The IndyCar drivers are now Ironmen.
Both drivers finished one of the most grueling endurance races in under 13 hours.
The Ironman World Championship includes a 2.4-mile ocean swim, 112-mile bike ride through hot ancient lava fields and a 26.2-mile marathon.
The drivers joined more than 1,850 triathletes in Saturday's race.
Meira clocked in at 12 hours, 24 minutes and 2 seconds; Kanaan finished in 12:52:40. Meira was 1,407th and Kanaan was 1,486th overall.
A total of 1,918 triathletes started the race, including 50 professional men and 30 professional women.