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Should you eat before or after your workout? A dietician weighs in

What to eat to fuel your workouts and feel your best.

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In the age of intermittent fasting, diet trends, keto and more, nutrition information can get confusing really fast. And that makes it even more challenging to decide what to eat before a workout. Should it be a keto low-carb snack? Or maybe a high-protein paleo one? No matter what nutrition philosophy you subscribe to, you want to eat something that will fuel you through your workout session to give you energy and help you reach your fitness goals. 

So how do you know what's best for you? I turned to an expert that knows a thing or two about fueling for performance: Rasa Troup, a former Olympian turned dietician who specializes in sports and performance nutrition. Even if you're not an athlete, the tips and scientific findings below will help you better understand how to fuel and recover from your workouts with food. 

Should you eat before a workout?

Eating before a workout is unappetizing some people, while others rather have food in their system to help them power through a workout session. But even though what (or if) you eat before a workout depends on the person, there are some key guidelines everyone should keep in mind when it comes to deciding if you should eat or not.

First, if you work out really early in the morning, chances are you may not even have time to think about food, let alone prepare something before you head out the door. But exercising on an empty stomach may not be doing you any favors. 

According to Troup, the science on fasted workouts is inconclusive, and she doesn't necessarily recommend it to her clients. According to her experience with clients, they aren't able to work out as intensely then if they have some fuel first. She says that shorter or less intense workouts won't give you much of an "after-burn" effect, which helps your body burn more fat even after you're done exercising.

Nevertheless, Troup says that some people choose to workout on an empty stomach because there is some evidence that it helps your body burn about 20 percent more fat during the workout. But while that sounds promising, Troup says that if you find that fasted workouts make you feel bad or are harder for you to recover from, it's not worth that potentially higher fat-burning benefit.

The best things to eat before your workout

What to eat before a workout

Greek yogurt and fruit is one example of a pre-workout snack that is a source of protein and carbs. 

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Fueling your workout isn't an exact science. Although there are some foods known to give you more energy and support your muscles (e.g., protein and carbs), you want to choose foods that you know are easy for you to digest and don't cause stomach issues (unless you like to stop mid-workout for a bathroom break... said no one ever).

Protein and carbs are your go-to nutrients when it comes to fueling workouts because carbs give your muscles energy, and protein helps your muscles repair faster. The best way to fuel a workout is with a protein- and carb-rich meal that you eat about three to four hours before a workout, according to Troup.

If it's been a while since your last meal and you want to boost your energy with a snack before a workout, try to time it about one to two hours before you exercise. That snack should contain easy-to-digest carbs like grains, fruits or veggies, and protein from sources like dairy, meat or protein powder (like collagen peptides or whey protein isolate). Troup offered a banana with peanut butter or greek yogurt with some fruit as examples.

Foods to avoid pre-workout

What to eat before a workout

The fiber in broccoli makes it harder to digest, which means you may want to avoid it before a workout. 

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One thing that's really good for your health, but not for your workout? Fiber. "Try to avoid bulky, fibrous foods that can sit in your stomach (like broccoli, cruciferous veggies, or beans). You want to have some foods that don't weigh you down [by sitting] in the stomach so the blood flow goes into your stomach -- you want the blood flow to go into your muscle tissue," Troup said.

The same goes for high-fat foods (even those of the healthy variety) since fat takes longer to digest, which means your stomach will compromise blood flow that you want to go to your muscles to aid your workout performance.

Is timing important? 

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The "30-minute" rule is the idea that drinking protein within 30 minutes of a workout is best for muscle repair and recovery.

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If you've ever seen someone down a protein shake as they leave the gym, then they probably subscribe to the popular "30-minute rule," which many think is the ideal window of time to consume protein after working out. But is it that important to pound protein immediately after a workout? 

According to Troup, there is science behind this timing window (she has her pro-athlete clients consume 25 grams of protein 15-30 minutes after training) but for the average person who's not a professional athlete or training for an endurance marathon or triathlon, it's not as crucial. "Most of us have 24 hours to recover from session to session, so that particular 30-minute window is not as crucial," Troup said. 

Not that protein isn't important after your workout -- it definitely is. But Troup says it's more beneficial to make sure you're getting enough protein through balanced meals throughout the day than worrying about hitting the 30-minute window. This is because consuming adequate protein throughout the day can help encourage muscle repair and promote good muscle composition. Troup recommends 20-50 grams of protein per meal (depending on your height, muscle mass and weight). 

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What to you eat after a workout

Your post-workout meals should look similar to a pre-workout meal: heavy on veggies and fruits, and include healthy proteins and fat. As Troup mentioned before, protein is highly important for muscle repair, so consuming it after a workout will encourage the recovery process. And consuming carbs is important too, since you just likely depleted them from your energy stores during your workout. 

"You need both protein and carbs to repair the damage on the muscle," Troup says. 

How supplements can help

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Supplementing with a protein powder can be helpful when you're short on time and need quick fuel.

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Although Troup has a "food first" approach when it comes to nutrition, she notes that supplements can be a helpful tool. In particular, collagen peptides, nitrates (derived from beets) and whey protein.

Consuming collagen peptides before a workout, like adding them to your coffee, can be particularly helpful since they provide protein that aids in muscle development. Collagen can also help with injury prevention during a workout. Nitrates (found in beets) are shown to improve performance and endurance, but there's no need to chug tons of beet juice since supplements or concentrated shots can help you get nitrates more efficiently.

Troup also recommends whey protein in a pinch, since milk is helpful for muscle growth. "We also know that milk seems to be the biggest stimulator of muscle protein synthesis, so consuming chocolate milk or whey protein isolate could be a good way of enhancing muscle protein," Troup said.


The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives. 

The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.