Transparent Labs PreSeries BULK Pre-Workout Review

PreSeries Bulk Review

With all the low-quality and "proprietary mix" pre-workouts on the market, it's always refreshing to review a supplement with a transparent ingredients list and great doses. As you'll soon find out, PreSeries BULK by Transparent Labs is a great example of this.

How does BULK compare to other pre-workouts on the market though? And does it provide value for money? Keep reading our review to find out.

Basic Overview of PreSeries BULK

PreSeries BULK pre-workout has been designed to help boost the production of lean muscle mass. Transparent Labs describes it as the "most exceptional bulking pre-workout supplement available," due to its combination of clinically effective doses, wide range of ingredients and testosterone support complex.

You'll notice that BULK is relatively light on stimulants. It only contains 180mg of caffeine, which is significantly lower than the 350mg+ found in other pre-workouts for bodybuilding.

While some people may miss the intense buzz of extra caffeine, this shows Transparent Labs has confidence in the effectiveness of their product. Brands often pump up the caffeine dose to mask the lack of other active ingredients.

Even with the small dose of stimulants, each serving is a huge 22g - and the vast majority is active ingredients. This certainly isn't a pre-workout that's mainly filler and caffeine.

Aside from helping you bulk up, the pre workout is also designed to:

  • Enhance Performance. BULK isn't just for getting big. It has a balanced ingredient profile that can enhance endurance and strength too.
  • Reduce Fatigue. The longer and harder you can work out, the more lean muscle mass you'll build. BULK helps reduce fatigue so you can push through grueling workouts.
  • Increase Muscle Pump and Fullness. Several ingredients in BULK increase nitric oxide production. This dilates blood vessels and leads to fuller muscles with a noticeably enhanced pump. If you're interested in learning more about the best pre workouts for pump, check out our page here:
  • Minimize Muscle Soreness. Sore muscles can reduce performance in your next workout. BULK is designed to minimize soreness while protecting muscle fibers.

Ingredients Profile

List of ingredients and nutrition facts

We've already mentioned that BULK doesn't contain proprietary blends or hidden ingredient profiles. It also doesn't contain any artificial colorings, preservatives or sweeteners. It's debatable how harmful artificial additives actually are, but it's best to avoid them if you can.

Transparent Labs has also included important ingredients at a clinically effective level. This is vital if you want a pre workout supplement to provide the maximum benefit.

Unlike stripped-back pre-workouts, like Legion Pulse (see here for our review), BULK contains a huge 19 active ingredients. We're usually not fans of long ingredient lists, as they often mean the manufacturer has to reduce doses. Fortunately, this doesn't seem to have happened with BULK.

Here's a run-down of some of the most important ingredients and doses:

  • Citrulline Malate (6000mg). Citrulline is one of the most important ingredients in a modern preworkout supplement. It's been shown to enhance strength, endurance and aerobic performance, while increasing blood flow for a great pump. BULK contains 6000mg citrulline per serving, which is within the clinically-backed range to get these benefits. 
  • Beta-Alanine (4000mg). Beta-Alanine is an amino acid that delays fatigue during intense exercise. This means you can work out harder and for longer, which may trigger the formation of more lean muscle mass. Many pre workouts are hugely underdosed with Beta-Alanine, but this isn't the case with BULK.
  • BCAAs (4000mg). The benefits of BCAAs might be overstated, but there's no doubt that leucine, in particular, can increase strength during workouts if you don't get enough in your diet. BULK contains 4g of BCAAs in a 2:1:1 ratio. The inclusion of BCAAs is particularly useful for fasted training.
  • Betaine (2500mg). Betaine can have a significant effect on fatigue, strength and endurance if taken before a gym session. It may also trigger the formation of more lean muscle mass. The clinically-effective dose of betaine is 1500mg-2500mg, so BULK contains a generous amount per serving.
  • Taurine (1300mg). Supplementing taurine may be important if you're regularly taking beta-alanine, which is the main reason it's included in BULK. It may also reduce post-workout soreness.
  • N-Acetyl L-Tyrosine (600mg). This amino acid is part of BULK's focus and energy complex. It helps improve focus, endurance and memory, so you can push out a few more reps at the end of your workout.
  • Caffeine & L-Theanine (180mg & 360mg). As we mentioned earlier, BULK is relatively light on stimulants. 180mg of caffeine per serving is around half that of many pre-workouts for weight lifting. With that said, the combination of caffeine and L-theanine, along with the relatively light dose, means it provides a fast boost to energy without jitters or loss of coordination. It's also less likely to keep you up at night if you take it in the late afternoon.
  • Synephrine (50mg). Supplementing synephrine can raise your metabolic rate, which allows you to burn more calories and fat. While it won't have a huge effect, it can help burn some excess calories during a bulking phase.
  • Testosterone Support Complex. As PreSeries BULK is designed for athletes undergoing a bulking phase, it includes several extra nutrients that support healthy testosterone levels. These are vitamin D3, Boron and Zinc. It's worth noting that these supplements only support your body's natural production of testosterone, so it's also safe for women.

