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

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.

Ironman distance triathlons are a true test of oneself as a whole. Each race is a test of physical, mental and spiritual toughness that I haven't found in any other type of racing. At the end of the day, challenging myself on all levels is what it's about for me.

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

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.

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.

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