(CNN) -- "Diet and exercise" is a phrase that goes hand-in-hand with losing weight. But what you eat or drink before, during and after your workout is key to the weight loss process.
Whether you run marathons, bike to work or walk around your neighborhood a few times a week -- if you really want to optimize your workout, it's time to check in on your diet.
It's all about moderation and balancing your food groups: protein and carbs, fruits and veggies, experts say.
So how do they all work together?
Before a workout, it's all about the carbs, said Carol Kelly, a dietitian at Emory University in Atlanta, Georgia. "Carbohydrate is the fuel for our bodies, fuel for our brains. If you think of your metabolism as a fire, carbohydrate is the fuel that helps the fire burn hot."
You want a meal that includes quality carbohydrates, lean protein, heart-healthy fats and fluids. Without a sufficient carb supply, you could be breaking down muscle when you exercise.
If you're working out in the afternoon or after work, you want to make sure to eat a balanced lunch with some carbs. Here are a few options:
--A turkey sandwich with a piece of fruit
--Whole grain pasta with low-fat tomato sauce
--A salad with grilled chicken
Now, if you're working out first thing in the morning for an hour or less, breakfast can wait until after your workout. That's because the body usually stores enough glycogen (the body's long-term energy storage molecules) from the previous night's dinner to fuel the workout.
After exercise, refueling (a.k.a. breakfast) needs to happen within 30 to 40 minutes. That meal should look like a combination of carbohydrates and protein, but not too much protein: 10 to 20 grams, or a palm-sized piece of chicken, is enough.
--You can try some of these combinations:
--Greek yogurt and an apple
--Hummus and whole grain crackers
--Grilled chicken and a baked potato
"With exercise, our bodies are constantly breaking down and need to be repaired and protein helps do that," Kelly said.
But there are still "free radicals" floating around in our bodies after we work out, one of the few negative effects of exercise. These are molecules which are produced when the body breaks down cells and can cause cell damage. The best solution to rid our bodies of free radicals is to eat lots of fruit and vegetables which help mop up damage that occurs during exercise. A salad, a piece of fruit, mushrooms, onions, even salsa --- all are good plant options to fit in throughout the day, according to Kelly.
If you do work out more than 60 minutes each day, you're going to have to up your carb and protein intake. And definitely don't delay breakfast if you're working out that long first thing in the morning. You're going to need some fuel to keep you going, whether it's some yogurt and toast or cereal with milk.
You can also sip on a sports drink while you work out. Some sports beverages get a bad rap for the sugar some of them contain, but for intense workouts that last longer than an hour, they do the trick. Stick to drinks that have a 6-to-8% solution of carbohydrates and electrolytes to help you hit your workout goal.
For those of us who aren't competing in a triathlon just yet, plain old H2O has everything you need to stay hydrated during your workout --and during the day.
The important thing is to get moving first and then work your diet around your exercise routine.
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