Wallace took up skiing as a teenager, after a school ski trip. After working on an artificial slope, he joined the Southampton freestyle skiing team. Wallace came second at a junior ski ballet international competition. Wallace competed in the FIS Freestyle Ski World Cup between 1981 and 1989. He finished in the top 10 at 22 events, and was at one time ranked sixth in the world. In 1984, Wallace was involved in a ski dancing and acrobats event at the Earls Court Exhibition Centre. Wallace came sixth in the combined event at the 1986 FIS Freestyle World Ski Championships. Wallace competed in the freestyle skiing demonstration event at the 1988 Winter Olympics. He was considered one of the favourites. Later in the year, he was suffered knee ligament damage during an event at the Earls Court Exhibition Centre, which sidelined him for six weeks. Fellow athlete Mike Whealey suffered a career ending injury at the event.