It takes most first-timers just under two hours to complete a tri, so look for one with generous finish times. ( TriFind.com is a good source.) Also, choose a lake or pool course (versus ocean), so you won’t have to battle big waves or heavy currents.
It’ll take five to six workouts per week for 12 weeks. A suggested schedule:
Swim: Hit the pool twice a week to swim your race distance. Can’t finish the entire segment? Break it into parts at first, but make sure you cover the distance continuously at least once before race day.
Go for an hour-long ride one to two times a week and practice your pedaling technique (keeping constant force throughout the cycle), as well as how to smoothly change gears on both flat and hilly terrain.
Spinning classes will help you develop stamina and can replace an outdoor session.
Work up to running 3-milers one to two times a week. Also, once a week do a bike-to-run "brick"—cycle for 20 to 30 minutes, then immediately do a 1- to 2-mile run. Bricks will improve your endurance and get your body used to running on tired legs.