Pre Workout on Empty Stomach: can you take on an empty stomach?

January 8, 2024 |

Posted By

Max Health Living is a reader-supported site. Purchases made through links may earn a commission. Learn more.

Tough question:

Can You take pre-workout on an empty stomach?

Short answer: You can take pre-workout on an empty stomach. However, you may want to experiment with different timing to see what works best for you. It could also depend on the pre-workout supplement. Some are designed to be taken on an empty stomach for maximum absorption, while others recommend eating a small meal about an hour before taking the supplement.

You’re at the gym, you’ve just finished your warm-up and you’re ready to start your workout.

You reach for your pre-workout powder, but then you remember that you haven’t had anything to eat since breakfast.

Do you take it on an empty stomach or wait until you’ve eaten something?

In this article, I’ll discuss if it’s safe to take a pre-workout on an empty stomach.

Even though pre-workouts are generally considered safe for consumption on an empty stomach, they are not universally accepted to be harmless.

Each of us is built differently, and we may not show a generalized response to the processed pre-workout powders, which is why the reactions of our intricate and unique systems to pre-workouts consumed on an empty stomach may vary.

Some users have reported side effects like nausea, indigestion, or dehydration.

For this article, I have researched why most pre-workouts are standardized to be consumed unfed and what side effects users have observed from this practice.

So, keep reading to find out if taking pre-workout on an empty stomach is a safe practice or not.

Is it safe to take pre-workout on an empty stomach?

Yes, it is safe to take pre-workouts on an empty stomach.

In fact, some pre-workouts are designed to be fed on an empty stomach.

The reason behind it is that most nutrients are absorbed into the body from the gut.

And consuming pre-workouts in a tummy, not stuffed already with a lot of food, will aid the stimulants to better absorb in the blood, and thus, their benefits during the workout may kick in much sooner.

Another reason to take pre-workouts unfed is that it will expedite fat burning and help you get rid of that blubber faster.

The science behind this is that when you work out on an empty stomach, your body will use your fat stores for energy, thus helping you lose fat more efficiently.

The food you eat takes approximately six to eight hours to leave your stomach and move into the intestines.

And this fact may help you decide on the time interval you need to keep between your last meal and pre-workouts for the effects to hit you sooner.

Taking pre-workouts after a snack doesn’t mean that it will be ineffective.

But instead, you will require an additional 15 to 30 or maybe even 40 minutes for the pre-workout to take effect.

Moreover, according to this research, training after an overnight fast may improve the outcomes of the exercise on the skeletal muscles and metabolism.

But since gyming may take a great toll on your energy levels and nutrients, pre-workouts may help you endure fasting state exercise to avail its optimum benefits as they are made to provide you with the necessary energy and nutrients.

Although pre-workouts mostly do not bother users when consumed in a well-hydrated state, we can not rule out the possibility of side effects.

And this is why I searched all over the internet and looked for what the Reddit anecdotal reports are saying so that you know what undesirable effects may come with consuming pre-workouts unfed.

Head over to the next section to know what these side effects are.

Pre-workout on empty stomach side effects

On the one hand, you can turn to pre-workouts to prevent dizziness and weakness from working out in a fasting state.

On the other, drinking these pre-workout supplements on an empty stomach may also bring about some undesirable outcomes.

The contributors could be certain ingredients or other reasons that you need to be careful about.

Here are the few side effects of taking pre-workout supplements 0n an empty stomach:


Many Reddit users have reported feeling sick and nauseous on consuming pre-workouts on an empty stomach. You can find what the users are saying in this thread.

Although the exact reason has not been traced out yet, it may be due to the excess liquid you took in on an empty stomach.

You can try snacking on a half banana, a spoonful of peanut butter, a bowl of salad, or a sandwich, and try cutting down the pre-workout scoops you usually use to see if it helps.

Gastric distress

While I was looking through some Reddit stories, I found many users complaining of some stomach issues linked to pre-workout consumption.

Thus, there may be something in the pre-workouts that doesn’t favor the stomach.

Since the actual purpose of taking pre-workouts on an empty stomach is to promote better absorption of the stimulants and nutrients in it, some low-quality pre-workouts may also contain other synthetic ingredients like artificial flavors and anti-caking agents that may find their way through the gut into your body and cause digestive issues.

