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If your goal is to lift heavy and build muscle, you might welcome a pre-workout that provides a nice pump. But what if you’re sensitive to caffeine jitters? Then Huge Supplements has you covered with their Pump Serum Stim-Free Pre-Workout. It’s meticulously formulated to enhance nitric oxide production and mental focus without a hefty dose of caffeine.

RELATED: Best Stim-Free Pre-Workout

We tried Pump Serum, and—spoiler alert—we liked it. We can tell you why thanks to GGR Senior Director of Fitness Content Kate Meier, NASM-CPT, USAW-L1, CF-L1. For this Pump Serum Stim-Free Pre-Workout review, Kate tested it to help you decide if it’s the best pre-workout for your supplement stack.

We’ll explain the science behind its formulation, compare its cost per serving, and share our tester’s honest opinions on its taste and solubility.

Medical disclaimer: This article is intended for educational and informational purposes only. It is not intended as a substitute for medical advice. For health advice, contact a licensed healthcare provider. GGR also recommends choosing a product that has been third-party tested for quality.

We’re Pumped to Share This Review With You

Here at GGR, we’re big on providing our readers (looking at you, rockstar!) with unbiased product reviews, and we have just the team to do it. We’re certified personal trainers, registered dietitians, elite coaches, professional athletes, and certified nutritionists, and we personally put these products to the test. We’ve tried dozens of pre-workouts, so we’ve seen the good, the bad, and the “did that even do anything?”

For fitness supplements, we give products a 1 to 5 rating based on important criteria, such as:

  • Formulation
  • Taste
  • Solubility
  • Side effects
  • Third-party testing
  • Price per serving

We don’t offer our two cents on anything that we haven’t personally put to the test. And our review of Pump Serum Stim-Free Pre-Workout is no exception!

Huge Supplements Pump Serum

Huge Supplements Pump Serum Non-Stim

GGR Score: 4 starstarstarstarstar

Product Highlights

  • Available in four flavors
  • Formulated to improve workout performance 
  • Claimed to increase pump and muscle fullness 
  • Claimed to enhance endurance and increase focus

Pros & Cons

Pros

  • Reportedly effective
  • No post-workout crash
  • Taste is popular
  • Mixes well

Cons

  • Sucralose may cause GI distress
  • Artificial ingredients
  • Expensive

Bottom Line

Although it does contain artificial ingredients, the Pump Serum Stimulant Free Pre-Workout powder is designed to pump you up for your next workout without any post-workout crash.

A Quick Look at Pump Serum

Huge Supplements was founded in 2020, so it’s still a relatively new company in the ever-growing and ever-evolving sports nutrition industry. However, they’ve quickly made a name for themselves with their products. Most are geared toward bodybuilding and filled with a variety of potent ingredients. Their stimulant-free pre-workout supplement is no exception.

Pump Serum is made in the USA in an FDA-registered facility and contains scientifically researched ingredients. It contains pomegranate extract, beetroot extract, GlycerPump, and Huperzine A—all formulated to increase blood flow and improve workout performance. Take it on its own or stack it with Huge Supplements Wrecked Pre-Workout for a moderate dose of caffeine.

Before You Buy

  • This product is pump-focused and doesn’t contain creatine or any ingredients that give you the high-energy effect of most pre-workouts.
  • Pump Serum is sweetened with the artificial sweetener sucralose, which some people are sensitive to.

Is Pump Serum Worth It?

Great question—this Pump Serum review will give you all the info you need to decide for yourself! In the meantime, there are a few groups who we think would benefit from this pre-workout and a few who might need to consider an alternative. At $1.37 per 1-scoop serving, this pre-workout is a pretty average price for this type of product. 

Great for:

  • Those who are sensitive to caffeine
  • Athletes who already have a favorite creatine supplement
  • Athletes who like flexibility in their doses

Not recommended for:

  • Those who want a pre-workout with creatine 
  • Competitive athletes who are tested for banned substances
  • GI systems that are sensitive to sucralose

Pump Serum Specs

Price per serving$1.37 per scoop
Serving size1 scoop (14.9 g) or 2 scoops (29.8 g)
FlavorsJungle Juice, Blue Razz, Strawberry Mojito, Island Dream, Cherry Berry
Caffeine dosage0 mg
Beta-alanine dosage0 mg
Creatine dosage0 mg
L-citrulline dosage4,000 mg
Other key ingredientsBetaine Anhydrous, L-Tyrosine, GlycerPump, BioPerine, Vasodrive-AP, Nitrosigine
SweetenersSucralose, Acesulfame Potassium
Third-party tested?No

Experience Using Pump Serum

Kate Meier, NASM-CPT, USAW-L1, CF-L1, and Senior Director of Fitness Content here at GGR, knows how to train hard and what to look for in a high-quality pre-workout formula. She put Pump Serum to the test and examined her experience from every angle. Her overall consensus? She gave it a thumbs up, saying, “You definitely feel a pump! Gets the blood flowing.”

