We all know the benefits of pre-workout, but there are many different types to choose from, and it's challenging to know which is best.

Stimulant vs non-stimulant pre-workout is a hot topic in the fitness world, and there's a lot of debate about which one is better for you.

Well, we're here to help; in this article, you'll get all the information to help you make an informed choice.

People Who Work Out In The Morning

If you're working out in the morning, you'll benefit from some extra energy that comes from caffeine or other stimulants. This will help to fight your tiredness and help you get more from your training.

People Who Metabolize Caffeine Easily

Everyone's body produces enzymes that break down food and drink. If you are able to metabolize caffeine quickly, you're less likely to feel any side effects.

The half life of caffeine is typically about 5 hours, but if you have a fast metabolism, it can be gone in less than 3, so it won't impact your sleep schedule.

If Weight Loss & Fat Burning Is Your Fitness Goal

If your goal is to lose fat, then a stim pre-workout can be more effective. The caffeine can help to boost your metabolism, increase your heart rate, and ultimately help you burn more calories. This will lead to greater fat loss during your workouts.

man taking stim pre-workout

Who Should Take Non-Stim Pre-Workouts?

If You Prefer Working Out At Night/Evening Time

If you prefer working out after work in the evening, then you'll be better with a stimulant-free supplement.

Training without getting the right amount of sleep can impact protein synthesis in your body, so if you take a stimulant too late, it can ruin your sleep and impact your gains. Taking a stim-free pre-workout will let you work out late without impacting your routine. [3]

Having A Slow Caffeine Metabolism

hose with a slow caffeine metabolism are more likely to feel jittery, anxious, nauseous, and restless as a result of taking stimulant pre-workout. Switching to a stim-free blend will give you a lot of the same benefits without the side effects.

If You're Pregnant Or Breastfeeding Women

Caffeine is a stimulant that increases your blood pressure and heart rate. This can be unhealthy for pregnant or breastfeeding women and can impact the health of the child too.

The caffeine content is very high in pre-workout, so make sure you stick to a stim-free blend.

pregnant lady working out

Stimulant Vs Non-Stimulant Pre-Workout Differences

On the surface the different types of pre-workout can be very similar, but there are some key differences between each:

1. Ingredients

Both stim-free and regular pre-workout both contain a lot of the same ingredients. Amino acids like L-arginine are used to help maintain your immune system and promote faster recovery.

Branched-chain amino acids (BCAAs) are used to help improve endurance and reduce fatigue during a workout so you can push yourself further. Beta-alanine is also used to reduce the build-up of lactic acid and keep you training for longer.

Creatine is also usually found in most pre-workout and has been proven to boost muscle performance. [1]

The key difference between the two types of pre-workout is the stimulant. Caffeine is the key ingredient used by stimulant pre-workouts and is responsible for giving you energy.

It works to focus your brain and keep you feeling energized and alert throughout your workout, and average amount of caffeine in pre-workout contains anywhere from 150-450mg of caffeine.

Stimulant-free pre-workout often contains vasodilators instead of stimulants to try and mimic the effects.

These vasodilators (typically nitric oxide) dilate your blood vessels and help to improve the flow of oxygen through your body. This gives your body more energy and your muscles a better pump.

While both types of pre-workout will give you energy, non-stimulant pre-workouts don't contain caffeine, so the effects can be quite different.

Stimulant Vs Non-Strimulant Pre-Workout (Pump or Not?))

2. Calories & Carbs

he ingredients list for stim-free pre-workouts and regular pre-workout supplements is very similar, so the calorie and carb content is often identical.

Both types of pre-workout supplements tend to use artificial sweeteners to improve the taste, but these tend to be low calories so they can support muscle growth without ruining a diet. In fact, most pre-workout is completely calorie and carb-free.

Some people argue that caffeine-free pre-workout isn't as effective for helping you burn calories because you don't get the energy boost from the stimulant, so your heart rate doesn't get as high.

This is yet to be conclusively proven, but even though stimulant-free pre-workouts have been shown to improve blood flow, they probably don't help you burn as many calories.

3. For Bodybuilding

Pre-workout supplements are great for bodybuilders because they provide your muscles with critical ingredients that help improve muscle growth and muscle recovery.

The amino acids contained within stim-free pre-workout and regular pre-workout will help to improve your muscular endurance and decrease muscle soreness.

The best stimulant-free pre-workout will give you a  mega pump by helping you increase blood flow to muscle tissue. This is because the compounds encourage your body to produce nitric oxide, and this can leave you looking a lot more muscular.

However, this tends to be a short-term effect, and both types of pre-workout supplements will be beneficial for bodybuilding.

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4. For Energy Boost

The beta-alanine and nitric oxide agents within non-stim pre-workout supplements help improve your energy levels, which will improve your exercise performance.

While this does help you to perform better, you won't get the same energy boost as you do from a stimulant pre-workout.

The adenosine blocking effects of the caffeine help to improve your cognitive abilities and leave you feeling more alert. This can help to dramatically improve your training performance, so if you're looking to increase energy levels, you should use a stimulant pre-workout.

5. For Workout Performance

Work outperformance comes down to endurance and working muscles as hard as you can. Many pre-workout supplements contain a non-essential amino acid-like beta-alanine which stops fatigue from hitting your muscles. This is perfect for high-intensity exercise where you need to go full throttle for longer.

