T2. Aliens. Big Momma’s House 2.

All represent rare instances of sequels which don’t suck.

OK. Maybe not that last one.

But when we’re talking supplements, sequels are usually a poor imitation of the original, thrown together when an ingredient gets flagged up or banned.

Which brings us to Pre Jym 2.0, the brand new pre workout from Dr. Jim Stoppani.

pre jym review


I can’t give you a Pre Jym review without first giving you the backstory behind why there’s even a new version of Pre Jym out there to begin with.

So, in case you don’t keep up to date with fitness industry shenanigans, Jim originally launched his Jym Supplement Science line with, and it quickly became the biggest-selling pre workout in the world.

That’s thanks largely to it’s solid formula (which we’ll get to), a transparent label, and the level of trust Jim Stoppani has built up within the supplement industry after years of solid advice in muscle building magazines and bodybuilding websites.

But things didn’t stay perfect for long…

By the end of 2016, Jim and had parted ways after a disagreement over who actually owned the Jym supplement brand, and Stoppani wound up releasing a whole new line-up through GNC (hence we have Pre Jym 2.0).

To make matters doubly confusing for the customer, stuck to their guns and carried on selling the original Jym supplements, so we really had two different versions of the same product on the market for a while!

Unfortunately, Jim lost some of his credibility during this time after a series of rants towards other supplement companies. Most notably, this one with NutraBio founder Mark Glazer, and this debacle in which Jim claimed his supplements are the only ones on the market which don’t use a proprietary blend.

(They are not, nor were they the first.)

Thankfully, after the continued success of Pre Jym via distribution through GNC, the two parties managed to patch up their relationship and Jim returned “home” to in mid-2017, where they continue to sell the new and improved Pre Jym formula.

Now you’re up to speed!


It’s very important to know the information above when trying the new Pre Jym.

Because despite the brand change, the drama, and the snazzy new label design, what we see here is an almost identical formula to the original.

While the 2.0 suggests a “next generation” of Jym supplements, this is merely clever marketing. Once we get under the hood of the product, we are getting the same old same old, with the name merely altered to separate this product – and proclaim superiority – from confusion with the old Jym brand that was also being sold separately at the time through bodybuilding,com.

Make sense?

In fact, the only notable difference between the new formula and the old formula is the inclusion of huperzine-A in the new blend.

Huperzine-A is a nootropic alkaloid which is added to bodybuilding supplements to increase mental focus, although no significant research exists to document it’s effectiveness at doing so. It has, however, been shown to increase muscle contraction force, so that’s something. (1)

Is huperzine-A going to make or break your workout? Absolutely not!

Thankfully, the rest of the Pre Jym formula still stands up, meaning it is able to hold it’s own at the top end of the premium pre workout supplement market.

A full clinical dose of 6g citrulline malate will provide you with enhanced training endurance, improved recovery between sets and a great pump. Couple this with a 2 gram serving of beta-alanine to delay the onset of lactic acid, and you should see some rather impressive boosts to workout performance with Pre Jym. (3, 4)

The real powerhouse of most pre workout supplements (and this is no different) is caffeine. At 300mg per serving, Pre Jym is near the top end of the supplement market in terms of dosage.

Finally, open label transparency continues with the entire Jym Supplement Science brand, so there are no hidden ingredients or misleading proprietary blends on display here. That’s a great thing.

pre jym 2.0 review


Nothing is perfect.

Not even the self-proclaimed “king.”

So where does Pre Jym get it wrong? And where could it be better?

Well, first up we have the inclusion of creatine HCL.

There is nothing wrong with creatine in general (and creatine HCL shows promise as an alternative to creatine monohydrate) however it offers no additional benefits to consume creatine prior to training versus just staying on top of your daily intake. Seeing as it’s very cheap to supplement with creatine anyway, this ingredient is somewhat unnecessary as part of a pre.

You could argue that beta-alanine is under-dosed in Pre Jym. At 2 grams per serving, this falls well short of the recommended 3.2g clinical dose.

However, research suggests that you can enhance absorption (slightly) by splitting beta-alanine consumption into two as opposed to taking it all in one serving, and it’s worth noting that Stoppani also offers another 2g serving (totally 4g) in his post-workout supplement, Post Jym. (9)

Like most other pre workouts, Pre Jym comes equipped with a 1g serving of taurine in each scoop. This is a big negative, as taurine is a proven antagonist of caffeine, and given the large serving of caffeine on offer here it doesn’t make sense to dilute it by putting taurine alongside it.