Kate working out in a gym

Price Per Serving

Each tub of Pump Serum Stim-Free costs $54.95 and contains 40 one-scoop servings. One scoop of Pump Serum should be more than enough to get the job done, but Huge Supplements also gives you the supplement facts for two-scoop servings—if you’re really chasing that pump. If you’re mixing up one-scoop servings, you’ll come out of pocket around $1.37 per serving. If you decide to go for two scoops, you’ll pay $2.74 per serving.

Based on our scoring scale, Pump Serum earns a 3.5 out of 5 for its price per serving. It’s not the most expensive product on the market, but you can definitely find cheaper options.

Formulation

Pump Serum’s price tag might be a little hefty compared to other pre-workouts on the market, but that starts to make sense when you look at its ingredients list. We were so impressed that we gave it a 4 out of 5 for its formulation. Of course, it’s a caffeine-free, non-stim pre-workout, but it contains several components that offer similar effects without the dreaded caffeine crash.

A woman is shown drinking from a shaker cup.

Each serving of Pump Serum contains 4,000 milligrams of L-citrulline, a dose linked to1 improved nitric oxide synthesis, enhanced athletic performance, and reduced fatigue. But it doesn’t stop there. Pump Serum also contains GlycerPump, a highly concentrated glycerol powder that is said to support hydration, and choline bitartrate2, which plays a role in memory, mood, muscle control, and other brain and nervous system functions.

It fell short of a perfect score with us because of its lack of creatine and its use of sucralose. While not all pre-workouts contain creatine, many in this price range do. And as far as sucralose goes, not all GI systems are fond of this artificial sweetener. However, we only docked it a point.

RELATED: Best Pre-Workout Without Creatine

Taste and Solubility 

Taste and solubility fared well on our scoring scale, each earning a score of 4 out of 5. Kate tried the Cherry Berry flavor and was fond of the taste. “It isn’t incredibly tart, but it is definitely sweet. It does taste like cherry with berries,” Kate says. “Instructions say to mix it with 8-12 ounces of water; that made the taste too concentrated, so I mixed it with about 20 ounces and it was better.” 

A man is shown drinking a Pre-Workout in a gym.

Solubility also got a thumbs up. “It mixes well, but it seems to settle a little, so I just shook it before every time I took it. Doing that made every sip good,” she adds.

Side Effects

There were no adverse side effects to note with Pump Serum Stim-Free. You definitely get a pump going, but it doesn’t bring a significant boost in energy, which Kate points out is because of its stim-free formula. “Doesn’t have that high-energy effect, of course, because it’s stim-free.”

Overall, we gave Pump Serum a 4 out of 5 for side effects.

Third-Party Testing 

Since the FDA doesn’t regulate sports nutrition supplements, we’re big on companies that go the extra mile and get their products tested for safety and purity. Huge Supplements talks a lot about testing on their website, but it’s unclear what’s done by a third-party lab and what’s done in-house. Transparency goes a long way in trusting your supplement stack like this, so we gave Pump Serum a 3 out of 5 for third-party testing.

Pump Serum vs Transparent Labs Stim-Free Pre-Workout 

Transparent Labs Stim-Free Pre-Workout

Transparent Labs Stim-Free Pre-Workout

GGR Score: 4.08 starstarstarstarstar

Product Highlights

  • Stim-free pre-workout
  • No caffeine
  • 7 flavors available
  • Easily mix with water
  • Good for people who work out at night
  • Won't give you the jitters or tingling sensations

Pros & Cons

Pros

  • Free of artificial colors, sweeteners, and other additives
  • Non-stim (no caffeine)
  • Won't give you the jitters
  • Designed to increase nitric oxide uptake in the muscle cells
  • Can subscribe and save

Cons

  • Those who want caffeine should look elsewhere
  • Doesn't contain creatine or BCAAs

Bottom Line

Transparent Labs Stim-Free Pre-Workout is an uncaffeinated pre-workout powder that will not give you the jitters or tingling commonly associated with pre-workout supplements. This pre-workout contains a blend of citrulline malate, beta-alanine, L-tyrosine, taurine, and elevATP, a compound claimed to increase ATP activity in muscle cells.

You know a review from us isn’t complete without a thorough comparison to a competitive product. So, without further ado, let’s compare Pump Serum Stim-Free with Transparent Labs Stim-Free Pre-Workout. You’ll notice the major differences in third-party testing, beta-alanine content, and sweeteners used. 

Learn more with our full Transparent Labs Stim-Free Pre-Workout review.

