McIntyre was born in Victoria, and was injured in a shooting accident when he was nine years old. His wheelchair basketball career began in 1968 when he represented Victoria at the National Wheelchair Games, where he was voted "best and fairest". He was then selected for the 1968 Tel Aviv Paralympics, where he won a gold medal in the Men's Slalom B event and participated in the Australia men's national wheelchair basketball team; he would go on to win medals at athletics events at every Paralympics until 1984, and participate in Australia's wheelchair basketball squad at every games until 1980. At the 1972 Heidelberg Paralympics, he won a bronze medal in the Men's Slalom 5 event, but did not win any medals at the 1976 Toronto Games. He also represented Australia at the 1970 Edinburgh and 1974 Dunedin Commonwealth Paraplegic Games.