Caffeine-free pre-workout formulas are just as effective, but they lack the initial energy boost you get from the stimulant.

Only you know where you're up to in your fitness journey, but if you are still a beginner and need that extra pick me up to get you through a workout, then you are better off choosing a stimulant pre-workout supplement.

man working out after taking pre-workout

6. Safety

People tend to be familiar with regular pre workout, and they often ask 'are non-stim pre-workouts safe?'

Well, it's difficult to know 100% because most pre-workouts are a proprietary blend, so you can't see every single ingredient, but non-stim ingredients seem to be safe enough.

While they don't have caffeine, some have more nutrients and contain the amino acids which form the building blocks of muscle building.

In fact, stimulant pre-workout can actually be more dangerous. The main difference in ingredients is the caffeine, which can improve performance and increase alertness but also cause a lot of side effects for those who are sensitive to stimulants.

For example, caffeine can make you jittery, cause headaches, upset your stomach, and give you trouble sleeping. To make matters worse, you can experience these side effects for over 6 hours if you metabolize caffeine slowly.

Not everyone will experience these negative effects, but if you're pregnant or breastfeeding, then you really need to avoid caffeine as much as possible. [2]

7. Product Testing & Certifications

Pre-workout is generally considered safe for human consumption, but unlike other supplements, they aren't FDA approved.

Some people claim this is because they question their effectiveness; others claim it's because there can be side effects to your central nervous system. However, none of this has been proven.

It's difficult to know all the ingredients within different proprietary blends, and for that reason, most athletes avoid them. You should always look for a third-party approved pre-workout where outside companies (like ChromaDex) have assured the product.

There are a lot more certified stimulant pre-workouts on the market, but that's generally because there are fewer stimulant-free products.

8. Price Comparison

Pre-workout isn't cheap, and for pre-workout it's between $1.50 and $3 a serving.

The price tends to be almost identical whether you opt for non-stimulant pre-workout or stimulant pre-workout, but there is a bit more competition on the market for regular pre-workout, which makes it easier to find a good deal.

woman deciding between stimulant vs non-stimulant pre-workout

Can You Stack Stim & Non-Stim Pre-Workouts Together?

It may seem like it's one or the other, but you can actually stack stimulants together and mix them in your drink. This actually gives a range of benefits you wouldn't get from taking just one type:

3 Benefits Of Stacking Them Together

1. Fewer Effects From Caffeine

Mixing a stim and stim-free pre-workout means you can limit the caffeine intake. This helps you get a bit of a buzz from the stimulant but reduces the risk of feeling the negative side effects and shakiness that can come with larger doses.

2. Better Pumps

Non-stimulant pre-workout can give you greater pumps after a workout. This is largely due to the nitric oxide agents and beta-alanine, which increase blood flow across your body.

By combining non-stim and stim pre-workout, you'll get a better pump vs pre-workout on its own.

3. Longer Product Lifespan

This might seem like an obvious one, but if you're combining two products together, you'll be splitting each serving size in half. This extends the lifespan of the product and means you won't have to replace it as often.

Related Article - Does Pre-Workout Expire?

Stimulant Vs Non-Stimulant Pre-Workout FAQs

Do non-stimulant pre-workouts help with weight loss?

Non-stimulant pre-workouts will help improve your gym performance and recovery, which in turn will lead to weight loss. Stimulant pre is probably going to help you lose more weight, but both types of pre-workout are beneficial.

Can you take non-stimulant pre-workout every day?

Yes, it's usually fine to take non-stim pre-workout every day, and some blends actually contain ingredients that need to be loaded into your body to keep them saturated and maximize the benefits.

Does stim free pre-workout affect blood pressure?

Stimulant free pre-workout shouldn't impact your blood pressure, but if you do suffer from high blood pressure already, it's a good idea to stay away from pre-workout supplements altogether.

Does your body build a tolerance to pre-workout?

Yes, if you take pre-workout regularly for a long period of time, your body can start to adjust to the effects, and it won't impact you as much. It's usually a good idea to cycle your supplements and come off them every 6-8 weeks to allow your body to reset.

Are high stimulant pre-workouts safe?

Consuming high amounts of caffeine and other stimulants can have a negative impact on your body and cause side effects. It’s not a good idea to take high stimulant pre-workouts every day, but they are safe for most people when consumed in moderation.


Pre-workout supplements are great to maximize your performance in the gym and help you get more from your workout.

Stimulant pre-workout is best for most people because the caffeine helps to keep you alert, but stimulant-free pre-workout is a great alternative for those who are sensitive to caffeine.

Hopefully, this article has explained the pros and cons of each, and you now know which is best for you.

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1. https://jissn.biomedcentral.com/articles/10.1186/s12970-017-0173-z
2. https://americanpregnancy.org/healthy-pregnancy/pregnancy-health-wellness/caffeine-intake-during-pregnancy/
3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5749041/

Last Updated on August 21, 2023

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Andrew White

Andrew White is the co-founder of Garage Gym Pro. As an expert fitness professional (gym building nerd) with over 10 years of industry experience, he enjoys writing about everything there is to do with modern fitness & the newest market innovations for garage gyms. When he isn’t testing out products for his readers, he’s usually out surfing or playing basketball.