Transparent Labs BULK BLACK Review: 30-Day Results

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I have spent a lot of time testing and reviewing the Transparent Labs supplement line, including their Grass-Fed Whey Protein and their pre-workouts, Lean, Bulk, and Stim-Free

However, one of their pre-workouts, Bulk Black, has been sitting on my shelf for almost a year because I was waiting for a training cycle where I could really utilize the high-stim formula. 

Well, that time has arrived, and I just spent the past 30 days using Bulk Black and can share my results with you.  

I can confidently say that Transparent Labs has accomplished something with Bulk Black that almost no other supplement company has been able to do: offer a high-stim, clinically dosed pre-workout with high-quality ingredients at an affordable price point. 

If you are looking for a product that provides long-lasting energy without the feelings of jitteriness while supporting athletic performance and muscle growth, then there is a lot about Bulk Black that you are bound to appreciate.

But, as with any pre-workout, it’s not for everyone, which I’ll discuss below. 

Key Takeaways

Honest Review Guarantee from FeastGood: Our testing team purchases each product 100% independently and uses the product for several weeks up to several months before writing a review. Learn more about our review process here.

  • Transparent Labs Bulk Black comes in at $1.83 per serving (or $1.65 with the subscribe and save feature). While slightly above the average cost of pre-workout which is around $1.61, most other pre-workouts with similar formulas cost up to $3.00 per serving, making Bulk Black a phenomenal value
  • Transparent Labs Bulk Black uses clinical dosing for all of the ingredients that have doses established and uses high-quality ingredients. This combination of quality and quantity helps guarantee that Bulk Black will be an effective pre-workout
  • Transparent Labs Bulk is a great option for individuals looking for a high-stimulant formula that will also provide pump, strength, endurance, and power without side effects like jitteriness or a crash.

Overall Rating: 4.5/5

Take Transparent Labs Bulk
Take Transparent Labs Bulk


  • Transparent Labs Bulk Black is the newest addition to the Transparent Labs pre-workout lineup and is the high-stim counterpart to the original Transparent Labs Bulk. 
  • Bulk Black is also Informed Choice certified, guaranteeing that it is free of any banned substances and making it safe for use by elite or drug-tested athletes. 


  • Bulk Black is available for $1.83 per serving, which is a fantastic value for a clinically dosed, high quality product.
  • Bulk Black uses the same doses in its formula that have been proven effective in high quality research trials
  • Transparent Labs doesn’t use artificial flavors, sweeteners, or preservatives in its products.
  • Transparent Labs Bulk Black contains 2 sources of caffeine which provides a fast energy boost, but also provides a prolonged energy without a crash.

Best For

  • Individuals who value high-quality ingredients
  • Someone looking for a clinically dosed pre-workout
  • Someone looking in increase strength and muscle mass
  • Someone looking for a high-stim product
  • Anyone who is approaching the “peak phase” of their competition season

Medical Disclaimer: The material presented in this article aims to offer informational insights. It should not be perceived as medical guidance. The views and writings are not designed for diagnosing, preventing, or treating health issues. Always consult with your physician prior to starting any new dietary or supplement routine.

What Is Transparent Labs Bulk Black? 

Transparent Labs Bulk Black

Transparent Labs Bulk Black is the newest addition to the Transparent Labs pre-workout lineup and is the high-stim counterpart to the original Transparent Labs Bulk. 

Bulk Black contains a total of 450mg of stimulants, split up as 350mg of caffeine and 100mg of theobromine (more on those below). 

The combination of two different caffeine sources means that Bulk Black provides long-lasting energy that hits the system quickly and dissipates slowly. This helps prevent a post-workout crash and fuels even the longest and most grueling workouts. 

The other clinically dosed ingredients in Bulk Black make it a well-rounded pre-workout that will support muscle pump, strength, power, and recovery. 

When a company uses clinical doses, this means that their products contain the same doses of ingredients that have been used in clinical research trials and proven effective. 

While more and more companies are starting to use ‘clinical doses’ of ingredients, this is NOT the status quo. 

Further to the ingredients that support athletic performance, some of the ingredients in bulk also show potential for increasing muscle mass, supporting testosterone levels, and improving body composition. 

