The benefits of pre-workout are well-known, but there are many different types, 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, I'm here to help; in this article, I'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.

Just make sure to eat a well-balanced breakfast first and postpone pre-workout ingestion at least 60 minutes after working out to mitigate potential crashing later on in the day.

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.

Caffeine can help boost your metabolism and thermogenesis, increase your heart rate, and ultimately help you burn more calories, leading to greater fat loss during your workouts.[1]

Advanced Lifters Looking For All-Around Athletic Performance Boost

A well-rounded and well-dosed pre-workout with a high caffeine dose can elevate every aspect of physical performance, helping advanced gym-goers, powerlifters, and bodybuilders progress as they come closer to their plateau.

For advanced lifters and bodybuilders, a pre-workout should contain at least 300 mg of caffeine, 6000 mg of L-citrulline, 1500 mg of L-tyrosine, and 150 mg of L-theanine.

Endurance Athletes And Long-Distance Runners

Endurance athletes and long-distance runners can greatly benefit from stim pre-workout supplements, whether they're taking them before a workout session or an event.

Unless pre-workout supplements are forbidden in an event, a potent dose of caffeine (for instance, 3-6 mg/kg) can enhance energy and strength for up to three hours, depending on the dose or individual's weight, giving them enough of a boost to complete most challenges, including running a full marathon.

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, you'll be better off with a stimulant-free supplement, as high stimulant dosages can cause difficulty falling asleep, as well as staying asleep.

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, impact your gains, and sidetrack your recovery. 

Taking a stim-free pre-workout will let you work out late without impacting your sleep schedule and recovery.[2]

If You Have A Slow Caffeine Metabolism Or Low Tolerance

Those with a slow caffeine metabolism or low tolerance 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 benefits in the other athletic performance areas without causing you any stimulant-related side effects.

If You're Pregnant Or Breastfeeding Women

Caffeine is a stimulant that increases your blood pressure and heart rate and is considered potentially unhealthy (in doses surpassing 200 mg) for pregnant or breastfeeding women and can impact the health of the child, too.

If You Have Existing Cardiovascular Issues

While caffeine could be good for the heart, for those with pre-existing cardiovascular issues, stim-free pre-workouts eliminate the risk of increased heart rate, arrhythmia, and high blood pressure that stimulants like caffeine could potentially induce. 

If You Have Suffer From Digestive Issues

Non-stim pre-workouts are often better tolerated by individuals with digestive issues because they don't contain ingredients like caffeine or other stimulants, which can cause gastrointestinal distress such as acid reflux, stomach cramps, pain, nausea, and diarrhea.

If You Struggle With Anxiety Disorder

For individuals with anxiety, stimulant-free pre-workouts are generally a much better option.

Stimulants like caffeine can be an anxiety trigger, especially in high dosages, and could exacerbate symptoms of anxiety, such as increased heart rate, restlessness, sweating, difficulty breathing, and nervousness.

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

The most obvious difference between stim and non-stim pre-workouts is stimulant content.

The average amount of caffeine in pre-workout is anywhere from 150-400 mg, with some pre-workouts containing as much as 650 mg of caffeine in a single serving. Non-stim pre-workouts, on the other hand, do not contain any caffeine or stimulants.

As far as the other ingredients go, both stim and non-stim pre-workouts contain the same ingredients, such as:

Nitric Oxide Boosters

Cognitive Boosters

Performance Boosters













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

2. For Weight Loss

Overall, stimulant pre-workouts are a slightly better option for weight loss as caffeine is a known weight-loss aid, with the keyword being a "slightly better option".

The reason the difference between the two is minimal is that there's only so much help you can get from thermogenic aids such as caffeine. For proper and effective weight loss, the only significant factor is the caloric deficit, and both stim and stim-free pre-workouts are very low in calories.

3. For Bodybuilding

Regular pre-workouts will be a better option for bodybuilding as caffeine is arguably the most important performance enhancer found in pre-workout supplements.

Caffeine in regular pre-workouts can significantly increase strength and energy, both absolutely essential in the bodybuilding context.[3] In addition, a stim pre-workout will contain all the other active ingredients, just like a stim-free pre-workout, so the focus, endurance, and muscle pumps will be equally elevated.

Naturally, all of this is highly dependent on the specific pre-workout products, but if we assume every active ingredient in both formulas is dosed equally, a pre-workout with caffeine will be better.

recommended pre-workout!

Transparent Labs BULK Pre-Workout







Overall Rating


4. For Energy Boost

The adenosine-blocking effects of caffeine help mitigate feelings of fatigue and tiredness and leave you feeling more alert and energetic.

This can help improve your training performance dramatically, so if you're looking to increase energy levels, you should use a stimulant pre-workout.

man working out after taking pre-workout

5. Safety

While both regular and stim-free pre-workouts are considered safe, there is a lower chance of stimulant-associated side effects occurring with stim-free pre-workouts. In other words, stim-free pre-workouts are safer.

