The 5 Best Stim-Free Pre-Workouts to Improve Your Performance

Pre workouts are an extremely popular supplement to pump your exercise to the next level. However, they come packed with caffeine and many other stimulants that have strong side effects. If you want to avoid these, the best stim- and caffeine-free pre-workouts will be a godsend.

Transparent Labs stim free pre-workout

Transparent Stim-Free

  • Great taste
  • Only ingredients that help you
  • Backed by peer-reviewed research
Legion Pulse best pre workout

Legion Pulse

  • Helps you get into the zone
  • Affordable
  • Money-back guarantee

Pump Serum

  • Incredible pump- biggest servings
  • Best for serious gymgoers
  • Multiple flavors

Pre-workout supplements can give you an incredible boost for your workout or sports event. However, the quality, ingredients and dosages can vary hugely. Furthermore, in order to provide you with a big energy boost, they often have an excess of caffeine or other strong stimulants. As such, it can be hard to find the best stim- and caffeine-free pre-workout supplements.

That said, it is not necessary to have caffeine in your pre-workout to notice a positive effect on your training. In fact, more and more people are weary of the adverse effects caffeine can have on your body or simply don’t want to handle 100mg in the late afternoon. Obviously, among other things, this can cause sleep issues, uneasiness, jitters etc. Thus, taking the best caffeine-free pre-workouts will help you avoid this.

Similarly, theacrine and other stimulants might increase your stress levels, and cause nausea or other nasty side effects. Starting with the top stim-free pre-workouts will definitely change your life.

Our Top Picks for Caffeine-Free Pre-Workouts

Let’s have a look at our top picks:

  1. Best Stim-Free Pre-Workout: Transparent Labs Stim Free
  2. Best Value Caffeine-Free Pre-Workout: Legion Pulse
  3. Best Stim-Free Preworkout without Beta-Alanine: Pump Serum
  4. Best Stim-Free Pre-Workout in Europe : Raze Zero Caffeine
  5. Best All Around Pre-Workout Without Caffeine: Gorilla Mode Nitric Oxide

Pre Workouts vs Stim Free Pre-Workouts

Many of you might be skeptical of the benefits the best stim-free pre-workouts can have. After all, isn’t that stimulus or boost what we are looking for in a pre-workout?

Well, yes and no. Stimulants like caffeine or theacrine are certainly proven to boost your athletic performance. Therefore, there’s no denying that you will get a smaller boost from stim and caffeine-free pre-workout supplements.

However, ingredients like beta-alanine, l-citruline, alpha-GPC etc. can also increase vascularity, increase your athletic performance, reduce fatigue and increase recovery speed.

Therefore, with the best stim-free pre-workouts you will still feel noticeable improvements in your training.

Key Takeaways – Who Should Take Stim-Free Pre-Workouts

  1. People who train late
  2. Those who have caffeine intolerance
  3. People looking to avoid side effects from normal pre-workouts (lack of sleep, jitters…)

5 Benefits of Stim-Free Pre-Workout Supplements

However, there are also research-backed benefits to taking stim-free pre-workouts:

  1. No secondary effects
  2. Improved sleep, improved recovery
  3. Help you reset
  4. Reduce soreness
  5. Slow down fatigue build-up

To the first point, caffeine free preworkouts will cause you no jitters, no nausea, and might reduce your anxiety and stress. In fact, if you are having issues with anxiety, you probably don’t want to have much caffeine.

Secondly, standard pre-workouts can interfere with your sleep, particularly if taken late. This is a big issue, since sleep is the first step in recovery and getting ready for your next workout. Good sleep also can help with recovery from injuries.

Thirdly, one thing that we often overlook is our caffeine dependency. The effect caffeine has on our body diminishes over time. With caffeine-free pre-workouts you can reset your caffeine tolerance so that you can enjoy the full benefits the next time you consume a full pre-workout.

3 Benefits of Normal Pre-Workouts

Are caffeine-free pre-workouts perfect then? Should we all move to stim-free preworkouts?

Well, no. There are still plenty of advantages to taking a “normal” pre-workout.

Caffeine in Pre-Workouts: The Good and the Bad

There’s no denying that caffeine is one of the best ingredients in a pre-workout supplement. It can help you “wake you up”, set up your mood, and get into the zone.

Furthermore, it can also increase the length of time in which you can perform at your best.

A dose of 3 to 6mg of caffeine per kg of bodyweight caffeine 20 minutes before training can be enough to achieve these positive effects.

However, it also comes with drawbacks like negatively affecting your sleep, increasing anxiety, and stress, jitters etc.

There’s also the fact that your body will get used to caffeine and the effect will be diminished over time. That’s why resetting your caffeine tolerance can be proven beneficial to your training.

