Frank Stack was born to a notable athletic family in Winnipeg. Stack's father Jack, himself a highly rated speed skater, entered his son in competitions at the age of 13. Stack became a powerful, tireless skater with quick acceleration that filled his trophy room.
Stack made his first great impression on the Canadian speed skating scene when he captured the Senior Men's title in 1931 at the North American Indoor Championships in Chicago. Stack set a World Record for the Five Mile race at 15:42.2. Later that year, Stack won the United States National Outdoor Championship. In 1932 and 1938, Stack won the indoor title and in the intervening years was the runner-up. During 1934, Stack competed alongside Canadian Alex Hurd in international meets in Norway where he won twice and placed well overall.
Stack won the Canadian skating championship six times. His last Canadian title in 1954 was also his last year of competition. Stack was chosen six times to represent Canada at the Winter Olympics as a competitor or official. In his first Olympiad at Lake Placid in 1932, Stack placed fourth in the 500 and 1500 metres and won a bronze medal in the 10,000 metres. Although he was named to the Canadian team in 1936, Stack did not attend due to a lack of funds. The 1940 and 1944 games were cancelled due to war but in 1948, Stack took sixth place in the 500 metres. As a coach and athlete on the 1952 Canadian team, Stack placed a remarkable eleventh in the 500 metres at the age of 46. In 1960, Stack was Manager/Coach of the skating team at the Olympics in Squaw Valley, California. In 1965, the Canadian Speed Skating Association established its own Hall of Fame and Stack was one of the five charter members.