Aside from the primary ingredients above, Transparent Labs has included several others.

The first is Mucuna Pruriens. This may enhance your psychological state during a workout, although the effect is likely to be subtle if felt at all. More importantly, Mucuna Pruriens may boost healthy testosterone levels and lead to the production of more growth hormone.

Other ingredients include L-Norvaline, which may boost Nitric Oxide production, and Bioperine which helps the absorption of other supplements. While these extra ingredients won't have a big effect on your workout (at least in comparison to the main ingredients), they are unlikely to do any harm either.

We are very impressed by the ingredients profile of PreSeries BULK pre-workout. The most important ingredients are all included at clinically-effective doses, so you know you're getting the full benefit of each. The lower stimulant dose also reduces the chance of crashes and leads to a cleaner, more reliable boost in performance.

On a side note, the only ingredient that contains carbs is the BCAAs. This means a single serving contains approximately 16 calories. Keep this in mind if you are on a fasted or keto diet.

What About Creatine?

Pre-Series BULK is a creatine-free pre-workout supplement. Considering creatine is one of the few proven supplements to enhance muscle growth, this might seem like a strange choice.

The reason creatine isn't included is because there is some evidence it's not as effective when taken with caffeine. For this reason, Transparent Labs recommends supplementing creatine at a different time to your pre-workout.

It's worth mentioning that there is conflicting evidence as to whether caffeine actually interferes with the effects of caffeine. Even so, we can see why it hasn't been included.

Taste & Mixability

The Pure Sieries BULK preworkout is designed for bodybuilders

One of the biggest drawbacks of PreSeries BULK pre workout is the flavor. It's not disgusting, but it's not particularly pleasant to drink either.

There are several flavors though, so you can test it to see which you like best. Our favorite is strawberry lemonade, but there are also green apple and blue raspberry options.

As you would expect from a pre workout supplement that contains a large dose of citrulline, there is some foaming when you mix it. This doesn't seem to be as bad as some of our other reviews though.

Other than the foaming, BULK mixes well so you shouldn't have to deal with lots of powder or sediment at the bottom.


A standard container of Pre Series BULK contains 30 servings of one scoop each. You don't need to double scoop it, as a single serving contains clinically effective doses of all the main ingredients.

It's a good idea to start with half a scoop mixed with 8-12 fl. oz of water. This is to assess your tolerance levels. When/if you want to take a full scoop, increase the amount of mixing water to 16-24 fl. oz.

Transparent Labs recommends taking BULK 20-30 minutes before your workout.

How Effective Is BULK Pre Workout?

The Pro Series BULK pre workout is great for building lean muscle

We think PreSeries BULK is an excellent preworkout supplement if you want to gain lean muscle mass while enhancing your all-round performance. BULK is also one of the best options if you don't want to be overloaded with stimulants, but would still like caffeine and L-Theanine to be included.

Unlike cheaper alternatives, BULK is great for providing a clean and sustained enhancement in your workout, without the inevitable crash. It doesn't just provide a cheap caffeine hit, but instead includes a variety of scientifically-backed ingredients to improve your workout.

Where BULK really shines is its ability to enhance your endurance. The beta-alanine and betaine, in particular, allow you to push through your workout with more reps and sets.

Additionally, Pre Series BULK increases your focus during a workout. It also provides a mental alertness and clarity that helps you get into the zone.

One thing to keep in mind is that it won't provide the harsh boost associated pre-workouts that are loaded with stimulants. You probably won't get that hyped-up feeling either. It'll still provide a noticeable increase in energy though - and without the negative side effects of excessive stimulants.

