JYM Supplement Science


Food Supplement
Pre Workout with High Quality Ingredients
9.1  out of 10  (3,961 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

Overall Rating
3,961 Ratings
Verified Buyer Rating
3,482 Ratings
Average Flavor Rating
10 Flavors
Top Rated Flavor
Cherry Limeade
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.
May 20, 2019
Verified Buyer
  • 8 Tangerine

This flavor certainly taste like a tangerine. It is not as sweet as Orange Mango and not as tart or sour as Pink Lemonade. It has a refreshing taste to it and is well-suited for a morning workout pre-workout drink. No matter the flavor, this is still the best pre-workout I have used and I have not used any other pre-workout since Cherry Limeade was the first flavor released years ago.

May 20, 2019
Verified Buyer
  • 10 Orange Mango
  • 10 Pineapple Strawberry
  • 9 Rainbow Sherbet
  • 9 Refreshing Melon

The best pre workout on the market, with the perfect dosing of everything you need, when you pair it with the post workout. Orange Mango has to be the best flavor I have ever tried, and the wife and kids love it too!

May 18, 2019
Verified Buyer
  • 10 Orange Mango
  • 7 Cherry Limeade

Amazing pre-workout with the correct doses of critical ingredients needed to supplement your training. The Orange Mango flavor is by far one of the best supplement flavors I've ever had. The Cherry Limeade is also good, but the Orange Mango is certainly a cut above! I also use: PostJym, VitaJym, OmegaJym, ZMAJym, ShredJym, and ProJym.

May 17, 2019
Verified Buyer
  • 7 Tangerine

Tangerine is a pretty decent flavor. It tastes like a tangerine, it's tart, and not too sweet. Orange Mango is definitely better. Leaves a weird feeling in the back of my throat. As far as effectiveness, Pre Jym is solid.

May 16, 2019
Verified Buyer
  • 10 Orange Mango
  • 6 Tangerine
  • 10 Rainbow Sherbet
  • 9 Raspberry Lemonade

Best preworkout on the market. Never had a flavor I didn't like but my two favorites are Orange Mango and Rainbow Sherbet

May 10, 2019
Verified Buyer
  • 9 Raspberry Lemonade

Second best flavor....perfect for summer time

May 10, 2019
Verified Buyer
  • 6 Black Cherry
  • 9 Cherry Limeade
  • 9 Orange Mango
  • 8 Pineapple Strawberry
  • 7 Rainbow Sherbet
  • 9 Raspberry Lemonade
  • 5 Refreshing Melon
  • 5 Strawberry Kiwi
  • 9 Tangerine

Best pre work out on the market. Transparent label so you know exactly what you’re getting. Saves you money so you don’t have to purchase separate products such as creative and bcaas since they’re already in there. Can’t go wrong with any of the 3 legacy flavors (orange mango cherry limeade and raspberry lemonade). Just tried tangerine the other day and that flavor is super smooth and tastes great as well.

May 09, 2019
  • 1 Black Cherry

Although the preworkout does what it's supposed to, I didn't notice anything that stood out over most others. My two main gripes about this Pre is the scoop size and the taste. I usually take my pre as a shot with about 4-5 Oz of water because I hate the bloat feeling that comes with downing a full shaker before a workout and this scoop size is gigantic, the 4 Oz of water I normally use with this one single serving made it into a paste; adding the recommended water is just too much for me and it's my mistake for not reading the info beforehand. I also should've paid attention to the flavor ratings because this Black Cherry was quite possible the worst flavor I've ever tasted in a supplement. I know it sounds like an exaggeration but I just couldn't bear it, I had to brush my teeth after because of the lingering smell/after-taste and now I'm wondering what to do with this brand new tub of pre that I'll never use again

May 09, 2019
Verified Buyer
  • 9 Tangerine
  • 10 Orange Mango
  • 9 Cherry Limeade
  • 9 Raspberry Lemonade
  • 9 Pineapple Strawberry
  • 9 Rainbow Sherbet
  • 7 Black Cherry
  • 7 Refreshing Melon
  • 8 Strawberry Kiwi

I have been using all of the JYM products for at least 4 years. I absolutely love Pre JYM and the new Tangerine flavor is incredible, I put it up there with orange mango flavor. Even if they didn’t have amazing tasting pre workouts I would still take them. I know how I feel and perform when taking Pre JYM & JYM products. I get up very early for work and also use Pre JYM during the day as an energy drink.

May 06, 2019
Verified Buyer
  • 1 Pineapple Strawberry
  • 5 Rainbow Sherbet

Works great. Does give a tingle. Serving size is larger than most other PWO. Pineapple Strawberry was terrible, I couldn't get it down. Rainbow Sherbet is OK but probably wouldn't order that flavor again.

May 05, 2019
Verified Buyer
  • 10 Rainbow Sherbet

Best pre workout on the market! Incredible pump. Amazing taste. I found my product for years to come!

May 04, 2019
Verified Buyer
  • 1 Black Cherry

Firstly I will admit I was a long time user of Jack3d so I find it really hard to find a good pre workout. I was very hopeful about the Jym pre workout based on the reviews but was very disappointed. It had zero effect on my workout. No pump no increased energy etc. The scoop is huge and the amount of water recommended way to much to drink before a workout and the instructions of drinking it over 15mins and an hour before exercise!? Seriously! The Cherry flavor was sickly sweet and the product as a whole left me bloated and feeling sick. I would be burping it up throughout my workout making sit ups and cardio impossible. I gave it the benefit of the doubt and used it a few times to see if I got use to it but saw no improvement so I had to give up on it.

Apr 26, 2019
  • 10 Orange Mango
  • 9 Cherry Limeade
  • 10 Pineapple Strawberry

I’ve had 3 flavors so far all are amazing! I’d say the orange mango still holds the crown though. Love this product

Apr 25, 2019
Verified Buyer
  • 10 Orange Mango
Apr 23, 2019
  • 9 Orange Mango

I started taking pre jym for the first time about a month ago or so. And once I’m home my mouth always starts to salivate and I start feeling nauseous. Anyone else feel that way? I don’t that feel like that at the gym. It’s always once I’m done working out. Any feedback would be great, thanks!

1 Size
30 Servings
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3 Flavors
Cherry Limeade
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Price: £39.99  (£1.33 / Serving)
Flavor Rating: 8.5

What's in JYM Supplement Science Pre JYM

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: 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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