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Pre Workout Crash (Why It Happens + How To Stop It For Good!)

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Pre workout is supposed to make you feel more alert, focused and energized.

But many people feel drained after taking it.

Here’s why pre workout can make you crash:

Pre workout can make you crash due to the high amounts of stimulants, like caffeine. When the pre workout rush has worn off, you’re likely to experience a caffeine crash which will make you feel tired and lethargic.

In this article, we cover why pre workout can cause tiredness, how to stop feeling tired after taking pre workout, whether all pre workouts cause tiredness, and much more!

3 Reasons Why Pre Workout Makes You Crash

Appetite Suppressant

Pre workout often contains a high amount of stimulants, like caffeine.

While these can help keep you focused and alert, they can also suppress your appetite.

Now, when you have less appetite, you’re likely to consume less calories over the course of the day.

The outcome of this is a lower energy intake, which can make you feel tired.

More Intense Workouts

Pre workout includes many ingredients which help improve the intensity of your workouts.

For example, creatine helps increase ATP, which is what your cells use to make energy.

So the more ATP your muscles have, the more reps you can squeeze out.

Another example is beta alanine, which helps reduce lactic acid build up.

Since lactic acid is responsible for the ‘burn’ you feel when working out, pre workout can help you milk out more reps by delaying that burning sensation.

By doing more reps, your muscles will be more fatigued which can lead to tiredness.

Another thing to consider is that you’ll burn more calories by doing more reps.

The more calories you burn, the more energy (food) you’ll need to consume to stay in a calorie surplus.

So if you’re not eating enough food, you may feel drained throughout the day.

Caffeine Crash

Many pre workouts contain a whopping 400mg of caffeine per serving.

(To give you some perspective, a cup of coffee contains “only” 100mg.)

While this super dose of caffeine will energize you to begin with, unfortunately what goes up must come down.

So once the caffeine has worn off, your energy levels can crash and you may feel the common side effects of pre workout like nausea, tiredness and irritability.

If you do feel tired after taking pre workout, it’s probably a sign that you’re taking too much caffeine.

This means your caffeine tolerance is too high.

(A great way to reset your caffeine tolerance is to cycle your pre workout.)

What Does A Pre Workout Crash Feel Like?

This ultimately depends on the ingredients of your pre workout and how much you’ve taken.

If you’re pre workout is high in caffeine (as most are), then you’ll feel irritable, lethargic and possibly even nauseous after it’s worn off.

If your pre workout has reduced your appetite, then you may start feeling hangry as your body is low energy and craving food.

Do All Pre Workouts Make You Crash?

In short, no.

Thankfully, you can buy stimulant-free pre workout which won’t kill your appetite or give you the dreaded caffeine crash.

One of my favorites is Genius Pre Workout Powder (Amazon).

It’s awesome as it’s naturally sweetened, includes nootropics, and is from a respectable brand that I love.

Can Too Much Pre Workout Make You Crash?

Ultimately, this depends on the pre workout.

If it’s your typical stimulant-heavy pre workout, then 100% yes.


Well, the more pre workout you take, the bigger the initial rush you’ll feel.

But unfortunately, the bigger the energy crash too!

Whereas if it’s a caffeine-free pre workout, then perhaps not.

Does Pre Workout Make You Crash The Next Day?

Yes, pre workout may make you feel tired the next day.

One reason is that if you take pre workout in the afternoon, the caffeine may disrupt your sleep which will make you feel groggy the next day.

Also, if you’ve pushed yourself harder in the gym thanks to pre workout, then your muscles may be more fatigued the next day.

And if pre workout has helped you burn more calories, you may wake up in a calorie deficit with low blood sugar levels, which can make you feel grouchy.

How To Stop Feeling Tired After Pre Workout

Now that you know why pre workout can cause tiredness, here are some top tips to reduce this annoying side effect.

Take A Stimulant-Free Pre Workout

Most of the tiredness felt after pre workout can be blamed on the stimulants, as these are responsible for suppressing your appetite and crashing your energy.

So to combat this, it makes sense to take a stimulant-free pre workout.

Take Less Pre Workout

You may be thinking: Well, I’ve already bought some pre workout, and it isn’t stimulant-free, so what can I do?

Well if that’s the case, then you can reduce tiredness by simply using less pre workout.

By doing so, you’ll experience a smaller stimulant-crash, as well as having more appetite.

Eat Plenty of Calories

The other cause of tiredness after taking pre workout is a low energy intake.

So to alleviate this, you just need to eat more food, as simple as it sounds!

While you may not have the appetite for it, the discomfort will be worth it when you have more energy during the day.

Avoid Consuming Additional Caffeine

Who loves a strong coffee first thing in the morning?

I certainly do.

But if you drink a strong coffee followed by taking pre workout, your caffeine levels will be even higher.

Unfortunately, this means you’ll suffer an even bigger energy crash!

So if you are planning on taking pre workout, you should replace your morning coffee with a caffeine-free herbal tea.

Should You Worry If You Crash After Taking Pre Workout?

Definitely not!

Worrying is a negative emotion which will drain your energy even more.

This can reduce the quality of your workout, which is the opposite goal of taking pre workout!

What Should You Do If You Feel Tired After Taking Pre Workout?

The tiredness kicks in after a few hours of taking pre workout, as this is when the caffeine crash starts to take place.

So it’s super important to work out within an hour of taking pre workout, so that you’re not attempting a deadlift PB mid caffeine crash!

But if you do feel tired after the gym, you should eat plenty of calories so that your muscles are refuelled and to give you energy for the rest of the day.

Can You Take Pre Workout At Night To Help You Sleep?

Some may be thinking: Well, if my pre workout is making me tired, should I take it before bed to help me sleep?

The answer to which is definitely not.

Taking pre workout at night is more likely to disrupt your sleep, as caffeine has been shown to disrupt sleep quality.

You might also find these articles interesting…


Creatine Increases ATP

Caffeine Side Effects


Monday 28th of February 2022

I came here looking for why preworkout makes me sleepy and got a list of common sense explanations of why one can be tired way after taking pre workout. I want to know why preworkout makes me sleepy like RIGHT after I take it. I literally drink it and within 10-15 minutes need to nap.


Friday 11th of March 2022

That's interesting Will. Is this with a specific brand? Perhaps you're sensitive to one of the ingredients.


Thursday 17th of February 2022

I am 15 and i drank my first preworkout, about 300mg of caffeine. After about 5 hours i felt for a milisecond like i was gonna fall, and i feel a litle chest pain and i am very tired. Should i still take preworkout?!


Friday 11th of March 2022

You should definitely check this with a medical doctor!