Pre JYM Pre Workout
JYM Supplement Science

Pre JYM Pre Workout

Food Supplement
Pre Workout with High Quality Ingredients
9.1  out of 10  (4,063 Reviews)
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Product Overview

"Welcome to my latest creation, JYM Supplement Science. JYM combines real science with real ingredients to deliver unreal results. Pre JYM, my cutting-edge pre-workout product, has revolutionized the pre-workout category."

Supplement companies love to claim they've created a real “game-changer.” Pre JYM doesn't play that game. It doesn't need hype or flashy marketing. With 13 hand-picked ingredients included at full amounts, Pre JYM is in a league of its own.

Put simply, Pre JYM is the most effective pre-workout supplement I've ever developed. It's built on solid science and decades of professional experience. Nothing is hidden, and there is no filler. Pre JYM is research made real. It's pure pre-workout fuel."

Hit the JYM!

Jim Stoppani, PhD
Owner, JYM Supplement Science

The Power of Pre JYM
No Proprietary Blends

Look at the supplement facts panel on your favorite pre-workout product and you'll most likely see the term “proprietary blend.” Supplement companies want you to think this means they've created a special blend of ingredients that magically work together to deliver unique results. Because this blend is so amazing, they have to keep the amounts of each ingredient secret so no other company steals the formula.

The truth, however, is that propriety blends can serve a different purpose. They allow some supplement companies to hide how little of each ingredient they've actually put in a product. This can result in cheap, under-dosed, ineffective supplements.

Pre JYM doesn't use proprietary blends. Take a look at the supplement facts panel and you'll see the actual amounts of all ingredients. I have nothing to hide. I'm proud of the amount of each and every ingredient I've included.

Proper Amounts

For the reasons detailed above, many supplement companies are moving toward transparency and axing proprietary blends. That's a good thing. However, some of these companies are still guilty of grossly under-dosing ingredients.

Take citrulline malate, for example. The research on this potent amino acid shows that you need 6 grams per serving. Most pre-workout products leave out citrulline entirely, and only a few of them provide anywhere close to 6 grams.

No "Abbreviated" Formulas

A handful of companies are as fed up as I am with proprietary blends and under-dosed formulas, but they fall short by using “abbreviated” formulas. An abbreviated formula is one that uses proper dosing of all ingredients, but only includes a few ingredients.

Take, for example, a pre-workout formula that includes beta-alanine, creatine, caffeine, and tyrosine. There's nothing wrong with it, but it could be made a lot more effective through the addition of ingredients like citrulline malate, betaine, and BCAAs, to name just a few. Why would companies not create the most robust formula possible? Because adding more ingredients costs too much money.

Pre JYM includes ingredients that complement one another to prime the body for intense workouts, making it a complete pre-workout supplement. If you're looking for the most complete exercise supplement program available on the market today, take my Post JYM Active Matrix after your workout to get even greater amounts of potent ingredients like Creatine HCl, Betaine, and Beta-Alanine.

No Concentrates

Some companies also try to trick buyers by calling their pre-workout product “concentrated.” A serving of one of these “concentrated” products can contain as few as 3 to 6 grams of powder. What kind of magic did they use to cram enough creatine, beta-alanine, citrulline, arginine, caffeine, and other ingredients into that tiny serving? They didn't use any magic, which is why some of those “concentrated” formulas also include proprietary blends. That's also why the serving size of Pre JYM is more than 26 grams. It contains ingredients at proper, powerful amounts.

JS, Not BS

I've been studying supplement science in the lab and gym for decades. I've been delivering supplement advice to millions of people in the pages of Muscle & Fitness, FLEX, and Muscle & Fitness Hers, as well as here on and my own website,, for over a decade.

Most importantly, I've been training since I was 11 years old. Before each of my workouts, I would draw on all of my experience and all of my education to concoct my own pre-workout supplement, combining ingredients from 13 different bottles and tubs.

That's why I developed Pre JYM. I wanted to give my friends, colleagues, all of you, and myself the ability to access, in one bottle, the best ingredients in amounts suggested to support your fitness goals.

