I regularly exercise with a friend in the early morning. Before we meet in the dark, I chug a bit of green tea while she fits in two slices of whole grain toast with peanut butter. Is one of us better prepared for that workout?

When I studied how the body uses nutrients to fuel its many endeavors, I learned that timing food consumption with exercise is important to consider whether you are striving for peak performance, efficient tissue repair or just better overall health. I also learned that each body is different and that staying in tune with our own signals is one of the healthiest things we can do.

So, should I listen to science, which tells me to eat protein, carbohydrates and a little fat at least 90 minutes before my run? Or should I listen to my body, which tells me to sleep a little later, enjoy my tea and eat something afterward?

To dig deeper into the science behind what and when to eat to fuel exercise, I spoke with two experts. Barbara Lewin is an internationally recognized sports nutritionist who has been teaching athletes to improve their health and optimize performance for more than 30 years. J Braun is a strength trainer to individuals and D.C.-area sports teams and the owner of the Northwest-based Tidal Elite Performance Center.

Braun explained that “food is just energy, so when you decide what to eat before a workout you want something that gives your body the most usable energy.” Usable is the key word, because many foods that provide caloric energy to the body deplete energy during digestion. Dairy is an example; many people struggle to digest the casein protein in dairy and find themselves sleepy or bloated after eating it. Those aren’t ideal sensations before a workout.

Lewin suggests limiting fiber and fat before exercising because they “take longer to digest and a full stomach can inhibit a workout. Also, if the pre-workout food is not digested, the energy from that food is not getting to the muscles.”

If you can better time your meals for performance than I can early in the morning, Lewin explains that the ideal time to eat is one or two hours before a workout, so the body has time to digest the food and use the nutrients.

Braun says his “favorite pre-workout snack is an apple with nut butter because it provides natural glucose, protein and healthy fats. The old advice to eat a bagel, pasta or bowls of cereal before a workout is flawed. It is better to eat regular meals with the right balance of protein, healthy fats and natural carbohydrates and then add in digestible pre- or post-workout snacks such as that apple, a cup of soup or a smoothie, if needed.”

These are the food groups that best fuel a workout:

•Carbohydrates make energy in the body faster than any other foods and are the primary place the body goes to find energy. Eat fruits, vegetables, and whole grains such as brown rice, oatmeal and quinoa.

•Protein, a longer-range source of energy, helps build and repair muscle and tissue, and it regulates muscle contraction and water in the body. Don’t fall for the myth that you need to eat tons of protein to build muscle; stick to no more than 15 percent of total calorie intake. Get it from eggs, lean meats, fish, beans, nuts and seeds.

•Fats are also a secondary source of energy. Nuts and seeds, fish, meat, and olive oil provide energy and build the brain, supporting quick thinking on the sports field or during that fast-paced Orange Theory class.

•Water supports all bodily functions. Studies show that athletic performance can be affected by what, how much and when an athlete drinks. Braun recommends sips throughout the day and during a workout rather than gulps afterward. Stopping to take a few sips every now and then also gives the athlete time to catch their breath and gear up for the next segment of the workout.

I asked both experts about their ideal post-workout snack. Lewin says a recovery snack is often only beneficial if someone has worked out for more than an hour. For her athletes, she likes to whip up a fruit and protein-fortified nut milk smoothie with a 4-to-1 ­carbohydrate-to-protein ratio to be consumed 20 to 30 minutes after big workouts for optimal glycogen replacement. She likes a liquid recovery snack such as a smoothie because it also rehydrates.

When I spoke with Braun, he was mixing up his own version: whey protein, nut butter, almond milk, MCT oil and cold brew. Both he and Lewin are fans of a little caffeine before a workout for people whose bodies tolerate it, but neither would recommend it for kids or recommend drinking too much of it.

Neither Lewin, Braun nor I subscribe to the idea that chocolate milk is the ideal recovery snack. Although it offers the right muscle recovery ratio of protein to carbohydrates, drinking chocolate milk with its difficult-to-digest casein and high amounts of sugar has its own side effects, especially for people with diabetes or blood-sugar issues. “Eating the right amount of protein for your body throughout the day is the best way to give your muscles the nutrients to repair and grow,” Braun says. Lewin agrees that “an athlete’s whole diet needs to reflect the nutrients they need, not just the recovery snack. I don’t want to see a lot of simple sugars in people’s diets throughout their day, as sugar is inflammatory and addictive.”

Lewin ended our conversation by saying that “although some science is universal, people are so unique.” I concur. When we eat because we think we are supposed to eat rather than when our body tells us we are hungry or need replenishment, we lose the authentic connection to our bodies. Listening to our bodies, which will most often tell us what we need, is always the best strategy.

That’s why I am content to run on a stomach of green tea while my running partner is equally as justified in eating her toast right before we head out the door. Perhaps neither of us are doing it scientifically right, but we both know what feels right to us.

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