A sprint triathlon typically consists of a swim portion that is around 500 meters (about a half mile), a 20K / 12.6 mile bike ride, and a 5K or 3.1 mile run. How do you train for this? Simply put, you do work outs in all three disciplines each week. As a beginner, in every workout session, you need to work on one of two things: endurance and technique. A triathlon schedule needs to include training that works on both of these areas.

Here is an example:

You have 3 swim sessions scheduled for the week. Swim session 1 and 3, you should work on better swim techniques. Do drills that focus on arm stroke (like one arm crawls with a pull buoy), breathing (proper head placement), and leg stroke (using a kickboard). Concentrate and work hard on drills and rest between different drills. then for swim session 2, work on endurance. Try to do at least 20 laps at a easy-but not lazy-pace.

This is just an example. You will want to do this for swimming, biking and running--practice better technique and increase endurance. It is obvious why you want to increase endurance--you need to last a while to get through a triathlon. And the temptation of many beginning a triathlon training schedule is to just work on endurance. But it is just as important for the beginner to work on technique for a couple of reasons. One, as your technique gets better, i.e. more efficient, you waste less energy when you are running/swimming/biking. More energy, the longer you can go without fatigue.

Two, as you improve your technique, you will get faster. Now let me stop you, you are not worried about speed for your first triathlon. You should be focused on finishing and getting used to the whole event. But after you finish that first tri, your thoughts will go immediately to how can I do better? Start getting good habits and good form in place, your speed will naturally increase a bit, and you will be ready for when you really want to start increasing performance.

There are several good sites that list good mechanics and drills for swimming, biking and running. Don't go overboard at first. Pick a few drills that make sense to you and the level where you are. Just make sure you incorporate drills as well as endurance training in your triathlon schedule, and you won't be sorry.