From New Toronto, Lumsdon was coached by Gus Ryder at the Lakeshore Swimming Club. He turned professional when he was 16 and would later say that the only regret in his career was giving up his amateur status before the 1948 London Olympics. In 1949, at the age of 18, Lumsdon won the world marathon championship in Toronto, defeating 46 competitors in the annual 15-mile race at the Canadian National Exhibition. He won $6,300—$5,500 for winning the race and $800 for leading all laps and swimming the fastest lap. On the strength of that victory, he was awarded the Lou Marsh Trophy as Canada's top athlete of 1949.
Lumsdon would go on to win four more marathons at the CNE, including a 32-mile race along the Lake Ontario waterfront in 1955 (replacing a planned cross-lake competition). Lumsdon was the only one of 29 starters to complete the course—no other swimmer even made it to the half-way point. Lumsdon was accompanied for part of the race by his fiancee, and by fellow Lakeshore swimmer Marilyn Bell, riding in a boat. Lumsdon won $15,000 for his victory, plus thousands more in bonus money.
After two second-place finishes in previous years, Lumsdon won the 26-mile Atlantic City Around the Island marathon race in 1956. On 17 August of that same year, he became the second swimmer, after Bert Thomas, to cross the Strait of Juan de Fuca in British Columbia. He retired in 1965 with career earnings of $152,000.
He coached his daughter, Kim Lumsdon, who was also a top marathon swimmer, and accompanied her during her swim across Lake Ontario in 1976. He was inducted into Canada's Sports Hall of Fame in 1976, received the Order of Ontario in 1989, and was a recipient of the Order of Canada in 1982. In March 1988, a park in Toronto was named Cliff Lumsdon Park in his honour. He is the namesake for the Cliff Lumsdon Award, presented for outstanding achievement in marathon swimming in Ontario. Lumsdon died in 1991 at age 60.
Throughout his career, Lumsdon's last name was frequently misspelled as Lumsden.
International Swimming Hall of Fame Induction
As a member of the Class of 2013 in the International Swimming Hall of Fame, Lumsdon's induction is as follows:
FOR THE RECORD: FIVE-TIME WORLD PROFESSIONAL MARATHON CHAMPION: 1949-1954; ATLANTIC CITY 22 MILE (35.2K) PROFESSIONAL SWIM: 1st (‘56, ‘59), 2nd (‘54, ‘55, ‘58, ‘60, ‘62), 3rd (‘61), 4th (‘63, ‘64); 10 MILE CANADIAN NATIONAL EXHIBITION (CNE) PROFESSIONAL SWIMS: 1st (‘49, ‘50, ‘52, ‘53), 3rd (‘51), 5th (‘48); 1955 32 MILE CNE SWIM RACE: Only Finisher in Field of 35 Swimmers; STRAIGHTS OF JUAN DE FUCA: 1956.
Cliff Lumsdon was one of the world’s great long distance swimmers. He was five-time world champion between 1949 and 1954. He was known for his ability to swim in cold water, once going 32 miles in 18 plus hours in water temperatures ranging between 48 and 52 degrees F. His cold-water abilities were reflected in his 1956, 11 hour 35 minute crossing of the Straits Juan de Fuca between Washington State and Vancouver Island where water temperatures are reported to average 48 F. Cliff was the second person to cross the straits, after Bert Thomas in 1955. He completed ten Atlantic City Marathon Swims from 1954 - 1964, placing first or second in seven of them. He competed in six CNE swims in Lake Ontario winning four of them. In 1949, he won the Lou Marsh Trophy, for the outstanding Canadian Athlete of the year, and was inducted into the Canadian Sports Hall of Fame in 1976 as well as the Ontario Aquatic Hall of Fame in 1993. The Cliff Lumsdon Award is presented for outstanding achievement in marathon swimming in Ontario.
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