Technology has also had a big impact, especially on the bike. Now everything is tested aerodynamically, wind tunnels are used to optimize performance, and frames, wheels, water bottles are all tested. Even clothing, like my Castelli Stealth Top, is faster than skin.

When I am at my limit and hurting, I focus on the moment.

When it hurts, you can't think of the entire picture. If you break it down to the moment, it becomes manageable.

The sport is definitely growing, and has become much more competitive. When I started, you were either a former swimmer or runner who took up triathlons. Now, you have a generation of triathletes coming up that started competing at a young age - these are the people that will change the game.

I like to compete in a suit that will help me save me time and energy by reducing drag, so I race in Aqua Sphere's Energize Compression Speedsuit. The speedsuit also compresses the core muscles to damp vibration, which lessens muscle fatigue, leaving me fresher for the bike and run.

My favorite piece of tech gear is my SRM power meter. It's the most accurate power meter on the market.

The Ironman World Championship is the hardest race I've competed in. Not only do the elements (heat, wind, humidity) make it grueling, but the quality of the field makes it a true test.