The key to fast transitions is to stay calm and relaxed, and practice them before race day.
You can start to unzip your wetsuit while you make your way up from the water. Once by your bike, remove your wetsuit completely. Put your helmet on and be sure to buckle it. Put on your shoes (and socks if you're using them) and sunglasses. Some races require that you wear your race number on the bike; be sure to check the rules of your race.
Grab your bike and make your way towards the bike exit.
Wait until you get the mount line to get on your bike. Start out slow even though you'll be excited.
Wait for about 5 to 10 minutes before eating or drinking to let your nerves settle. Then, be sure to eat and drink regularly, according to the fueling plan you developed in training. Many athletes get so caught up in the race they forget to take in fluid and calories, which can lead to sub-par performance or bonking.
Ride to the right hand side of the road at all times (unless you're passing). Keep at least three bike lengths between you and the person in front of you.
In the last few minutes of the bike leg, shift to an easier gear and spin easy to get your legs ready for running. Do not hammer into T2.
Brake early to ensure you'll safely stop before the bike dismount line.
Make your way to your bike rack, rack your bike, and then take off your helmet.
If needed, put on your running shoes. If you choose to go sockless, be sure to put baby powder in your shoes and lubricate your feet.
Grab your nutrition, race number belt, hat or visor, and make your way to the run exit. Once again, the key to a fast transition is staying calm and relaxed.
It's likely that you'll be uber excited at this point, so be sure to start slow. It's much better to start slow and speed up as the race goes on than to start off too fast and blow up during the run.
Be sure to drink at every aid station and take your nutrition as practiced during training.
It's during the run where many athletes struggle. Think about why you are racing; try to have fun, and even smile.
As you approach the finish line, be sure your race number is facing the front.
Once finished, get your medal, turn in your timing chip, and grab something to eat and drink to re-fuel. Give yourself a pat on the back for a well-executed race.
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