Nutrition / Pre & Post Workout

Are These 6 Foods Slowing Down Your Workout?

Don’t let your pre-workout meal affect your ability to exercise.

Nothing is worse than getting to the gym and feeling sluggish or plagued with bloating and stomach troubles—if you even make it there, that is. If you’re someone who regularly feels weighed down or low-energy when working out, you might want to take a look at what you’re eating right before exercising. There are certain pre-workout foods that can kill your energy levels. Avoiding these foods right before working out can help improve your performance.

“Fueling properly before a workout can make or break your session,” says Registered Dietitian Nutritionist Megan Casper, MS, RDN, CDN. “Although I usually recommend foods high in protein, fiber, and healthy fat, all three of these take longer to digest, making them not ideal for a pre-workout meal. Instead, give yourself a couple of hours before a meal containing these. Or, nosh on foods with simpler carbohydrates if you need a snack soon before.”

You certainly don’t need to avoid these foods altogether. However, it’s useful—and just interesting—to see how what you eat affects how energized you feel when you work out. If you’re not sure what could be hindering your workout, pay attention to these six pre-workout foods that could be slowing you down.

1. Dessert Foods

When it comes to pre-workout foods, avoid anything that qualifies as a dessert or is dessert-adjacent. Sugar gives a quick burst of energy followed by a crash, which isn’t ideal to sustain energy levels throughout a long workout. However, there is a difference between the natural sugar found in fruit and added sugar that you get in a candy bar when it comes to what will serve you best before exercising. “The natural sugar found in fruits, vegetables, and grains (aka carbs) are the primary fuel source for a workout,” says Registered Dietitian Natalie Rizzo, MS, RD. “These will not slow you down and will enhance your workout.”

2. High-Fat Foods

Avoiding heavy meals or anything too rich before a workout can help keep you energized, too. Of course, there are healthy fats that can benefit your diet (hello, avocado and nuts). However, eating a meal high in fat before a workout can slow you down. “Out of the three macronutrients (carbs, protein, and fat), fat takes the longest to digest,” says Rizzo. “That means [that] if you eat something really high in fat—think fried foods or bacon—right before a workout, it will sit undigested in your stomach and cause indigestion.”

3. Salty Foods

Sodium is important for fluid balance, as low sodium levels can dehydrate you and weaken the muscles. But, this doesn’t mean that you should load up on a big bowl of french fries before going on your run. Super salty foods can also lead to dehydration or bloating, which is not ideal when you’re trying to get moving. “If you’re working out in really hot or intense conditions, you may need some extra salt to replace that loss in sweat,” says Rizzo. “This one is determined by how intense the workout is.”

4. Dairy

Dairy tends to get a bad rep, but it’s not necessarily one of the most detrimental pre-workout foods. The impact of dairy on a workout varies across individuals, depending on if you have an intolerance or not. “If you tolerate dairy well, it’s perfectly fine to have some one to two hours before a workout,” says Rizzo. However, if you’re sensitive to dairy or if you eat too much of it, you might find yourself more sluggish during a workout. “Dairy products contain protein and fat. Both take longer to digest and can lead to indigestion and bloating if you work out soon after eating,” says Casper.

5. Raw Veggies

There’s usually no reason to avoid vegetables. They can provide the energy needed for a workout. But, you do want to be careful not to eat too many raw veggies that are full of fiber—like broccoli and cauliflower—immediately before a workout. They may give you gas, which will hinder your exercise. “Eating anything high in fiber, like raw veggies, takes longer to digest, potentially causing discomfort,” says Casper. “Fiber also grabs ahold of water, which can make you feel bloated and full.”

6. Spicy Foods

To avoid heartburn while exercising, steer clear of spicy foods too close to a workout. Spicy foods affect everyone differently, but they may slow you down if they give you indigestion, says Rizzo. If you’re going to chow down on some hot wings, give your body some time to move it along before hitting the gym. Some people are more intolerant to spicy foods than others and will feel the effects more greatly.

Paying attention to your pre-workout foods can help ensure that you have an optimal workout free of bloating, stomach troubles, and low energy. It’s true that these foods might not have any impact on all on some. So, keep track of how various foods affect your performance and make changes, as needed.

Nutrition Pre & Post Workout


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