Like all Transparent Labs products, Bulk Black does not use artificial flavors or colors. It is third-party tested, and the results are publicly available online

Bulk Black is also Informed Choice certified, guaranteeing that it is free of any banned substances and making it safe for use by elite or drug-tested athletes.

Claims vs Reality:  How I Felt After Taking Transparent Labs Bulk Pre Workout?

Transparent Labs Bulk Black user experience

I was a bit tentative about testing Bulk Black since it’s such a high-caffeine formula, and it has been several months since I have tested a pre-workout dosed as highly as Black’s. 

My training program has also been very inconsistent over the past few months, so I felt like I wouldn’t be doing Bulk Black justice by testing its full scoop serving for 20-30 minute light calisthenics workouts. 

If, like me, you are in a phase of life where you are doing shorter or more cardio-focused workouts, then you would probably benefit more from Transparent Labs Lean, which I’ve reviewed on our YouTube channel here.

However, I’ve been consistently following a strength training routine for the past 30 days, and it was time to test Bulk Black.  

If I am being honest, I actually didn’t feel any different testing Bulk Black than I did when I tested the original Bulk formula, despite Black having almost twice the caffeine content. 

This isn’t necessarily a bad thing, because Transparent Labs Bulk happens to be one of my favourite all time pre-workout supplements. 

I expected to see a significant decrease in my overall strength and stamina because of my inconsistent training this year, but I was pleasantly surprised by how strong and consistent I felt in my lifting sessions while taking Bulk Black. 

Not only was I able to lift heavier than expected, but I ended up adding extra sets and exercises at the end of my workout because I had so much left in the tank. 

I consider myself to be pretty caffeine adapted, meaning I consume high levels of caffeine daily (typically around 400mg). This could be why I didn’t feel a big difference in total energy levels between taking Bulk which has 200mg of caffeine and Bulk Black which has 350mg. 

This is something to keep in mind if you’re someone who isn’t as caffeine-adapted as I am.  

One thing I really appreciated about Bulk Black was the fact that I didn’t have a crash afterwards. With so much caffeine, it’s not uncommon for some pre-workouts to have a massive energy rebound that leaves you feeling mentally and physically exhausted (I noticed this effect really bad with Redcon1 Total War).

Because of its high caffeine content, I made sure to use Bulk Black for morning and afternoon workouts, and I felt like I still had the capacity (mentally and physically) to get through busy days as a full-time employee and parent to two young kids. 

Bulk Black mixed up fairly easily and didn’t have a chalky or gritty texture. 

I personally tried the Cherry Kiwi flavor, and I found it to taste quite sour. I find this a common thread among all Transparent Labs pre-workouts, that even the flavors that are intended to be sweet have a sour quality to them.  (Note: I’ve actually tested every Transparent Labs Pre Workout Flavore, which you can learn more about here).  

You can remedy this by diluting them with extra water, but I personally prefer to have less water in my stomach during workouts. 

Transparent Labs Bulk Black Ingredients

Transparent Labs Bulk Black Ingredients
IngredientDoseClinical Effective DoseMeets Clinical Standards
Citrulline Malate8000 mg6000 - 8000g
Beta-Alanine4000 mg3000 - 6000g
Betaine Anhydrous2500 mg2500g
Taurine1300 mg1000 - 3000g
L-Tyrosine1000 mgn/an/a
Alpha-GPC300 mg300 - 600 mg
Natural Caffeine (From Green Coffee Bean)275 mgn/an/a
Infinergy™ (Dicaffeine Malate)75 mgn/an/a
L-Theanine200 mg200-400 mg
Theobromine100 mgn/an/a
Senactiv ®50 mg50 mg
Bioperine ®5 mg5 - 10 mg
Boron3000 mcgn/an/a


Citrulline is a nitric oxide enhancer that helps the body dilate and constrict its blood flow. This can improve blood flow to the muscles and may have a positive effect on cardiovascular health. 

Taking citrulline before your workout can  delay fatigue during high-intensity exercise, meaning you can workout harder for longer periods of time. It may also be beneficial for increasing strength and enhancing recovery.

Based on current research, the optimal dose of citrulline appears to be around 8000mg taken approximately 1 hour before exercise

With 8000mg per serving, Bulk Black meets clinical dosing standards. 