Huge Supplements Pump Serum Stim-Free Pre-WorkoutTransparent Labs Stim-Free Pre-Workout
Price per serving$1.37 per scoop$1.67
Serving size1 scoop or 14.9 g1 scoop or 20-23 g (depending on flavor)
FlavorsJungle Juice, Blue Razz, Strawberry Mojito, Island Dream, Cherry BerryBlue Raspberry, Cherry Limeade, Orange, Peach Mango, Sour Grape, Strawberry Lemonade, Tropical Punch
Caffeine dosage0 mg0 mg
Beta-alanine dosage0 mg4,000 mg
Creatine dosage0 mg0 mg
L-citrulline dosage4,000 mg8,000 mg
Other key ingredientsBetaine Anhydrous, L-Tyrosine, GlycerPump, BioPerine, Vasodrive-AP, NitrosigineBetaPure Betaine Anhydrous, Taurine, L-Tyrosine, SenActiv, elevATP, BioPerine, Huperzine A, Himalayan Sea Salt, Potassium Chloride
SweetenersSucralose, Acesulfame PotassiumStevia Extract
Third-party tested?NoYes, Informed Sport

Customer Experience 

We didn’t need customer service during our experience with Pump Serum, but we did make note of their returns policy. There is no money-back guarantee. However, you can return unopened and unused products within 14 days of your purchase. This is a pretty tight timeframe, so you might want to be sure when ordering from Huge Supplements.

Ordering Pump Serum

Huge Supplements gives you two ways to order their products on the company site. You can order Pump Serum as a one-time purchase at full price or set up a delivery subscription to save 10% on each order. You can also order a stack of supplements for increased savings. Buy two products for a 5% savings or three products for a 10% savings. Plus, you can get free shipping if you spend at least $100 per order. Orders placed Monday through Friday are said to ship the same day and should arrive in one to three business days.

A person's back can be seen while they stand in a gym lifting weights with the Gymreapers Quick-Lock Belt.

If you prefer the Amazon way, you can also find Pump Serum on Amazon Prime for the same price. You can also subscribe and save on Amazon.

Customer Reviews

Pump Serum boasts a rating of 4.7 out of 5, averaging 1,672 customer reviews on the brand’s website at the time of writing. Many customers echoed Kate’s thoughts, highlighting the pumps they got from this pre-workout formula. Still, some reviewers were disappointed with its effects and did not care for the taste.

Final Verdict of Our Pump Serum Stim-Free Pre-Workout Review

Sometimes, caffeine-free pre-workouts leave you wanting more, but that’s not the case with Pump Serum Stim-Free Pre-Workout—at least in our experience! We think Pump Serum is true to its name and does a pretty good job of giving you a solid pump. We were pleased with our overall experience, and we can get behind all the science-backed ingredients.

  • There isn’t a huge boost of energy that comes with taking Pump Serum, but you’ll likely notice a solid pump.
  • You can take 1 or 2 scoops, depending on your needs. Each scoop costs around $1.37 when ordered at full price.
  • There is no creatine in Pump Serum, so you might need a creatine alternative.
  • Pump Serum is not third-party tested.
  • Huge Supplements’ products are made in the USA.

Full Rating

Huge Supplements Stim-Free Pre-Workout

Although it does contain artificial ingredients, the Pump Serum Stimulant Free Pre-Workout powder is designed to pump you up for your next workout without any post-workout crash.

Product Brand: Huge Supplements

Product Currency: $

Product Price: 54.95

Product In-Stock: InStock

Editor's Rating:
4

Huge Supplements Pump Serum Rating

Price per serving – 3.5
Formulation – 4
Taste – 4
Solubility – 4
Side effects – 4
Third-party testing – 3
Customer service – 4
Customer reviews – 4.7
Buy Now

Pump Serum Stim-Free Pre-Workout: FAQs

Is stim-free pre-workout good?

Yes, stim-free pre-workouts can be a great addition to your supplement stack when added in mindfully. They may not give you the same boost of energy that your typical caffeine-containing products will, but many contain a blend of ingredients that offer comparable results.

When should I take Pump Serum?

Huge Supplements recommends taking Pump Serum approximately 30 minutes before you hit the gym.

Does non-stim pre-workout make you stronger?

Non-stim pre-workouts can support your efforts in the gym, but it’s important to remember that supplements aren’t magic. Non-stim pre-workouts can improve blood flow and focus to help you maximize your training and get stronger over time.

Is Pump Serum worth it?

Everyone has unique preferences and responds to supplements differently, but we think Pump Serum is worth a shot.

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any diseases.

References

  1. Park HY, Kim SW, Seo J, et al. Dietary Arginine and Citrulline Supplements for Cardiovascular Health and Athletic Performance: A Narrative Review. Nutrients. 2023;15(5):1268. Published 2023 Mar 3. doi:10.3390/nu15051268
  2. National Institutes of Health. Choline.

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