The inclusion of leucine is a controversial one.

It’s long been thought to boost training performance when taken as part of a pre workout, which is why you can often see BCAAs included in formulas. However, interesting research suggests that leucine is best kept until after training, as it can lead to CNS fatigue and cause the trainee to feel sluggish. (7, 8)

pre jym review


Let’s take a more in-depth look at the ingredients inside Pre Jym to see whether it contains enough of each key ingredient to give you the expected training results.

The pre workout marketplace is rife with below-par products which hide their formula behind bogus proprietary blends or under-dose key ingredients, leaving you feeling ripped off.

For the most part, you should be pleasantly surprised by Pre Jym.



Caffeine is the star player in any great pre workout, and Pre Jym doesn’t skimp on the dosage here.

The effectiveness of caffeine is dependent on an individual’s tolerance level, but 300mg per serving puts this right at the top end of the spectrum and means that this product is most certainly a one-scooper, unless you plan on laying in bed like a pneumatic drill. (2)

Most people know caffeine for its energy boosting properties, which have been well documented in various studies over the years, but it’s also been shown to boost mental focus and can even boost strength output if taken in very high dosages.

The fat burning benefits are overstated, but the mental boost and energy kick are more than enough to warrant its position as a valuable pre workout ingredient.

pre jym 2.0 review


Citrulline malate is the most under-appreciated ingredient in a truly great pre workout supplement.

While we like to focus on the ingredients we can feel working (caffeine and beta-alanine), citrulline gets to work in the background and when supplemented regularly it can make a huge difference to the quality of your training!

Six grams is the clinically proven dosage at which we can expect to see the maximum response, so Pre Jym hits the mark here.

This post will tell you more about citrulline malate.



Have you ever felt your face tingling after drinking a preworkout?

That’s beta-alanine.

But while it’s often unfairly used as a superficial ingredient which is thrown in purely so you can ‘feel’ your pre kicking in, there are numerous benefits to using beta-alanine.

A 2010 study from researchers at the University of Manchester discovered that boxers increased their punching power by as much as 2000% during the closing stages of a bout via supplementing with beta-alanine prior to training. (5)

It is also useful for improving your ability to push through “the burn” during training, with another useful study showing us that subjects were able to force out 25% more repetitions per set. (6)



There are 6 grams of BCAAs included in each serving of Pre Jym.

That’s broken down as 3g leucine, 1.5g isoleucine, and 1.5g valine.

BCAAs are often referred to as “the building blocks of muscle” due to their anabolic capabilities, so it’s no surprise to see them in so many pre workout formulas from most of the leading brands.

However, that doesn’t mean it’s right.

You may have noticed that I listed this as a red flag above. That’s because research suggests that when leucine is taken pre workout it acts as an inhibitor of l-tyrosine, preventing dopamine production and even making the user feel sluggish during training.

Taking BCAAs before training is one of those popular fitness beliefs which makes sense in theory but doesn’t work in practice, and it needs to be thrown on the scrapheap, like the fasted cardio BCAA myth.

Jim Stoppani Pre Jym review


Creatine is incredible for boosting strength performance and muscle size.

It’s probably the most well-researched bodybuilding supplement of all time, with decades of solid evidence to support it’s benefits and safety. (10)

That said, the inclusion of creatine HCL is an odd choice. Jim insists it’s because this blend is superior to the original form (creatine monohydrate), but this has never been shown in any studies.

Given that Pre Jym’s whole gimmick is that it’s build upon solid science, it would’ve made perfect sense to opt for creatine monohydrate.

However, Creatine HCL should be able to provide similar results as monohydrate, and it can be done with a smaller dose (2g instead of 5g). (11)


Taurine is the darling of the pre workout and energy drink industry.

That’s because it’s a very cheap ingredient, and has been shown to have positive effects on mental focus and increased blood flow to working muscles. (12, 13)

However, we’d need a dose of 2g to see any of those benefits, so Pre Jym is under-dosed here and you’d have to either pick up more taurine or order Post Jym to get the rest.

But the bigger issue with this ingredient is that taurine is an antagonist of caffeine.

This means it blocks the effectiveness of The Big C when they are consumed directly, as was shown in a 2012 study published in Pharmacology, Biochemistry & Behaviour. (14)

This was a huge talking point when AML released their excellent pre workout (the imaginatively titled AML Pre Workout) in 2016 and directly called out the Jym brand for their inclusion of both taurine and leucine.


This amino acid is a precursor to dopamine.