If you’ve ever felt a skin tingling sensation from pre-workout, you’ve experienced the common side effect from a popular pre-workout ingredient called beta-alanine. 

Beta-alanine increases muscle carnosine levels. Carnosine acts as  a buffer for hydrogen ions that build up in the muscles and cause fatigue

By supplementing with beta-alanine, you will be able to lift heavier weights or travel farther distances doing cardio before muscle fatigue starts to set in. 

To maximize results, beta-alanine should be taken every single day (even on non-training days) and should have a loading phase of 3-6g daily for 4-10 weeks followed by a maintenance dose of 1.2g daily. 

With 4g of beta-alanine per serving, Bulk Black meets clinical dose standards for both the loading phase and maintenance. 

Betaine Anhydrous

Betaine is a compound found naturally in some foods like spinach and beets. It plays a key role in creating carnitine (not to be confused with carnosine mentioned above). 

Carnitine helps convert fat to energy and is a common ingredient in fat burners and some pre-workouts. 

Betaine is a compound that can be found naturally in foods like spinach and beets. It plays a role in creating carnitine, a substance that can help convert fat to energy. 

Theoretically, betaine shows potential for increasing strength and power output, but the research hasn’t been able to consistently back that claim. 

Research has shown, however, that betaine can help improve body composition by reducing fat mass and increasing lean mass. 

Clinical dosing for betaine is currently set at 2.5g daily. With exactly 2.5g per scoop, Bulk Black meets clinical dose standards. 


Taurine is an amino acid that is found naturally in animal products like meat, fish, and dairy. It plays a role in energy metabolism but it also has anti-inflammatory and antioxidant benefits. 

Taking taurine before exercise can increase performance in aerobic, strength, and power modalities and can enhance recovery. 

There is not a ton of research available to establish a definitive clinical dose, but so far the ideal strategy appears to be 1-3g taken 60-180 minutes before exercise

Bulk Black contains 1.3g per serving, meeting clinical dose standards. 


Tyrosine is an amino acid that acts as a precursor to dopamine and norepinephrine. 

In theory, supplementing with tyrosine should increase energy, mental focus, and delay fatigue

While there is some anecdotal support of lower doses of tyrosine (500mg-2000mg, what is typically found in a pre-workout supplement), the research that has actually studied tyrosine for improving athletic performance used much higher doses (7,000-10,000mg or the equivalent of 100-150mg per kg of body weight).

Bulk Black contains 1000mg of Tyrosine per serving. While this matches what many believe to be a sufficient dose to increase energy and delay fatigue, this falls below what is considered to be a clinically effective dose. 

Alpha GPC

Alpha GPC is a precursor to a chemical messenger called acetylcholine, which is essential for muscle control and bodily movements. 

Supplementing with alpha GPC can increase acetylcholine levels resulting in improved brain power and muscle function. 

To date, most of the research on alpha GPC has been done on older adults and invidiauls with Alzheimer’s. The limited research done on alpha GPC as a pre-workout supplement does show potential for increasing power and force output. 

A clinical dose of alpha GPC is currently accepted at 300-600mg taken 30-60 minutes pre-workout. 

Bulk Black contains 300mg of alpha GPC, meeting clinical dose standards. 

Organic Caffeine

Transparent Labs Bulk Black contains 275mg of natural caffeine from Green Coffee Bean. 

Bulk Black also contains a second type of caffeine called dicaffeine malate (at 75mg) which has a more gradual rise and fall than traditional caffeine. 

This combination provides the best of all worlds, giving you a quick energy boost (from the natural caffeine), but the longer lasting dicaffeine malate extends the energy you get from this pre-workout and helps prevent a subsequent crash. 

Taking caffeine before exercise is associated with improved performance in high-intensity training, improved muscular endurance, strength, power, and aerobic performance. 


Theanine is an amino acid that is found naturally in tea and has the ability to promote relaxation without causing drowsiness. 

Theanine does this by decreasing certain neurotransmitters in the brain associated with anxiety, while increasing the activity of other neurotransmitters like serotonin (your feel-good hormone) and dopamine. 

Theanine is commonly found in pre-workout supplements because when paired with caffeine, theanine can improve mental focus and reduce feelings of jitteriness or anxiety that are commonly associated with taking pre-workouts.