For example, caffeine can make you jittery and anxious, speed up your heart rate and elevate blood pressure, cause headaches, upset your stomach, and give you trouble sleeping. To make matters worse, you can experience these side effects for several hours if you metabolize caffeine slowly.

To be fair, not everyone will experience these negative effects, but if you sometimes do, a stim-free pre-workout is a logical choice.

7. Product Testing & Certifications

Each company is responsible for product testing, which is usually done by a third-party tester and does not differ based on pre-workout ingredients or lack thereof. Some companies choose to do this, some don't. More importantly, pre-workouts aren't subject to FDA testing and aren't FDA-approved.

One thing to note is that the FDA can intervene at any point if it decides that a product is unsafe for human use and remove the product from the shelves.

This usually happens due to stimulants found in pre-workouts and has happened several times before - like with Dark Energy pre-workout, which contained a banned substance, DMAA.

8. Price Comparison

Pre-workout cost is rarely dictated by its ingredients, especially caffeine, which is incredibly affordable. Therefore, 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.

That said, an average pre-workout is around $1.50, but the price can vary from $0.5 to $3 per serving.

woman deciding between stimulant vs non-stimulant pre-workout

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

Yes, you can stack stim and non-stim pre-workouts together. You can use a non-stim pre-workout to increase the dosages of other notable ingredients, such as citrulline or theanine, without increasing your stimulant dosage simultaneously.

Stacking non-stim with stim pre-workout (meaning the other way around) does not make sense, as it defeats the purpose of a non-stim pre-workout in the first place.

5 Benefits Of Stacking Them Together

1. Fewer Side Effects From Caffeine

As we said, mixing stim with non-stim pre-workout can help you hit the higher ends of the clinically efficacious dosages of active ingredients in the pre-workout formula without raising the caffeine dose.

By keeping the caffeine dose moderate, you minimize (or even eliminate) the possibility of any caffeine-induced side effects, such as anxiety or jitters.

2. Better Pumps

It is not uncommon for regular pre-workouts to have minimal or below the minimal clinically effective dosages of NO-boosting compounds such as citrulline or Nitrosigine, meaning your pumps would be mediocre.

Stim-free pre-workouts, on the other hand, usually contain a lot more NO-boosting compounds in order to compensate for the lack of stimulants, meaning combining the two could give you massive pumps.

3. Improved Focus

While this might seem counterintuitive since caffeine is a known cognitive booster, adding a scoop of a stim-free pre-workout instead of double-scooping your regular one could improve your focus even further in two ways.

  1. Too much caffeine can be overbearing, leading to overstimulation and making you feel scatterbrained instead of focused.
  2. Stim-free pre-workout formulas often contain nootropics such as L-theanine, Alpha-GPC or choline, which are known to improve your cognitive performance while working in ways different from caffeine.[4]

4. Reduced Caffeine Tolerance

If you decided to take a little break from high caffeine dosages to help reignite its efficacy and lower your tolerance, you could start by gradually reducing the dose instead of going cold turkey, by mixing half a scoop or regular and half a scoop of stim-free pre-workout.

While caffeine withdrawal symptoms aren't severe, the lack of buzz you're accustomed to before training may cause you to perform inadequately for the time being.

5. Better Endurance

Once again, circling back to dosages of other active ingredients, adding a non-stim formula to your regular pre-workout will likely result in better muscular endurance.

If you hit the higher end of the maximum clinically efficacious dosage for ingredients such as citrulline or Nitrosigine, your endurance will receive a significant boost, allowing you to train, run, cycle, or play sports longer.

Stimulant Vs Non-Stimulant Pre-Workout FAQs

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

Non-stimulant pre-workouts don't directly help with weight loss, as they're commonly void of any thermogenic aids. However, they will aid your gym performance, which in turn will lead to weight loss.

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

Yes, you can safely take a non-stimulant pre-workout every day, as long as you stick to the recommended dosages and choose quality products.

Does stim free pre-workout affect blood pressure?

Stimulant-free pre-workout could impact your blood pressure. Compounds such as citrulline relax blood vessels and improve circulation, but can also lower your blood pressure.

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 high-stim pre-workout 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, both short and long-term. However, as long as your daily caffeine dose does not exceed 400 mg, there shouldn't be any long-term consequences if you're otherwise healthy.


Overall, a regular pre-workout will be a better choice for most gym-goers. While there's certainly a place for a non-stim pre-workout in your supplement stack, there is a clear reason why caffeine and other stimulants are the backbone of pre-workout supplements.

The only thing to keep in mind is that for this statement to be factually true, you must choose a solid, well-formulated pre-workout supplement, like the one below.

recommended pre-workout!

Mixing Transparent Labs BULK Pre-Workout







Overall Rating




Last Updated on November 7, 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.