With a few notable exceptions (professional and elite short-course racing), it is illegal to draft in triathlons.  However, the specifics of what exactly is considered drafting are a bit confusing.  If you’re a new triathlete, it’s particularly important for you to understand the drafting rules, primarily for your safety and secondarily to maintain the ethics of the sport.

So, what is “drafting?”

• When cycling, riders must keep their bike more than 3 bike lengths of the rear wheel of the rider in front of them. 3 bike lengths is a long distance.  Get out your bike, pace off 3 meters (10 feet) and visualize what that distance looks like.  There is one (AND ONLY ONE) exception to this rule.  See the next point.
• If you want to pass the rider in front of you, you may do so.  You have FIFTEEN (15) seconds to pass the rider. During this time you may enter the 3 bike length draft zone.  ”Passing” is defined as the front wheel of your bike overtaking the front wheel of the other athlete’s bike.
• Once you have passed the rider in front of you, the other rider has FIFTEEN (15) seconds to drop back to the legal distance of 3 bike lengths. To assist in this, continue to maintain your speed as you pass the rider.  That way, the overtaken rider doesn’t have to hit the brakes to get behind you.
• If you get closer than 3 bike lengths to the rider in front of you, you MUST pass the athlete.  If you do not, you will get a drafting penalty. You CANNOT approach the rider and drop back without passing.  There is only one way out of the draft zone, and that’s by passing the rider.  (The reason behind this seemingly unusual rule is this–even at 3 bike lengths, there’s still a noticeable drafting benefit.  If this rule did not exist, an athlete could “hover” between 2 and 4 bike lengths behind a rider for an extended duration, getting a nice draft in the process.)
• If you take longer than 15 seconds to drop back to 3 bike lengths after being passed, you will get a drafting penalty. Men, if a lady is passing you let her go.  Don’t try to catch her.  You’ll only humiliate yourself and get a penalty in the process.
• During your 15 second passing period, you may be anywhere within the draft zone.  It is LEGAL to get right behind the rider you’re about to pass and then “slingshot” around him or her–provided you do it all within 15 seconds.
• During this whole process, you must stay as far to the right as is practicable.  When you’re riding on your own you should be to the right anyway.  When you’re passing an athlete, you should pass on the left, but stay as far right as you can.  Certainly, do not cross the yellow line.  After passing, move back to the right so as not to be in a “blocking” position (riding too far to the left).
• It is polite (but not required) to announce “on your left” as you are passing the rider.  Give the rider plenty of advance notice so they don’t get startled and swerve into you as you’re trying to pass them.

Even if the race you’re doing is crowded and/or flat, if you can follow these rules, not only will you avoid costly penalties, but you’ll be improving everyone’s race experience–including your own!