1. Going rogue on your outfit, fueling, or pacing choice
The phrase "nothing new on race day" is often repeated for a reason. Stick with what you know! Don't get caught up in what everyone else is doing. Make your plan, and stand by it. Wear the gear you've trained in, eat the pre-race breakfast you're used to, and run the pace you trained for.
2. Forgetting to charge your electronics
That GPS watch won't do you any good on race day if you forgot to charge it overnight. (Though you could always consider running naked.)
3. Not consulting the weather forecast
Nothing will threaten to mess with your big day like a mood swing from Mother Nature. But since you can't control the weather, do your best to adapt to it. Check the forecast leading up to the race so you can make sure you have whatever proper gear you might need—like a waterproof top if they're calling for rain, or hand-warmers if icy conditions are being predicted. If the day is looking hot and humid, dress the water and hydrate accordingly. Don't let the weather sideline all the hard work you've put in during training.
4. Lining up in the wrong corral
At big races, you'll be told where to line up, indicated by signs or a designation on your race bib. These guides exist for a reason. You want to start the race surrounded by people who run at a pace similar to yours. Start up front with all the fastest racers and you'll get trampled. Start too far back, and you'll be bobbing and weaving around people choosing to walk for the first mile. Find your people, wish them luck, and feel free to pass them in the final stretch if you're feeling fierce.
5. Going out too fast
When it comes to race-day mistakes, this one is a classic. It's easy to get caught up in the excitement and adrenaline of race day. But your first mile should, in theory, be your slowest. Many experts advise trying to negative split a race—meaning you run the second half faster than the first half. Go out conservatively, let people pass you, and then kick it for the second half. You don't want to gun it out of the gate only to be gasping for air within the first half-mile.
6. Blasting your music as loud as possible
Look, we all get psyched when Eminem comes on. But for your safety and the safety of those around you, if you choose to listen to music, keep your music at a moderate volume. You still need to be able to hear what's happening, and you should be aware of your surroundings and your body's signals. Use music for motivation if you want it, but not as a total distraction. Tune in, not out.
7. Not recovering properly
It's tempting to cross the finish line and proceed directly to brunch. (Or the shower. Or back to bed for that hard-earned nap.) But before you snooze or reach for the booze, take just a few minutes to let your body cool down and recover. For some runners, that means a short recovery jog (a mile or so post-race, depending on the distance), and for others it's a walk to find their family members followed by some stretching and foam rolling. If your race offers a massage area, go get one. If ice is your jam, ice and elevate your achy parts. If you're a Downward-Facing Dog-lover, flow through some light post-race yoga. Keep moving for a bit to let the lactic acid in your legs flush out, and to let your body come back to resting mode. Then, by all means, hit up the brunch buffet, the Bloody Mary, and the backyard BBQ.