==Personal life==