Caffeine may be another ingredient that may cause an upset stomach, and this meta-analysis can back this suspicion as it discusses the laxative effect of caffeine.

Other components that may cause cramping or other symptoms of gastric distress may be creatinine monohydrate, niacin, or artificial sugars.

In this thread, you can find users talking about the gastric issues they faced with pre-workout consumption.

Since pre-workouts have the potential to upset your stomach, taking it on an empty stomach may make these effects more pronounced.


Pre-workouts are based on certain ingredients that may lower their pH to about 2.75-2.95 or even less, which may cause acidity.

Ingredients that contribute to the acidic pH of pre-workouts may be sugar, caffeine, citrulline, citric acid, or bitter orange.

And this is why pre-workouts may cause acid reflux, especially when consumed on an empty stomach.

You might already know that caffeine is the primary stimulant in most pre-workouts. But some manufacturers go too overboard with the caffeine content, and some pre-workouts may have more than 350 mg of caffeine.

And while caffeine has the potential to make you jittery and cause energy crashes when consumed in excess during a typical day, it might wreak havoc when consumed in such large quantities on an empty stomach.

The stimulating effect of caffeine may kick in much sooner when consumed in a fasted state because it will enter the bloodstream more quickly in this case.

In this research, you may find how the bitter taste of caffeine stimulates the increased production of gastric acid, which may cause acidity.

Another ingredient, sodium bicarbonate, might also contribute to acid reflux.

You may find users talking about indigestion caused by pre-workouts in this thread.

To counter this side effect, you may opt for low caffeine pre-workouts with a caffeine content ranging between 200 and 250 mg or go for low stim variants.

Drinking ample amounts of water before and after your pre-workout may also help.

Wrap Up

To sum it up, taking pre-workout on an empty tummy is generally considered safe, but it may not be well suited for every single user.

You can look for organic, low caffeine, or low stim pre-workouts because they may somewhat prevent the detrimental effects of taking pre-workout supplements in a non-fed state.

Taking pre-workouts on an empty stomach seems perfect to augment your performance during a light exercise such as jogging or cycling.

But for high-intensity exercises, like weight training, which requires a lot of stamina and energy, only one glass of pre-workout may not be enough to make you last.

Nonetheless, lifting weights with a stuffed belly is not a great option, as it might make you a tad queasy.

So, you should talk to your trainer to get a final verdict on whether taking pre-workout before or after a meal would do good for you, as it depends on the type of workout training you are pursuing.

FAQs on pre-workout on empty stomach

Do you need to eat before taking a pre-workout?

From the discussion above – you’ll see that there is no right or wrong answer to this question, as everyone’s body will respond differently.

Some people feel they need to eat something before taking a pre-workout supplement, while others find that they have more energy and perform better when they don’t have anything in their stomach.

The bottom line is that you should listen to your body and experiment until you figure out what works best for you. If you find that you’re not performing as well as you’d like or feel sluggish during your workouts, try eating a light snack about an hour before taking your pre-workout supplement.

But if you feel fine without eating anything, then there’s no need to change what’s working for you.

Can pre-workout damage your stomach?

It depends on the composition of the supplements and how your body reacts to workout drinks. So yes, pre-workout supplements could cause stomach problems if you’re not careful.

Many of them contain high levels of caffeine and other stimulants, which can lead to nausea, vomiting, diarrhea, abdominal pain. In some cases, the ingredients in these supplements can also be hard on your stomach lining and cause gastritis or even ulcers. So if you’re planning to start taking pre-workout supplements, it’s important to do your research first and find one that’s gentle enough on your stomach.

Important Disclaimer: The information contained on MAX HEALTH LIVING is intended for informational and educational purposes only. Any statements made on this website have not been evaluated by the FDA and any information or products discussed are not intended to diagnose, cure, treat, or prevent any disease or illness. Please consult a healthcare practitioner before making changes to your diet or taking supplements that may interfere with medications.

Who We Are

We are a team of fitness, health, and supplement experts, and content creators. Over the past 4 years, we have spent over 123,000 hours researching food supplements, meal shakes, weight loss, and healthy living. Our aim is to educate people about their effects, benefits, and how to achieve a maximum healthy lifestyle. Read more.