Furthermore, many pre-workouts use excessive amounts of caffeine, which almost reach the daily recommended amount in a single dose (400mg).

This is where the best caffeine-free pre-workouts can help you out.

Best Stim-Free Caffeine-Free Pre-Workouts at a Glance

Best stim free

Natural Best Stim-Free Pre-Workout

Transparent Labs

  • Only contains science-backed ingredients
  • Very effective when tested
  • Great for fatigue reduction

Best Caffeine-Free Pre-Workout for Men

Legion Pulse

  • Best at helping you get in the zone
  • Tons of delicious flavors
  • Money-back guarantee

Best Stim-Free Pre-Workout in the UK

Raze Zero-Caff

  • Contains Creatine
  • Good for cellular hydration
  • Bigger pump

Best Caffeine-Free Pre-Workout w/o Beta Alanine

Pump Serum

  • Largest servings
  • Incredible pump
  • Great for extra endurance

Best All-Around Stim-Free Pre-Workout

Gorilla Nitric Mode

  • Most comprehensive formula for NO production boost
  • Good for power and energy increase
  • Huge servings

Meet the Expert

Enaut editor of Latestfuels

Hello, my name is Enaut and I’m the owner of Latestfuels.

Ever since I started my BSc in Biochemistry at the University of Bath I’ve been obsessed with nutrition, health, and sports performance.

I’ve lifted for over 12 years, done competitive sports for 18 and participated in solo- and team sports since I was a kid.

My goal has always been to give 120% in everything I do.

For that, I learned a shit-ton about nutrition, supplements, and body chemistry. Now, I try to test that knowledge and provide clear information so you can make an informed choice.

Best Stim-Free and Caffeine-Free Pre-Workouts

1. Transparent labs Stim Free Pre-Workout — Best Stim-Free Pre-Workout

Best Stim-Free Pre-Workout


  • Science-backed ingredients only
  • High dosages
  • Very effective when trialed
  • Great at reducing fatigue
  • No artificial flavoring – 10 flavors


  • No creatine

When looking at the best stim-free preworkouts, you will always find Transparent Labs Stim Free is mentioned. Why? Because Transparent Labs uses peer-reviewed research to choose ingredients and add them in relevant quantities.

For instance, they add 6mg of citrulline – the effective dosage is 4 to 10mg-, which is considerably more than other pre workout supplements. L-citrulline is a natural compound that is converted into L-arginine which in turn boosts nitric oxide (NO) production. This is key, since boosting nitric oxide levels increases blood flow and widens your blood vessels, improving exercise performance and recovery.

Besides, I love pre-workouts that help me get into “the zone” and boost focus. Often, caffeine and L-theanine are used to achieve this effect. However, as caffeine-free pre workout Legion uses alpha-GPC, a choline precursor. Choline is a key precursor to the motor neurotransmitter acetylcholine.

They also add beta-alanine and betaine, both of which have proven beneficial effects in fatigue reduction during exercise allowing you to lift for longer.

This is a caffeine free version, but Legion also offers a pre workout supplement with some caffeine for those who want the extra boost.

2. Legion Pulse Pre-Workout — Best Pump Stim-Free Pre-Workout for Men



  • Nootropics + amino acids for bigger pump
  • Effective at helping you focus and increasing endurance
  • Affordable
  • Multiple delicious flavors
  • 100% money-back guarantee
  • Lab tested


  • Only 20 servings per tub
  • Could include Huperzine A

Legion’s Pulse pre-workout has been a staple among the best stimulant free pre workouts for a while. Their caffeine and stimulant-free formula contain only researched-backed ingredients and nothing else.

Unlike other top stim-free pre workouts Pump Surge includes some nootropics, namely Alpha GPC (300mg). Alpha GPC acts in the acetylcholine neurotransmitter pathway used during exercise.

Besides, betaine, L-citrulline, and beta-alanine will boost your nitric oxide levels helping vascularity, muscle growth, and nutrient delivery. All of these are found in clinically effective dosages, which is a big plus.

Furthermore, I love the fact that they add 0 artificial sweeteners and flavours, which improves the taste. It makes it for a great US made product, and it’s even lab tested for impurities.

Out of all the flavors, I recommend starting with Blue Raspberry. Some of the best tasting zero caffeine pre-workouts you’ll find around.

3. Raze Pre-Workout by Protein Works — Best Stim-Free Pre-Workout in the UK

Raze Zero Caff best caffeine free pre workout in the UK


  • Includes creatine, the most proven supplement to boost exercise
  • Extra effective hydrating your muscles
  • Helps you with pump
  • Well-priced, fast-shipping
  • Clean label, no hidden ingredients


  • Low L-citrulline dose
  • Could have more NO boosters

In the UK, you will struggle to find a better caffeine-free pre-workout than Raze Free Caff. I personally love the inclusion of creatine monohydrate, which is proven to increase strength, boost power and recovery during workout, and increase muscle tissue size.

