JYM Supplement Science


Food Supplement
Pre Workout with High Quality Ingredients
9.1  out of 10  (3,942 Reviews)

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
3,942 Ratings
Verified Buyer Rating
3,467 Ratings
Average Flavor Rating
9 Flavors
Top Rated Flavor
Raspberry Lemonade
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.
Mar 24, 2019
Verified Buyer
  • 1 Rainbow Sherbet

Do I feel pumped after this for a workout? Yes Does the rainbow sherbet taste like the insides of a unicorn? Also yes. Recommend trying a different flavor.

Mar 20, 2019
Verified Buyer
  • 10 Cherry Limeade
  • 6 Black Cherry
  • 10 Rainbow Sherbet

Great preworkout but definitely don't recommend taking later in the day if you already have insomnia issues. Steady flow of energy/ focus without a huge crash, as a student I really appreciate the lasting effects to study after my workouts without feeling jittery. I havent had any stomach issues with this product. Some other products have caused an itchy/ tingly sensation, I haven't had that issue with pre jym. Great product for maximizing your workout pushing past physical and mental blocks. I think some people underestimate that a preworkout helps with more than just muscles but also with your brain! The sweetness of the product is kind of like candy without being grossly sweet, which helps curb other sweet cravings throughout the day. Cherry Limeade tastes a lot like the Cherry Limeade minute made flavor you can try at the Coca-Cola free style dispensers. It is a bold/ robust/ strong flavor. I'd like to try other flavors but been a bit hesitant to stray away from something I know I already love. The Rainbow Sherbet is a lighter flavor, still sweet without that punch like the other 2. I only tried a sample pack once or twice but it seemed like you could taste the aminos just slightly more than in post jym of the same flavor. The cheap little sorbet cups a lot of us had as a kid would be a good reference for the taste except it tastes a little more subtle than that and also no dairy. I tried the Black Cherry flavor once because the Cherry Limeade was out of stock. I figured they'd be very similar but I was wrong. The Black Cherry tastes more artificial in my opinion, kind of like a Cherry Kool-aid. If my favorite flavor (Cherry Limeade) goes out of stock I'll try a different flavor over this one. This one is also a strong flavor.

Mar 20, 2019
Verified Buyer
  • 7 Cherry Limeade
  • 7 Raspberry Lemonade

Overall a top pre workout. Gave it a 9 because it messes with my stomach a little bit and isn’t the best pre wo I’ve had. I would still recommend.

Mar 16, 2019
Verified Buyer
  • 10 Orange Mango

I’ve tried a lot of pre’s and this is the best! No jitters, no crash. Body feels awake for a great workout.

Mar 14, 2019
Verified Buyer
  • 9 Black Cherry
  • 8 Cherry Limeade

Love this product. It gives me a little extra boost during my workout like no other product has done in the past. I am 60 years old and need that boost to make through each workout. The only issue I have with it is the sweetness. I do believe they could tone that down a bit.

Mar 12, 2019
  • 10 Black Cherry

This is the best pre workout hands down. Clinically dosed and backed by science to give you the correct doses of nutrients needed for every workout. Transparent label and no lies! Ever since I switched to jym’s supplements, I have seen greater results in my performance, strength, and overall mental focus. I highly recommend this pre workout and the whole Jym line!

Mar 11, 2019
Verified Buyer
  • 1 Orange Mango

Awful taste! This is one of the worst tasting pre-workouts I've tried. It does however give you a good start to your workout. If a good sweat is your goal this product will hit the mark.

Mar 07, 2019
Verified Buyer
  • 10 Rainbow Sherbet

I was introduced to Jym products by reading reviews and Jim Sotppani's videos and thought why not. I am so glad I did. I will never go with another pre-workout then Jym's. I workout at 4 am in the morning, and I swear there are times, I am so weak at that hour that lifting the metal Shaker cup I use to mix my pre-workout hurts and weighs like a ton of bricks. Then I take my first sip, and you can almost instantly feel the ingredients enter your system, and get to work. By the time I get to the gym usualy about 30 minutes after drinking my pre, I am ready and in beast mode..Thank You Jym.. As far as tatse, I've only ever tried the Rainbow Sherbert. I like sweet drinks, and to me this is perfectly made. Good flavor, and just the right amount of sweetness. Results- I look the best Ive ever looked right now, and that is in part to Jym supplements and diet. Give all Jym products a try I think you will agree noone makes a better product, you might like something else, but it wont be better. That I can promise you...

Mar 07, 2019
Verified Buyer
  • 10 Raspberry Lemonade

Best product hands down. Absolutely makes all the difference in my workouts, not to mention great taste. I have tried other products but this Jym takes the prize

Mar 04, 2019
Verified Buyer
  • 6 Cherry Limeade

Nice product, does the job but I don’t like the caffeine and I don’t know why Jim keeps adding the gum thing everywhere!!! It’s nice pre work out, but please get rid of the non sense gum and cellulose sugary thing and all sugar alternatives names. I tried it and it kind of strong in my stomach

Mar 03, 2019
Verified Buyer
  • 10 Raspberry Lemonade
  • 9 Strawberry Kiwi
  • 9 Orange Mango

You can't really go wrong with any pre jym, I've yet to find a flavor that I didn't like... but there are a few that stand out above the rest!! Amazing taste, amazing results! Win/ win! Wouldn't use any other brand!!

Mar 03, 2019
Verified Buyer
  • 10 Black Cherry

This is probably the best Pre work out I have taken. Ramps up nice sustaining a nice amount of energy for a grueling work out and comes down smooth. Im not into the niacin tingle anymore.

Mar 03, 2019
  • 3 Black Cherry

After taking this, I get a lot of flatulence shortly after. And I've read through the forums and seen that I'm not the only one this happens to. I don't know what it is, but it's a pain to deal with during my workout

Mar 02, 2019
  • 10 Raspberry Lemonade
  • 10 Rainbow Sherbet

Simply the best!!! Great energy, great focus, great strength...amazing taste...mixes crash after!!! Seriously...can u beat this, no!... my results speak for themselves!!!

Feb 26, 2019
Verified Buyer
  • 5 Pineapple Strawberry
  • 10 Cherry Limeade

Pineapple strawberry is alright but nothing beats the cherry limeade. Cherry limeade is by far the best product!

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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