Pre JYM Active Ingredients Matrix Features
  • Full amounts of 13 science-backed ingredients.
  • 6 grams of citrulline malate
  • 6 grams of BCAAs in the 2:1:1 ratio
  • 2 grams of creatine HCl
  • 2 grams of CarnoSyn® beta-alanine
  • 1.5 grams of betaine
  • 600 milligrams of N-acetyl L-cysteine
  • 500 milligrams of Beet Root extract
  • 300 milligrams of caffeine
  • 150 milligrams of AlphaSize® alpha-GPC
  • 5 milligrams of BioPerine®

Under the Microscope

Let's take a closer look some of the ingredients and amounts used to make Pre JYM such a pre-workout powerhouse.*

6 grams of Branched-Chain Amino Acids (BCAAs)
  • The BCAAs are three amino acids—leucine, isoleucine, and valine—that share a common structure.
  • Research suggests that leucine is the most critical because it stimulates muscle protein synthesis.
  • Studies suggest the optimal ratio of leucine to isoleucine to valine in a pre-workout product is 2:1:1, exactly the ratio in Pre JYM.
6 grams of Citrulline Malate
  • In the body, citrulline is readily converted to arginine, and then to nitric oxide (NO). Research suggests that citrulline increases arginine and NO levels in the body better than arginine itself. Arginine undergoes excessive breakdown by the intestines and liver. Studies have shown that citrulline does not, so whatever you consume is readily absorbed and put to use.
2 grams of Creatine HCl
  • Creatine increases physical performance in successive bursts of short-term, high intensity exercise. The beneficial effect is obtained with a daily intake of 3g of creatine.
  • Creatine HCl is made by attaching a hydrochloride (HCl) group to creatine.
2 grams of CarnoSyn® Beta-Alanine
  • Beta-alanine is an amino acid that gets taken up by muscle fibers and combines with the amino acid histidine to form carnosine.
500 mg of Beta Vulgaris L. (Beet) Extract
  • Beet root extract is a rich source of nitrates. When you consume nitrates, they are broken down first to nitrites and then to nitric oxide (NO).
  • Beet root extract is a direct supplier of NO and uses a different pathway to produce NO than citrulline and arginine!
  • Research suggests that nitrates can improve blood flow to working muscles and the brain.* The result is greater training intensity and endurance, and increased focus during workouts.*
1.5 grams of Betaine
  • Betaine, also known as trimethylglycine (TMG), is a modified version of the amino acid glycine.
300mg of AlphaSize® Delivering 150mg of Alpha-Glyceryl phosphoryl choline (Alpha-GPC)
  • Alpha-glyceryl phosphoryl choline (alpha-GPC) is a naturally occurring phospholipid compound.
600mg of N-Acetyl L-Cysteine (NAC)
  • NAC is the amino acid cysteine with an acetyl group attached to it.
300mg of Caffeine
  • Caffeine contributes to an increase in endurance capacity and may help to increase alertness and concentration. Do not exceed a daily intake of 300 mg of caffeine. The beneficial effect is obtained with caffeine consumption at doses of 3 mg/kg body weight at least one hour prior to exercise.
  • 5 mg of BioPerine®
    • BioPerine® is a patented extract of the fruit of black pepper, or long pepper, that contains standardized amounts of the active ingredient piperine.
JYM Supplement Science

Ratings & Reviews

Pre JYM Pre Workout
Overall Rating
4,063 Ratings
Verified Buyer Rating
3,563 Ratings
Average Flavor Rating
10 Flavors
Top Rated Flavor
By clicking the button above, you agree to entering the Reviews section. Products in the Store are not intended to diagnose, treat, cure, or prevent any disease.
Feb 25, 2020
  • 10 Rainbow Sherbet

This is by far my favorite flavor! Just the right amount of sweetness. Been using Jym products for a solid year and I’m very happy with the progress in the gym and on my physique.

Feb 25, 2020
Verified Buyer
  • 10 Refreshing Melon
  • 9 Rainbow Sherbet
  • 8 Raspberry Lemonade

Great product. Very versatile. Can be used as an energy drink, or pre workout. No crazy chemicals that need to be cycled off. It's the closest product to buying individual ingredients and mixing your own variation. Flavor wise I seem to like the less popular Refreshing Melon, originally used Raspberry then Sherbet. Will try other flavors as long as this product does as it says. After years of experience, I have seen a lot of changes in trusted brands. Stack this with other Jym products like Alpha, ZMA, and Shred for quicker and different program results. [Shredding, Bulking, Endurance...]