Optimal dosing of theanine appears to be 200-400mg daily and it may become more effective after several weeks of taking it consistently. 

Research also indicates that a 2:1 ratio of theanine to caffeine is ideal (e.g. having 200mg of theanine for every 100mg of caffeine).

Bulk has an almost inverted ratio, with 200mg of theanine to 350mg of caffeine. 

Bulk Black does still have the recommended 200mg dose , so by that standard Bulk Black does contain a clinically effective dose. 


Theobromine is a stimulant found in kola nuts, tea leaves, and chocolate that has similar effects to caffeine. 

As such, theobromine can increase cardiovascular and strength performance in the same way that traditional caffeine does. 

There isn’t an established clinical dose for theobromine, but the 100mg found in Bulk Black is twice the amount found in the original Bulk formula and will likely amplify and prolong the effects of the other stimulants and nootropics found in Bulk Black. 

Senactiv ®

Senactiv® is a patented product containing a blend of rosa roxburghii fruit and panax notoginseng root.  

Panax notoginseng enhances both aerobic capacity and endurance in adults. 

The dose of pure panax notoginseng used in clinical trials was 1350mg, but NuLiv Science, who manufactures Senactiv®, claims that the clinical dose for this specific patented product is 50mg. 

With 50mg per serving, Bulk Black meets clinical dose standards for Senactiv ®.

Bioperine ®

Bioperine® is a patented form of black pepper extract. Research has shown that Bioperine ® can increase nutrient absorption by up to 30%

As such, having Bioperine ® in your pre-workout can help your body absorb the ingredients found within the product, making your product more effective and helping to ensure you see the advertised benefits. 

Transparent Labs Bulk Black contains 5mg of Bioperine®, which is the established clinical dose


Boron is a mineral that may increase testosterone when taken as a supplement, as the supplement form allows you to take it at higher doses than you would typically eat naturally through food. 

I don’t feel confident making this claim definitively due to a lack of research, but so far it’s looking like a dose of a dose of 3mg (or 3000mcg) is effective. This is the same dose that is found in Bulk Black. 

Take Transparent Labs Bulk

Transparent Labs Bulk Black

Transparent Labs Bulk is a great option for individuals looking for a high-stimulant formula that will also provide pump, strength, endurance, and power without side effects like jitteriness or a crash.

Highlights: What I Like About Transparent Labs Bulk

Transparent Labs Bulk Black Pre Workout


Bulk Black is available for $1.83 per serving, which is a fantastic value for a clinically dosed, high quality product. 

Other pre-workouts with similar doses and quality cost between $2.00 and $3.00 per serving. 

Clinical Doses of High Quality Ingredients

Bulk Black uses the same doses in its formula that have been proven effective in high quality research trials. 

You will also notice a lot of patented ® and trademarked (™) ingredients in the formula. 

These ingredients have additional research behind them, further proving their safety and effectiveness. 

The end result is a pre-workout that is more likely to deliver on its advertised benefits like strength, power, endurance, and energy.  

No Artificial Additives

Transparent Labs doesn’t use artificial flavors, sweeteners, or preservatives in its products. 

Though artificial sweeteners like sucralose have been deemed mostly safe, some products like food dyes have been  linked to various health concerns

Combination of Caffeine Sources

Transparent Labs Bulk Black contains 2 sources of caffeine which provides a fast energy boost, but also provides a prolonged energy without a crash. 

I found that with the prolonged energy from Bulk Black, I didn’t feel the need to reach for other caffeine sources throughout my day.  

Bulk Black also features the addition of theanine which helps to reduce the feelings of jitteriness or anxiety that can come from taking highly caffeinated products. 

Drawbacks What I Did Not Like About Transparent Labs Bulk

High caffeine level might be harder to integrate

With 350mg of caffeine per scoop, this product might not be suitable for people who like to consume coffee and energy drinks or for people who workout in the evening. 

The FDA’s safe upper limit of caffeine in a day is 400mg, and Bulk Black does toe the line with 350mg of caffeine per serving. If you consume Bulk Black, I recommend not having any additional caffeine sources in your day.

The prolonged energy from the dual caffeine sources in Bulk Black also make it more likely that you will experience difficulty sleeping if you take this later in the day. 

