Skip to Content

Can You Take Pre Workout On An Empty Stomach?

If you’re anything like me, you like to get the best results out of everything you do.

Whether that’s in a high school essay, a project at work, or even from the supplements you take.

Now, if you want to get the best results from supplements, there are many things to consider. Such as:

  • The dose you take.
  • The time of day that you take them.
  • Whether or not you take them on an empty stomach.

In this article, our focus is on pre workout, and whether or not it’s best to take it on an empty stomach.

Can You Take Pre Workout On An Empty Stomach?

Taking pre workout on an empty stomach can deliver more benefits, such as increased fat loss and faster absorption. However, by taking pre workout on an empty stomach, you’re more likely to experience side effects.

In this article, we discuss the benefits and drawbacks of taking pre workout on an empty stomach, as well as whether you should work out on an empty stomach. Let’s get to it.

Benefits Of Taking Pre Workout On An Empty Stomach

Improved Fat Loss

Many pre workout supplements have various ingredients that help with fat loss, such as caffeine, green tea extract and L-carnitine. Out of these ingredients, caffeine is by far the most common.

While most pre workouts contain caffeine in the 100mg to 300mg range, some contain a whopping 400mg per serving.

(To give you some perspective, the average cup of coffee contains around 100mg. So yes, some pre workouts have 4x as much caffeine as a cup of Joe!)

Well, a review of 12 studies found that every doubling of caffeine intake increased fat loss by 28%!

But there’s a caveat…

When you take pre workout when in a fed state (i.e., with food), your insulin levels will be higher, since food spikes insulin.

Unfortunately for fat loss, insulin is a storage hormone that instructs your body to store energy rather than to burn it.

So, by taking pre workout on an empty stomach, your body will already be in a fat burning state and caffeine will add fuel to the fire.

Faster Results

Taking pre workout on an empty stomach should result in you feeling the effects quicker.


Well, when you have an empty stomach, there’s no food to digest which means the pre workout is prioritised and can enter your bloodstream quicker.

As a result, you should feel the pre workout buzz that we all know and love much sooner.

If you do take it with food, I’d ensure you wait an hour before working out to give your body time to digest it.

(There’s nothing worse than it kicking in as you’re walking home from the gym!)

Better Utilization of BCAAs

Many pre workouts out there contain BCAAs.

And for good reason too – they’re cheap, effective, and help with recovery.

But when you take BCAAs alongside food, you encounter a bit of a problem.

You see, protein in food is just amino acids that are bound together.

When you eat food, your body uses a lot of energy breaking this protein down into amino acids, so your body can use them.

So, if you take BCAAs with food, then there’s going to be a load of other amino acids that are competing for absorption.

In another words, the BCAAs may not be available to your muscles until the other amino acids have been utilized.

This can be problematic if you’re working out just after a meal, as the BCAAs won’t be usable during the workout.

So, by taking pre workout on an empty stomach, the BCAAs will be able to fully support your workout as intended.

Drawbacks Of Taking Pre Workout On An Empty Stomach

False Sense Of Energy

Pre workout is notorious for making you feel like you can take on the world.

Normally, this is exactly what you want right before your workout.

But, if you get this feeling when you have no food in your system, you could push yourself harder than your body has the energy for.

Think about it…

If you just woke up and felt super hungry, the last thing you’d want to do would be to try and beat your squatting PB.

(You subconsciously know this would be a bad idea, as your body just wouldn’t have the energy for it.)

Whereas if you just woke up and took pre workout, you’d be more than willing to get your gym shoes on and dive into the squat rack.

If you’re attempting a weight that your body doesn’t have the energy for, this could actually be dangerous.

Additional Side Effects

Since taking pre workout on an empty stomach speeds up absorption, it could mean that you feel the effects of certain ingredients like caffeine more intensely.

Now, I don’t know about you, but when I consume too much caffeine, I feel anxious, jittery & irritable.

The last thing I’d want before benching 200lb would be to feel anxious that I couldn’t do it!

Also, some people have reported suffering from anger, stomach pain, and nausea after taking pre workout on an empty stomach.

Although this is purely anecdotal, it’s still worth noting.

Can You Take C4 Pre Workout On An Empty Stomach?

As the best-selling pre workout in America, I’m sure many of you are wondering whether you can take C4 on an empty stomach.

And the answer is yes.

Whether or not you’ll see better results is a different question, and the only way to find out is to give it a try.

Can You Take Pre Workout While Intermittent Fasting?

You can take pre workout while intermittent fasting, but only if it contains no sugar or artificial sweeteners.


Well, sugar and artificial sweeteners trigger an insulin response, which is what people want to avoid when fasting.


Wrapping things up, there’s no right or wrong answer to the question:

Should You Take Pre Workout On An Empty Stomach?

It all comes down to individual preference, and what you value the most.

Those who value fat loss would benefit from taking pre workout on an empty stomach.

Whereas those who want to minimize side effects wouldn’t.

That’s all for this article, but you may be wondering how long to cycle off pre workout? Or can you put ice in pre workout?

Hope this helped!