Creatine monohydrate supplementation is not only safe, but possibly beneficial in regard to preventing injury and/or management of select medical conditions when taken within recommended guidelines.

T.W. Buford et al, International Society of Sports Nutrition position stand: creatine supplementation and exercise.

On top of creatine, Raze also adds Taurine, L-citrulline, glycerol powder and a vitamin blend to increase both physical and mental performance. For instance, glycerol goes well with creatine as increases muscle hydration and boosts aerobic and anaerobic performance. A great muscle building combo.

One of the downsides of Raze vs the other best stim-free pre-workouts is that it has lower dosages and it’s not as effective as a nitric oxide booster.

That said, upon using it, I still found it extremely effective at increasing my performance and helping me push through the workout.

4. Pump Serum — Best Stim-Free Pre-Workout for Men

Pump Serum best stim-free pre-workout for men


  • Huge servings – extra effective
  • Incredible pump
  • Natural ingredients to help you with blood flow
  • No beta-alanine (no tingling)
  • Increases muscle swelling


  • Expensive

Pump Serum offers some of the biggest servings among the best stim-free pre-workouts with a whooping 31g. Higher dosages will be especially helpful for men and those who carry more muscle.

As mentioned with some of the other pre-workout formulas, Pump Serum has 8g of L-Citrulline (effective dosage) to increase nitric oxide production. However, it also adds 254mg of VasoDrive-AP and 1g of Pomegranate extract to increase blood flow (synergistic).

All in all, when trying out Pump Serum I got some of the biggest pumps out of all the stim free pre-workouts tested for this review. I was absolutely on fire in my gym session, and I kept using it even after the review.

Great buy.

5. Gorilla Mode Nitric — Best Caffeine-Free Pre-Workout

Gorilla Nitric Mode best caffeine-free pre-workout


  • Focused on increasing NO production
  • Great for vascularity, power and energy increase
  • Tons of flavors to choose from
  • Bulk discounts
  • Huge quantities of active ingredients
  • Good for high-intensity exercise


  • Not sold in EU
  • Gritty texture

Gorilla Nitric Oxide is the most comprehensive and stacked caffeine-free pre-workout in the US. It attacks NO production from multiple angles:

  • 10g of L-citrulline + 1.5g of Nitrosigine + 1.5g of Agmatine sulfate –> saturate arginine-eNOS pathway for nitric oxide production
  • Nitrate–nitrite–nitric oxide (NO) pathway tackled with 750mg of sodium nitrate

This is important since a singular pathway can be saturated (slowed down) by enzymes, thus nitric oxide production can be slower than expected. The synergistic approach can improve blood flow, reduce muscle soreness and increase muscle recovery.

Besides, there’s 5g of creatine monohydrate that help out on ATP production (cellular fuel) and intracellular hydration, together with 4g of glycerol. Similarly, vasodilation is increased by VasoDrive-AP by inhibiting ACE.

On top of that, malic acid (3g) can act as an intermediary on the KREBS cycle and slow down lactic acid buildup during workouts (reduce fatigue build-up).

Without a doubt, as it can be seen in the Youtube video below by Derek (MPMD), Gorilla Nitric Mode is one of the most powerful pump caffeine-free pre-workouts in the market.

However, one can argue that starting at lower dosages might be beneficial if you are not used to pre-workouts.

Stimulant Free Pre Workout Ingredients

So besides being caffeine-free, what should and should not a stimulant free pre include?

Which are effective pre workout ingredients and which ones can you skip?

Starting by what WON’T find in non stim pre-workout supplements:

  • Caffeine
  • Yohimbine
  • Theacrine
  • Guarana
  • DMAA (now banned)

In fact, you should make sure to buy your pre workout supplements from reputable brands like Transparent Labs, Optimum Nutrition, Huge Supplements, MyProtein etc.

Do not purchase brands with few reviews, or proprietary blends that hide which ingredients they contain. These will not only harm your wallet but could be a health hazard and ultimately ruin your workout session.

The best pre workout supplements will ALWAYS have clean ingredients, and be transparent about their ingredients.

Common Ingredients in Non Stim Pre Workouts

On the opposite hand, there are multiple ingredients that you will find in your non stim pre workout.

  • L-citrulline
  • Malic acid
  • Creatine Monohydrate
  • Beta-alanine
  • Taurine
  • Glycerol
  • Alpha GPC
  • etc

For instance, beta alanine is an amino-acid often added to reduce muscle soreness and reduce muscle fatigue. However, it often causes itchiness 15 minutes after consumption which many find uncomfortable. That’s why you won’t find in some of the best pre workouts.