Feb 21, 2020
Verified Buyer
  • 5 Pineapple Strawberry

It doesn't mix well and the flavor that I had tasted gross. It foams up a lot when shaking.

Feb 21, 2020
  • 7 Cherry Limeade
  • 7 Orange Mango

very good pump but test was not good

Feb 15, 2020
Verified Buyer
  • 10 Raspberry Lemonade

Dr Jim isn’t kidding when he says his pre-w/o has all you need for a stiff kick. You can tell from the portion size alone that it’s packed with all the goodies, with the biggest scoop I’ve seen and the most well rounded panel of ingredients. The flavor is equally strong but it’s pretty good, and mixes well in a 700 ml shaker if you want it during your workout.

Feb 09, 2020
Verified Buyer
  • 10 Cherry Limeade
  • 10 Raspberry Lemonade
  • 10 Black Cherry

Flavor is good, the best part is the level amounts of energy you get, I don’t spike then drop during the workout! I totally would recommend this pre workout!

Feb 04, 2020
  • 1 Rainbow Sherbet

Rainbow sh*t? The taste is HORRIBLE, and I’ve tried nasty supps before. Solid profile though. If you can bare the taste then go for it, but If I have to drink over 15oz of liquid with my pre workout, then I need to look forward to drinking it like Pre Kaged.

Feb 04, 2020
  • 9 Cherry Limeade

just a bit sweet but very hight quality ingredients doesn't harden up like some of the others pre workouts not mentioning any names C4 lol! Jym mixes pretty well gives you a great pump energy and focus.

Feb 01, 2020
Verified Buyer
  • 9 Cherry Limeade
  • 8 Orange Mango

This works great keeps you fuelled during a work out and gain those extra pumps.. first 30-40 minutes you can smash the workout after this it keeps you going for lighter work. Been taking for a while definitely prefer this to prekaged and optimum nutrition gold pre work out.. feels more of a premium product.. this pre work out will still keep you awake so avoid a few hours before bed! For UK deliveries BB need to stick with DPD and not use Hermes for delivery!

Jan 29, 2020
Verified Buyer
  • 10 Refreshing Melon

I've been using Jym products for over 3 years. Best brand out there. Real results. And hands down best flavors. I've tried other brands, nothing compared to the quality and taste of Jym Supplement science

Jan 29, 2020
Verified Buyer
  • 9 Raspberry Lemonade
  • 9 Orange Mango

Best preworkout I have had by far.

Jan 28, 2020
Verified Buyer
  • 9 Pineapple Strawberry
  • 10 Orange Mango
  • 8 Rainbow Sherbet
  • 8 Refreshing Melon
  • 10 Tangerine
  • 7 Black Cherry
  • 8 Raspberry Lemonade
  • 8 Cherry Limeade

Jym products are the real deal! Follow the directions for consumption and enjoy the energy and focus this pre workout brings! Best flavors on the market bar none!

Jan 26, 2020
Verified Buyer
  • 9 Tangerine
Jan 14, 2020
Verified Buyer
  • 10 Cherry Limeade
  • 9 Tangerine
  • 8 Black Cherry

Finally an honest Pre-Workout! No BS ingredients to make me itch, to fool me into think it’s working, it just powers me through a focused session. All the ingredients are on the label, no “proprietary ingredients” or concentrated ingredients that are “equivalent to” bla bla bla like so many other brands. The JYM Supplement Science brand has a loyal customer following because it produces honest unreal results. If you are looking for a brand the works as hard as you do in the gym, the choose JYM.

Jan 08, 2020
Verified Buyer
  • 9 Cherry Limeade

Definitely the best pre-workout supplement I've ever had! I use it for the gym but also for pepping me up before a night shift etc as I honestly believes it seems to improve physical and cognitive performance - possibly via the caffeine but I used to use Fury Extreme which had even more caffeine though I didn't feel this good on that. The taste is very good too! Slight negative is I occasionally notice my lips + tongue going a bit red afterwards which can take a bit of explaining to colleagues etc. I'm a little unclear why it's this good but I'll certainly be a repeat customer!

