We've all been there—either you eat too much before a workout and feel sick and sluggish, or you don't eat enough and you feel lightheaded and dizzy.
The saying "Food is fuel" shouldn't be taken lightly, and pre-exercise nutrition is key. Here's the proper amount of time to wait between eating and exercising—plus, the best foods to nourish your body before a workout.
Why you shouldn't exercise right after eating.
When exercising, the blood flow is diverted away from the digestive tract, functional medicine physician Leah Johansen, M.D., tells mindbodygreen.
This is known as splanchnic blood flow, and it's the reason people should avoid exercising with a large volume of food in the stomach. Here are some uncomfortable side effects that can happen when you do:
- Stomach cramps
- Digestive upset
- Poor exercise performance
How long should you wait to work out after eating?
Overall, the amount of time you should wait between eating and working out will vary based on what you ate, how much you ate, and what type of workout you plan to do. But generally speaking, you should wait at least one hour after a meal and 30 minutes after a snack before working out.
"Meals should be consumed one to four hours prior to your workout, while snacks can be incorporated anywhere from 30 minutes to one hour before exercising," registered dietitian Maggie Michalczyk, R.D., tells mindbodygreen.
Those who are prone to cramping but want to get a bit of pre-workout nutrition can consider consuming a protein powder.
Certain endurance exercises (or those that last longer than 60 minutes) may actually require fuel during the workout too. If that's the case, Michalczyk says to add about 30 to 60 grams of easily digestible carbohydrates every 15 to 20 minutes. This will help sustain energy levels during a long-distance run or bike ride, she explains.
Keep in mind: People with diabetes have delayed gastric emptying, Johansen says, so they may need to wait even longer before exercising.
What to eat before a workout.
If you're lacking inspiration, though, these nutrient-rich options should supply you with plenty of energy before each workout. Remember to drink plenty of water before working out, too.
Before a run:
Aim to eat a meal 3-4 hours before a run, and include a combination of carbs and complete protein. In terms of snacks, Michalczyk suggests a bit of fruit within an hour of any run.
For long-distance runs (more than one hour), she says to stick to easily digestible carbs like bananas, energy gels, or a bite of a granola bar every 20 minutes.
Before a yoga class:
"Bursts of high-intensity exercise will deplete your energy stores pretty quickly," Michalczyk explains. "For this reason, your pre-workout choices should be pretty substantial. Oatmeal with nut butter and berries, lean chicken and brown rice, or eggs with whole wheat toast are a few great options."
Before all exercises:
Before any exercise, you'll want to make sure you're hydrated. Proper hydration can help prevent exertion headaches and other injuries. "A good baseline hydration level is to take your weight in pounds divided by two," Johansen suggests. "This is the amount of fluid, in ounces, that your body generally requires."
What to avoid before a workout.
While cruciferous veggies and big green salads are (rightfully) regarded as healthy foods, that doesn't mean they're best before a workout.
"If eating before a workout, avoid foods that take longer to digest such as high-fiber raw vegetables and big salads," Jaime Schehr, N.D., R.D., previously told mbg. "It's also best to avoid high-fat foods, especially greasy fats. Anyone who needs to eat before a workout will do better if the foods aren't high-fat or high-fiber."
What about fasted workouts?
These types of workouts generally take place in the mornings, if someone heads to the gym or goes for a run before getting breakfast in. They can also occur later in the day, though, so long as the most recent meal has been fully digested.
"Research shows it may take three to four hours for digestible solids to leave the stomach," Johansen says. In other words, if your goal is to work out on an empty stomach, it's best to wait at least three hours following a meal.
When and what someone decides to eat before a workout differs from person to person and depends on a variety of factors. However, most people will want to eat a protein- and carb-packed meal or snack at least 30 minutes to one hour before exercising. And once you finish your workout, here's exactly how to refuel.
Abby Moore is an editorial operations manager at mindbodygreen. She earned a B.A. in Journalism from The University of Texas at Austin and has previously written for Tribeza magazine. She has covered topics ranging from regenerative agriculture to celebrity entrepreneurship. Moore worked on the copywriting and marketing team at Siete Family Foods before moving to New York.