If you are a late night lifter or are prone to insomnia, consider trying Transparent Labs Stim-Free instead. 

How Does Transparent Labs Bulk Stack Up Against Our Criteria For Pre-Workouts

Pre-Workout - TL Bulk Black


Our rating: 5/5 

You can purchase Bulk Black for as low as $1.65 per serving when you take advantage of the Subscribe & Save feature. Other comparable pre-workouts cost up to $3.00 per serving. 

Even at $1.83 per serving, Bulk Black provides phenomenal value. 

When you consider other factors like their Informed Choice certification, the third party testing, and the high quality ingredients, the value extends even further. 


Our rating: 3.5/5 

When mixed with the recommended amount of water (10-12oz), Bulk Black has a strong and sour taste. 

I didn’t necessarily find the sourness off putting, and I like that each of the different flavors does have a distinct taste. 

Some people may find Bulk Black too sour and/or wish to dilute it with more water. 


Our rating: 4.5/5

Bulk Black mixed easily with little to no leftover residue. 

There was a tiny amount of sediment left over, but I found that by swirling or gently shaking my cup as I drank my pre-workout, the powder didn’t get the opportunity to settle at the bottom of the cup. 


Our rating: 4.5/5

Bulk Black is designed for caffeine lovers and offers 350mg per scoop. Even though this is higher than the 200mg found in the orginal Bulk formula, I didn’t find the energy difference between the two to be substantial. 

This is, of course, my personal experience as someone who consumes high amounts of caffeine on a daily basis. 

Each person responds to caffeine differently, so even if you are an experienced pre-workout user I still recommend starting with a half scoop of Bulk Black to assess your personal tolerance before jumping into the full scoop serving. 


Our rating: 4.5/5

Bulk Black provides 8g of citrulline malate, which provides a good muscle pump. 

Muscle pump for me varies greatly based on my hydration and nutrition status. To optimize muscle pump, make sure to stay hydrated and carb up! 

I recently tested Transparent Labs Pump, which is a stim-free pre-workout that solely focuses on pump. The only reason why I’m not giving Black as 5/5 in the pump category is that Transparent Labs Pump is slightly better.   


Our rating: 5/5

The clinical doses of performance ingredients in Bulk Black allowed me to complete my prescribed workouts while feeling like I had extra gas in the tank. 

Even after taking a training hiatus, I felt strong throughout even the longest workouts and I felt like I had great recovery in between sets. 

This allowed me to do all of my prescribed sets and reps, and left me wanting to add extra sets or exercises to the end of my workout. 

Who Should Take Transparent Labs Bulk Black?

Who Should Take Transparent Labs Bulk? 

Transparent Labs Bulk Black is for:

  • Individuals who value high-quality ingredients: Transparent Labs is third party tested and use patented ingredients which have been proven safe and effective in clinical trials
  • Someone looking for a clinically dosed pre-workout: Bulk Black uses clinical doses for all ingredients which have clinical doses established. This helps ensure that your workout delivers on its promises.
  • Someone looking in increase strength and muscle mass: As its name suggests, Bulk has ingredients like taurine, betaine, and boron which help support increasing muscle mass and supporting testosterone levels.
  • Someone looking for a high-stim product: Bulk Black contains 350mg of caffeine, just below what the FDA recommends to be a safe upper limit (400mg). This product is for people who regularly consume caffeine and want one of the highest dosed products.
  • Anyone who is approaching the “peak phase” of their competition season: Bulk Black shouldn’t necessarily be a daily staple. Save this pre-workout for PRs and the most intense parts of your training season which require you to perform at your absolute best.

Who Should Not Take Transparent Labs Bulk? 

Transparent Labs Bulk Black is not for:

  • Anyone who is sensitive to caffeine
  • Individuals who workout in the evening
  • Individuals who don’t like sour tasting products

What Are Other Customers Saying About Transparent Labs Bulk?

Bulk Black has a 4.47/5 star rating on the Transparent Labs website, making it the highest rated pre-workout on their website. (The standard Bulk formula is in second place with 4.39/5 and Stim-Free not far behind with 4.35/5). 

That being said, Bulk Black is also the newest formula to be offered by Transparent Labs and has the smallest sample size. For example, the original Bulk formula has more than 1400 reviews on the Transparent Labs website and Bulk Black has only 649 reviews. 

