Ask the Expert: What Are the Best Foods to Eat Pre- and Post-Workout?

Photo via iStockphoto.com/jacoblund

What to eat before and after a workout can be such a conundrum. Do you eat before your 6 a.m. spin class or wait until you get to work? What about workouts after work—do you eat dinner before 6 p.m. boxing? Or is that a recipe for an upset stomach? And protein shakes…are they necessary? The questions are endless. We’re all worried about optimizing performance, stimulating muscle growth, and at the bottom line, just making sure we’re not starving or getting sick mid-workout. To get to the bottom of what foods to eat pre- and post-workout, we chatted with certified personal trainer and registered dietitian Kelli Fierras to get her take.

Something to keep in mind before you dive in, though: All of these answers are dependent on many different factors, including age, gender, height, weight, etc., along with the activity being performed, the duration of the activity, and the intensity of the activity. If you have more specific needs or questions, please seek the guidance of a registered dietitian/nutritionist.

Ask the Expert: What Should I Eat Before and After I Workout?

The answer: It depends on the intensity and duration of your workout, but there are some general guidelines. 

The details: 

“Pre- and post-workout nutrition can be very specific, depending on the person and the specific activity being performed,” Fierras says. “And it can play a major role in one’s performance and health.” Generally speaking, she recommends eating about one to three hours before you exercise, depending on how your body tolerates food, of course, and to eat within 15 minutes of finishing your workout. This time window, she explains, helps your body to optimally rebuild muscle and replenish glycogen (the storage of carbs in your muscles for energy).

What to eat before you workout: 

For workouts less than 60-90 minutes, a carbohydrate snack is ideal, she says. You want something that empties from the stomach quickly and can be readily used by your body for energy. Think: a piece of fruit with one tablespoon of peanut butter, Greek yogurt with 1/4 cup of berries, or oatmeal with low fat milk. You want to steer clear of a lot of protein and fat right before you exercise, because these foods take longer to digest and will sit in your stomach longer, something you don’t want while you’re bouncing up and down in a high intensity bootcamp or spinning at Soul Cycle.

What to eat after you workout: 

Slamming protein shakes after you work out isn’t entirely necessary, so don’t think you have to go out and buy a tub of powder and a shaker bottle to consider yourself fit. Fierras says you should look for something high in carbohydrates and protein to repair and build muscle. Your body’s glycogen stores will be depleted after working out, meaning you’ll need more carbs to replenish those stores so you don’t feel completely fatigued. “You should aim to eat at least 10-20 grams of protein with a carbohydrate,”   she says. “This depends on your body size, though—larger people might need more and smaller people might need less. This snack could look like a low fat chocolate milk, hardboiled egg with an apple, or oatmeal and nuts.”

For early-risers: 

Early morning exercise can be tricky to navigate in terms of nutrition. It’s a little too early for breakfast, but if you didn’t eat enough the night before, you run the risk of low blood pressure and possibly fainting. Fierras says a carbohydrate snack is ideal, with a little bit of protein. This could be a rice cake with peanut butter, a protein ball made with oats, protein powder, peanut butter, and fruit (maybe try this recipe), or 1/2 a banana with peanut butter. If you can’t tolerate solid food that early in the morning, she says half of a smoothie or low-fat chocolate milk will suffice.

It’s best to gauge how you feel and what type of exercise you’re doing in the morning, though. “If you go to the gym and walk on the treadmill for 20 minutes and you don’t wake up hungry, you may be okay to wait until you’re done working out,” Fierras explains. And if you eat a large dinner the night before, your glycogen stores will be boosted, preventing low blood sugar the next morning, and you might not need that much food before you exercise.

For evening gym-goers: 

The most important thing to think about for folks who work out after work is eating something that will hold you over until dinner, without being too heavy in your stomach for a workout or ruining your appetite for dinner. Fierras recommends a smoothie made with low fat milk and fruit, lowfat chocolate milk, yogurt with berries, or a protein ball. 

The bottom line: 

Pre- and post-workout nutrition really doesn’t vary that much, and unless you’re a top-performing athlete, your choice won’t make or break your workout—unless you’re either 1.) getting sick from eating too much or 2.) passing out from eating too little. You want to aim for the middle ground and then be sure to replenish after your workout. Optimize your meals with fast-digesting carbs and refuel with a good source of protein afterwards. As with all things nutrition, we tend to make it more complicated than it needs to be.