On the other hand, L-citrulline is a MUST-have in any solid pre-workout supplement. It’s a nitric oxide booster that helps enhance blood flow, increases muscle pumps, and muscle growth, and helps muscle building.

Ingredients Found in Most Pre Workout Supplements

In the table below, you see what each of the ingredients mentioned above do and how they can help you increase workout performance.

IngredientEffectStim FreeSide Effect
CaffeineIncreased energy, focus, performance
Reduced fatigue
NoSleep depravation
Increased anxiety
YohimbineIncreased alertness
Body in “fight-or-flight” status
NoHigh blood pressure
Increased anxiety
TheacrineIncreased mental clarity
Mood booster
GuaranaIncreased energy and focusNoJitters
Sleep depravation
L-citrullineBoost nitric oxide production
Boost vascularity, cellular hydration
Malic AcidIncreased creatine absorption
More endurance, reduce fatigue
CreatineIncreased cellular energy
Promote muscle protein synthesis, increased lean mass
YesKidney stones
Beta alanineReduced muscle soreness and fatigueYesItchiness
TaurineIncrease aerobic capacityYesStrain on your kidneys
Alpha GPCReduce muscle fatigueYes
GlycerolCellular hydrationYesHeadache

How to Use Pre-Workouts

When it comes to using your favorite non stimulate pre workout, I recommend following the next steps:

  1. Take 15-30 minutes before your workout
  2. Drink plenty of water after consuming it
  3. Make sure you’ve eaten 1h before exercise

While this might seem obvious to some they are incredibly important. Cellular hydration can’t happen without proper hydration. Obvious, isn’t it? If you don’t drink enough water you will be inhibiting nitric oxide action and reducing the benefits of taking the pre-workout.

Furthermore, unless you are on a diet, I recommend eating an hour before doing exercise. The exact period will depend on how well you deal with food digestion. However, if you are looking to push yourself to the extreme, you need to make sure you have the fuel for it.

Besides, I recommend you have a balanced diet outside the pre-workout meal. I often consume meal replacement shakes because they allow me to track what I eat, consume healthy meals on the go, get quality protein in my body while they also provide me with vitamins and minerals.


Do Stim-free pre-workouts work?

Yes, stim-free pre-workouts do work. They might not provide the same intense energy boost that caffeinated pre-workouts do, but they can still help improve your performance during exercise thanks to their other ingredients like beta-alanine, l-citrulline, and alpha-GPC.

Are stim-fee pre-workouts safe?

Yes, stim-free pre-workouts are perfectly safe when used as directed. In fact, they can actually be beneficial for your health since they won’t interfere with your sleep or increase anxiety levels like some caffeinated pre-workouts can. You won’t find doubtful substances like DMAA (banned) or Yohimbine, for example.

Are regular pre workout supplements better than non stimulant pre workouts?

Yes and no. While they are slightly more effective at increasing cognitive and workout performance, there are still many benefits you’ll get from caffeine free pre-workouts. This includes better recovery, increase in nitric oxide production, vascularity, reduce muscle fatigue…

What are the benefits of taking non stimulant pre workout supplements?

There are still many benefits to caffeine free pre-workout supplements like increased blood flow, increased mental focus, reduce muscle fatigue, reducing muscle soreness, and overall boost to your workout performance.

Are BCAAs necessary in my low caffeine pre-workout?

No. Branched Chain Amino Acids are helpful to build muscle but there’s no enough evidence that they are effective as pre-workout. Other pre-workout brands will add branched-chain amino acids because they are cheap ingredients.

How long do stim-free pre-workouts last?

The effects of a stim-free pre-workout will typically last for about four to six hours. This is longer than the effects of a caffeinated pre-workout, which only lasts for one to two hours.

Verdict – Best Stim- & Caffeine Free Pre-Workouts

While both stim and stim-free pre-workouts have their benefits, I believe that the best way to take advantage of them is by cycling them.

This means that you should take a break from stimulants every few weeks or months. And during those times, you can still improve your performance by taking the best stim-free pre-workouts.

This way you can avoid the negative side effects of stimulants, while still getting the benefits of increased performance.

So, if you are looking for the best stim-free pre-workouts, here are my top picks:

  • Stim Free by Transparent Labs — Best Overall
  • Pump Serum by Huge Supplements— Top Stim-Free Pre-Workout without Beta Alanine
  • Pulse by Legion Athletics — Top Stim-Free Pre-Workout for Men

Each of these products contains ingredients that have been proven to be effective at increasing performance.

Do you have any experience with stim-free pre-workouts? Let us know in the comments below.