How to Stuff Your Face Before a Race

When you're training, you should aim to get more than half of your calories from carbohydrates, a quarter from protein, and the rest from fat, says Ryan Maciel, RD, the Head Performance-Nutrition Coach for Precision Nutrition.

Carbs, which are stored in your muscles and liver as glycogen, should make up a large portion of your diet because they're your body's most readily accessible source of energy. That's why carb-loading is a go-to method for runners who want to top off their glycogen stores before a big event.

But take your fork out of your farfalle. Carb-loading does not mean inhaling straight carbs for the entire month before your event. Or, perhaps worse, only the night before it. If you're running a race in under 90 minutes, like a 5K or 10K, you don't even need to overstock on carbs, says Monique Ryan, RDN, a sports nutritionist who advises professional and endurance athletes and teams. And if you are running a longer race, like a half-marathon or marathon, there's a narrow window in which to do it.

About three or four days before your event, shift the makeup of your meals to 70 or 75 percent carbs, still leaving room for protein and healthy fat, says Maciel. Your body can't top off glycogen stores in one night, and overdoing it on Cs right before your race could leave you feeling sluggish, the opposite of what you want.

Ideally, you'll "train" for this kind of fuelling the same way you do for the race itself—especially in the days leading up to some of your longest runs—so you know what's going to work for you, says Ryan. Come race day, you don't want to face any surprises before (or worse, after) crossing the starting line.

You may have running friends who swear by a pre-race fried-egg sandwich, and others who promise that's the worst thing you could eat. There are no "wrong" or "bad" foods to eat before an event, says Maciel, just ones that do or don't work for you. The only rule you should stick to? "You don't want to try anything new before a race", says Maciel. "You should be doing what you've practised over the past several months of training". Why? Putting it kindly, stomachs can be unpredictable, especially when they're filled with race-day butterflies (those starting-line porta-loos are proof).

That said, the majority of runners do well when they avoid foods that are heavy in fat or fibre or are overly greasy, says Maciel (so maybe rethink that bacon). These take longer to digest, which can overtax your stomach and cause gut problems while you're running.

Food matters, but to get the most out of your training, you have to hit the H20. You should be hydrating all the time, and particularly in the weeks leading up to your event, says Maciel. You can't carb- or water-load: "Chugging water the night before a race is not going to make up for not hydrating enough all those other days", he says. In other words, if you trained while slightly dehydrated, you just won't have the fitness you could have had if you'd taken in more fluids. Plus, chugging too much the night before or the morning of the run will likely make your stomach slosh—and just make you have to pee more than usual.

Some runners like to make a point to increase and track their water intake every day during the week of their race, and others like to add an electrolyte supplement the night prior to boost their hydration even more. As long as you're drinking at least eight glasses a day (pro tip: set a reminder to drink a glass every hour of your workday), you should be in good shape, says Maciel. Like training for the perfect pre-race meal, you want to train for your ideal level of hydration too.

Now that you know what to eat (and what not to), maybe you should go invent that meal-delivery app. After you crush your race, of course.