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Price: £39.99  (£1.33 / Serving)
Flavor Rating: 8.5
Pre Workout with High Quality Ingredients

What's in JYM Supplement Science Pre JYM Pre Workout

Serving Size: 1 Scoop (26g)
Servings Per Container30
Per 26g Portion % Reference Intake
Energy (KJ) 335 kJ 15%*
Energy (kcal) 80 kcal       
Carbohydrate 3 g 1%*
Of Which Sugars 2 g **
Salt (As Sodium Chloride) 240 mg 4%*
Citrulline Malate 6 g **
L-Leucine 3 g **
L-Isoleucine 1.5 g **
L-Valine 1.5 g **
Creatine HCI (as CON-CRET®) 2 g **
Beta-Alanine (CarnoSyn®) 2 g **
Betaine (Trimethylglycine) 1.5 g **
L-Tyrosine 1.5 g **
Taurine 1 g **
Beet (Beta vulgaris) Root Extract 500 mg **
Choline Bitartrate 350 mg **
Caffeine Anhydrous 300 mg **
Alpha-Glyceryl Phosphoryl Choline (as AlphaSize®) 150 mg **
N-Acetyl L-Cysteine 100 mg **
Black Pepper (Piper nigrum) Fruit Extract (as BioPerine®) 5 mg **
* Reference Intake of an average adult (8400kJ/2000 kcal).
** Reference Intakes not established.
Other Ingredients:
Citrulline Malate, L-Leucine, Creatine Hydrochloride (as CON-CRET®), Beta-Alanine (as CarnoSyn®), Dextrose, L-Isoleucine, L-Valine, L-Tyrosine, Betaine (Trimethylglycine), Taurine, Sodium (as Disodium Phosphate), Sweeteners (Sucralose, Acesulfame Potassium), Flavouring, Beet (Beta vulgaris) Root Extract, Choline Bitartrate, Caffeine Anhydrous, Alpha-Glyceryl Phosphoryl Choline (as AlphaSize®), N-Acetyl L-Cysteine, Stabilisers (Cellulose Gum, Xanthan Gum, Carrageenan), Colour (Allura Red AC), Black Pepper (Piper nigrum) Fruit Extract (as BioPerine®).
For allergens, see ingredients in bold. Produced on shared equipment that also produces products that may contain EGG, MILK, SOYA, TREE NUTS, WHEAT.

Directions For Pre JYM Pre Workout: As a Food Supplement, mix 1 scoop of Pre JYM™ in 400 to 1000 mL of water and drink 30-45 minutes before workouts. Consider allowing Pre JYM to mix for 10-15 minutes before drinking. Also consider drinking it over the course of 15-30 minutes. Initially use 1/2 serving or less to assess tolerance. Once tolerance is assessed, take no more than 1 serving. To avoid sleeplessness, do not consume within 6 hours of bedtime.


Flavoured Food Supplement Powder with Amino Acids, Caffeine and Sweeteners

DO NOT USE IF YOU ARE UNDER THE AGE OF 18, PREGNANT OR NURSING, HAVE ANY KNOWN OR SUSPECTED MEDICAL CONDITIONS, ARE TAKING ANY PRESCRIPTION OR OVER THE COUNTER MEDICATIONS, OR SENSITIVE TO CAFFEINE. Consult with a qualified healthcare professional before using this or any other food supplement. Contains 300mg of caffeine per serving, the equivalent of approximately 3 cups of coffee. DO NOT USE WITH ANY OTHER CAFFEINATED PRODUCT. Too much caffeine may cause nervousness, irritability, sleeplessness and/or rapid heartbeat. Immediately discontinue use and consult your doctor if any adverse reactions occur.

Allura Red AC and Tartrazine may have an adverse effect on activity and attention in children. Do not exceed the recommended daily amount. This product should not be used as a substitute for a varied diet or a healthy lifestyle. KEEP OUT OF REACH OF CHILDREN

Manufactured in the US for: (UK) Ltd. Units 7-8 Foster Avenue Dunstable, Bedfordshire, LU5 5TA.

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