Now that you know what NOT to do, here's what you should do instead:
Focus on your breath. Yes, I know you were planning to breathe throughout the day. But this is about taking deep breaths when the gun goes off. This will help you avoid spiking your heart rate, which is likely creeping up a bit from the excitement of the moment. Deep breathing will also help you to stay in control and build into a solid swim pace at a comfortable effort.
Ride one gear easier than you can hold. This tactic lets you build into your pace without over stressing your body during the transition from the swim to the bike. It works particularly well in long course races because physically and psychologically you're building momentum and you can count on having more in the tank as the day goes on. Combine this tactic with good pacing and you're well on your way to a faster run split.
Spin more in the last few miles. When that "horse to the barn" syndrome sets in its hard not to push big gears to finish the bike leg FAST. Try instead to increase your cadence up to 90 RPMs or more in those last few miles to loosen your legs and prepare them for quicker turnover in the run.
Stretch before T2. In those last few miles take a moment to stretch out your back and calf muscles. Just stand up and lean your hips forward to loosen your back muscles and then drop each pedal one at a time to the 6 o'clock position and push your heel down to lengthen your calf muscles. This will make it a little easier to jump off your bike, dash into T2, and transition to an upright running position.
Focus on fast leg turnover first. If you want a faster run leg you need to start with a higher leg turnover. The reason is simple: after the swim and bike your legs will be tired and your stride shorter. Your best weapon at this point is a quick cadence that uses your cardio system more than your leg strength. That way you have a better chance of holding your pace through the second half of the run.
Talk to yourself?positively. To help you get into a good run rhythm it's a good idea to have something in your quiver that gets you focused. You can count your breaths, repeat a word or phrase like "quick" or "smooth and strong" to yourself, repeatedly count from one to four, hum or sing a favorite song, and by all means smile! Remember there's no right or wrong; there's only what works for you.
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