A 2011 study published in the Journal of Applied Physiology showed that it’s possible to increase training capacity by using l-tyrosine to increase dopamine production, as subjects performed markedly better during exercise in outdoor heat. (15)

Including it alongside caffeine (and a hefty serving size to boot!) will result in a decent energy boost before training, but it’s held back by being consumed alongside leucine in Pre Jym, as explained above.

pre jym 2 vs pre jym original


There will be two groups of people looking at Pre Jym 2.0.

  1. Those looking for a great pre workout.
  2. Those trying to figure out what the difference is between this and the old Pre Jym supplement.

If you fall into the first group, you will find Pre Jym to be a great pre workout supplement.

I’ve always been a big fan of the doctor and the work he has done in the supplement industry over the years. This product lives up to its billing as one of the very top pre workout supplements in its class.

In true Jim Stoppani style, the dosages for MOST key ingredients have been clinically proven to increase workout performance, and the label is very transparent.

However, it’s no longer considered “the king of pre workouts”.

Since the release of Pre Jym, an array of other trustworthy supplement manufacturers have raised their game, and it will be interesting to see if we ever get another version of Pre Jym to compete with the innovations which have taken place in the last couple of years, most notably the fantastic product released by Advanced Molecular Labs.

If you’re a user of the original Pre Jym, you are really not missing anything “new and improved” here other than maybe the packaging. If you like green.

As such, my Pre Jym review concludes with the award of 4 stars from my deliberately harsh supplement rating system. The fabled 5 stars is lost due to the inclusion of BCAAs, taurine, and the fact that I’m still a bit p****d the name hinted at a new and improved formula.

To get the absolute best deal on Pre Jym, order from here for the UK and here for the USA.

I also highly recommend trying RedCon1 Total War and AML Pre Workout. Total War is basically a cut price version of Pre Jym, whereas AML Pre Workout is a superior version of it.

Pre Jym review

Online Workouts Programs


  1. Tang, Xi Can, et al. Pharmacological profile of huperzine A, a novel acetylcholinesterase inhibitor from Chinese herb. CNS Drug Reviews 5.3. (1999)
  2. Beaven, C. M., et al. Dose effect of caffeine on testosterone and cortisol responses to resistance exercise. Int J Sport Nutr Exerc Metab. (2008)
  3. Pérez-Guisado, J., et al. Citrulline malate enhances athletic anaerobic performance and relieves muscle soreness. J Strength Cond Res. (2010)
  4. Alvares, T. S., et al. Acute l-arginine supplementation increases muscle blood volume but not strength performance. Appl Physiol Nutr Metab. (2012)
  5. Donovan, T., et al. Beta-alanine improves punch force and frequency in amateur boxers during a simulated contest. Int J Sport Nutr Exerc Metab. (2012)
  6. Hoffman, J., et al. Beta-alanine and the hormonal response to exercise. Int J Sports Med. (2008)
  7. Walker, D.K., et al. Exercise, amino acids, and aging in the control of human muscle protein synthesis. Med Sci Sports Exerc. (2011)
  8. Choi, S., et al. Oral branched-chain amino acid supplements that reduce brain serotonin during exercise in rats also lower brain catecholamines. Amino Acids. (2013)
  9. Artioli, G. G., et al. Role of beta-alanine supplementation on muscle carnosine and exercise performance. Med Sci Sports Exerc. (2010)
  10. Rawson, E.S., et al. Effects of creatine supplementation and resistance training on muscle strength and weightlifting performance. J Strength Cond Res. (2003)
  11. Green, A. L., et al. Carbohydrate ingestion augments skeletal muscle creatine accumulation during creatine supplementation in humans. Am J Physiol. (1996)
  12. Kim, S., et al. Taurine Induces Anti-Anxiety by Activating Strychnine-Sensitive Glycine Receptor in Vivo. Annals of Nutrition and Metabolism. (2009)
  13. Moloney, M. A., et al. Two weeks taurine supplementation reverses endothelial dysfunction in young male type 1 diabetics. Diab Vasc Dis Res. (2010)
  14. Giles, G. E., et al. Differential cognitive effects of energy drink ingredients: caffeine, taurine, and glucose. Pharmacol Biochem Behav. (2012)
  15. Tumilty, L., et al. Oral tyrosine supplementation improves exercise capacity in the heat. Eur J Appl Physiol. (2011)


  1. Justin Newman @ Shapesanity says:

    I’ve been using Pre Jym for about a month it’s been great. I’ve been adding creatine to the mix and have seen pretty decent gains in strength.

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