The Best (& Worst) Foods To Eat Before A Workout, From Sports Dietitians

As any athlete will tell you, proper nutrition can help you get the most out of your workouts. What you eat in the few hours leading up to your exercise sessions can make a difference in your performance and impact your post-workout recovery. 

Your body needs adequate fuel and hydration to support physical activity. What you eat before a workout will depend on the exercise you’ll be doing and how much time you have before your workout. One thing’s for sure, though; carbohydrates are king when fueling most types of exercise. 

“For the majority of individuals, it makes sense to emphasize carbohydrates in a pre-workout meal or snack,” says performance dietitian and consultant, Kelly Jones MS, RD, CSSD. “This is because carbohydrates are the preferred and most efficient source of energy for exercising muscles when moving at moderate to high intensities and are important for extending the duration of workouts for moderate endurance training.” 

Our bodies store carbohydrates as glycogen in the muscle. Jones says consuming carbohydrates before exercise allows us to top off those stores and maintain blood sugar levels during activity. 

Moderate amounts of protein can also be beneficial before resistance exercise. A few studies have shown that a combination of carbohydrates and protein1 taken before activity can reduce the markers of muscle damage throughout the first 24 hours of recovery. 

“As a general rule of thumb, we always prioritize carbohydrates, fluids, and protein in our pre-workout foods and drinks while keeping fiber and fat on the lower side,” says Briana Butler, MCN, RDN, LD Co-Owner of Stef and Bri Wellness. “While the carbohydrate can top off glycogen stores and provide long-lasting energy needed for training, the protein can deliver amino acids that kick-start muscle growth.”

Resistance training is key to muscle growth. Because strength training workouts don’t generally lead to significant carbohydrate depletion to the point where performance is impaired, Spano says you don’t necessarily need to eat beforehand.

However, if you haven’t eaten in over three hours, she says consuming some protein beforehand is a wise idea to maximize muscle building (and you'll definitely want to eat some protein after you wrap up resistance training).

“For those trying to lose weight, it’s important to remember that it’s still okay to nourish your body pre-workout,” says Butler. “Increasing protein and lowering carbs may be helpful depending on the type of workout, especially if the activity requires minimal intensity.”

“I find many people who are seeking weight loss or are frustrated with weight gain tend to actually be eating too little earlier in the day or before exercise,” says Jones. “I wouldn’t recommend anything different to these individuals than I’d recommend to anyone else!” 

When it comes to choosing pre-workout foods, the possibilities are endless. What works for one person might not work for another, even before the same types of exercise. The dietitians we spoke with all like to eat different things before their workouts, but they all agree on choosing foods that are higher in carbohydrates and low in fiber and fat.

No matter what type of exercise you’ll be doing, staying well-hydrated before your workout is also essential. 

“Consuming water and electrolytes before you workout will help expand your blood volume to ensure you have optimal blood flow to working muscles,” says sports dietitian and author Marie Spano, M.S., R.D., CSCS, CSSD. “Fluid and electrolytes also help decrease fatigue and risk of muscle cramping.” 

The American College of Sports Medicine2 recommends slowly drinking 5 to 7 milliliters of hydrating beverages per kilogram of body weight at least four hours before exercise. This comes out to around 14 oz—a little less than two glasses—of water for a 150-pound person.

Jones also suggests drinking a glass of water with your pre-workout meal to aid in digestion and absorption of nutrients while also helping reduce the dehydrating effects of exercise. 

The size and portions of your pre-workout meal or snack are based on timing, your gut tolerance, your activity type, and what else you have eaten. 

“The closer to a workout you are eating, the less protein, fat, and fiber you may want to consume in order to prevent feelings of over-fullness and ensure efficient digestion and absorption of energy eaten from carbohydrates,” explains Jones. “The further from the start of a workout you are eating, the more fiber, fat, and protein you may want to include in order to more slowly release energy into the blood and to prevent feelings of hunger right before and during exercise.” 

Pre-workout nutrition involves trial and error to determine what food combinations, portion sizes, and timing work best for you for different types of exercise and duration. 

Fueling appropriately before training is important to prevent low blood sugar (which can cause fatigue and dizziness), fuel performance, top off your fuel tank, preserve muscle mass, and speed up recovery. 

The intensity and duration of your training session will influence the energy your body needs and what you should eat beforehand to be adequately fueled. 

“For example, higher-intensity workouts require more carbohydrates because we tend to burn through our energy stores quicker,” explains Butler. “While lower intensity workouts are not as taxing and can be fueled with a more balanced meal.”  

Since running is a high-impact activity, you’ll want to leave plenty of time to digest your food and stick to low-fat and low-fiber snacks the closer you get to the start of your run. 

“For longer workouts, I’d work on increasing the pre-workout fueling to at least 60-80 grams of carbs before the workout,” says Larson.

This can come from a combination of easy-to-digest carbohydrates such as gels, bread, lower-fiber fruit, or low fiber cereal, says Spano. “If your running pace will be fairly slow, you may be able to tolerate forms of carbohydrate with a little fiber in them such as granola bars," she adds.

What you eat before a HIIT workout will depend on how long the workout is and when you last ate. 

“If you are doing a shorter workout or if you’ve eaten the past few hours, you do not necessarily need to eat anything beforehand,” says Spano. “If you haven’t eaten in a few hours or you have a longer workout ahead of you, consume 1 g of carbohydrate per kg of body weight.” This will come out to about 68 grams for a 150-pound person.

If you participate in a sport, whether team or individual, you may also need meal timing strategies. The type of sport, intensity, duration, and when you last ate will influence your pre-game or pre-match snack choice.

“Sports like tennis and hockey are high-intensity and involve a lot of stop-and-go,” says Jones. “This means both high energy expenditure and a lot of movement that requires more easily digestible foods. Recommendations similar to pre-running will work.” 

Jones adds that for sports like softball, baseball, or golf, less attention needs to be paid to reducing protein, fat, and fiber unless you’re in the position of a catcher or pitcher, where digestion can be impacted more.

There are several reasons why someone may want or need to skip eating before a workout. It may be okay depending on the type and duration of exercise you’ll be doing, and the motivation behind working out fasted. 

“It’s best to do fasted workouts only when they are shorter in duration, such as under 45 minutes, and easier in effort, heart rate zone 1 or 2,” says Larson. “Doing harder and/or longer workouts while fasted can be a struggle to complete them and will leave you feeling exhausted and low-energy afterward.”

But if you’re skipping your pre-workout meal or snack because you think it will lead to more fat loss, you may be doing yourself a disservice. By not fueling correctly, you likely won’t be able to work out as hard or as long, which means you’ll burn fewer calories during your workout. 

“Working out in a fasted state will not increase fat loss3 to a greater extent than working out in a fed state,” explains Spano. “More of the calories burned during your workout will come from fat versus carbohydrate compared to exercising in a fed state however, for body fat loss, what matters is total calories burned, not the fuel source used during a workout.”