A bonus is that it can provide great vascularity and pump. This is due to the nitric oxide production caused by the large 6g dose of citrulline.

In short, we don't think you'll be disappointed by BULK's results.

Value for Money

As you would expect from a pre-workout supplement with such generous doses and wide-range of ingredients, PreSeries BULK isn't cheap.

With that said, it's also not the most expensive pre workout on the market. We think it provides excellent value for money - especially considering the great ingredients profile.

Pros & Cons

The Good:

  • Excellent ingredients profile for bulking
  • Transparent ingredient list
  • Great for focus & endurance
  • check-circle-o
    No artificial colorings
  • check-circle-o
    Clinically effective doses
  • check-circle-o
    Not overloaded with stimulants

The Bad:

  • Not a great taste
  • Relatively expensive


PreSeries BULK vs LEAN - What's the Difference?

As the name suggests, LEAN is designed for cutting while BULK is for bulking. What are the main differences between these two pre workout supplements though?

Both have similar ingredients, including Citrulline, Betaine, BCAAs, caffeine/L-theanine and Beta-Alanine. LEAN has a lower dose of Beta-Alanine though, so it may not provide the same benefit.

One of the biggest differences is that LEAN includes a "Thyroid Support" complex instead of BULK's "Testosterone Support" complex. This targets stubborn fat and prevents muscle loss rather than boosting muscle formation.

In short, both of these pre-workouts are great, but the right one depends on your goals.

Additionally, BULK's ingredients list and doses compare favorably with competitors such as Pre JYM, Pre-KAGED, NitroNOX, APS Nutrition Mesomorph and Nutrex Hemorage.

Are There Any Side Effects?

As we always say in our pre workout reviews, any supplement can potentially cause side effects. If you spend time on a bodybuilding forum, YouTube or Reddit, you'll almost certainly find examples of this. The clinically backed doses included with BULK mean that it's unlikely to cause problems though.

The most common side effect with pre-workouts containing beta-alanine is tingling in the skin. This is normal and harmless, although some people find it an annoyance.

Caffeine can also cause a jittery feeling or loss of coordination. The relatively low dose in BULK, combined with L-Theanine, helps to reduce this issue though.

As always, if you notice any side effects you should contact your doctor before continuing to use a preworkout supplement. You should also read the label carefully and avoid taking it if you're under 18, pregnant, nursing, have a medical condition or are on prescription medication.

Will It Help Running or Other Types of Cardio?

PreSeries BULK is primarily a weight lifting or bodybuilding supplement, but it can help with cardiovascular workouts too.

This is because BULK is great for increasing endurance and energy. It allows you to workout harder and with higher intensity, whether you're running, doing CrossFit, lifting weights or playing a team sport.

You'll probably only need half a scoop for pure cardio workouts though.

Nutrition Facts: Is it Suitable for "X" Diet?

  • Gluten Free. Yes, BULK is gluten-free and suitable for people with an intolerance.
  • Vegetarian. Yes, all PreSeries products are vegetarian.
  • Vegan. Yes, all PreSeries products are suitable for vegans. Transparent Labs only use fermented vegan BCAAs.

Does BULK Increase Sexual Performance?

PreSeries BULK does contain a testosterone support matrix, but this only helps natural testosterone production and is not designed to improve sexual performance or problems with erections. You should visit your doctor if you have these issues.

Where Can I Buy PreSeries BULK? Is it Ever On Sale?

If you're looking to buy Pre Series BULK, the official website is the only place that sells it. It's currently not on sale at other online stores, including Amazon, Vitamin Shoppe, Walmart and GNC. Transparent Labs don't offer sample packs.

The good news is that Transparent Labs ships worldwide, including to the UK, Australia, Canada, New Zealand and Germany. They recommend allowing up to 14 business days for the product to arrive after purchase though.

At the time of writing, there are no discount codes or coupons that we could find. We'll update this page if we find a discount code or coupon though - or if other retailers start to sell it.


PreSeries BULK by Transparent Labs is one of the best pre-workout supplements we've had the chance to review. If you're looking to increase your lean muscle gains while enhancing almost every area of your workout, you can't go wrong with BULK.

PreSeries BULK




Focus & Energy


Pump & Fullness


Strength & Endurance


Value For Money