People who shop directly from brand websites are more likely to already be fans of the brand and typically leave more positive feedback overall. 

The 4 and 5 star reviews praise Bulk Black for its high dosing and high quality ingredients. One user even remarked that he’s not typically a person for leaving reviews but felt compelled to express his love for Bulk Black to fuel him through his career in the military (though even he says the taste isn’t the best). 

Many reviewers have similar experiences to me in regards to the strength and stamina they experienced with Bulk Black, and users are relieved that they don’t experience negative side effects like jitteriness or stomach upset. 

I usually go to for larger sample sizes and a more accurate rating, but Amazon only has 58 reviews. 

Amazon was actually quite unforgiving with Bulk Black, and it has one of the lowest ratings of any product I have tested with a 3.9 out of 5 and only 45% of users giving it a 5 star rating. Amazon users are typically more honest in regards to negative feedback, though, and I wanted to see why people were dissatisfied with Bulk Black. 

Many people remarked that it worked really well, but it was the poor taste they didn’t like. Many people commented on the sour taste, over a variety of flavors which tells me that this is consistent and isn’t just isolated to my experience. 

Overall, the feedback is positive and consistent: This is a great and effective product, but the taste might not be for everyone. 

Transparent Labs Bulk Black Alternatives?

Transparent Labs Stim-Free

If you’ve made it this far through the article and love a lot of the benefits of Transparent Labs Bulk Black, but know that caffeinated products aren’t for you then I recommend trying Transparent Labs Stim-Free. 

The formulas are incredibly similar with one major trade off. 

Bulk Black has its sources of caffeine as well as ingredients to support prolonged energy and mental focus like alpha-GPC, theanine, and theobromine. 

In place of these ingredients, Transparent Labs Stim-Free has a patented ingredient called elevATP which has been clinically proven to increase intracellular ATP. This means it quite literally increases the amount of the energy molecule ATP in your body. 

This provides benefits that we typically see from stimulants, like increased strength and power output and reduced fatigue, but without any actual stimulants. 

Stim-Free has the same doses of performance ingredients as Bulk Black, like citrulline (8g), beta-alanine (4g), betaine (2.5g), taurine (1.3g) and tyrosine (1g). 

Stim-Free offers the same quality assurances as Bulk Black like third party testing and no artificial flavors or colors. 

Transparent Labs Bulk

As discussed above, the formulas found in Bulk and Bulk Black are virtually identical, with the only difference being the higher doses of overall stimulants found in Bulk Black. 

I personally think a good strategy is to use Transparent Labs Bulk as your day-to-day pre-workout, and saving Bulk Black for days or stretches when you really need the additional energy. 

Both formulas provide great pump, strength, and stamina but this way you shouldn’t build up a tolerance as easily to the high caffeine found in Bulk Black, which ensures that it stays more effective. 

(For what it’s worth, I think it’s also great to have some Stim-Free on hand for late night workouts when you still want to perform your best but don’t want to impact your sleep, or for when you are trying to cycle off of caffeine to reset your tolerance). 

The other benefit to Transparent Labs Bulk is that it costs slightly less than Bulk Black, with a regular cost of $1.66 per serving or $1.50 with the Subscribe & Save option.

Are There Any Promos or Discounts For Transparent Labs Bulk? 

Transparent Labs has a Subscribe and Save option which allows you to save $5 off of your pre workouts and free shipping. 

You can select your own delivery frequency (every 30, 45, or 60 days) and you can cancel at any time. 

You can also stay up to date on any current sales or promotions by subscribing to the Transparent Labs newsletter via their website or downloading the Transparent Labs app.

Frequently Asked Questions

Is Transparent Labs Bulk Black The Best Pre Workout?

Transparent Labs Bulk Black has clinical doses of very high quality ingredients, making it a highly effective pre-workout that also comes at a great value. The high level of caffeine (350mg) might be too high for some users.

Is Transparent Labs Bulk Third Party Tested? 

Transparent Labs Bulk Black is third party tested, with all of the testing results available publicly on their website.  

Is Transparent Labs Bulk Good For Weight Loss? 

Transparent Labs Bulk Black does contain some ingredients that can support fat metabolism like betaina dn stimulants. It is formulated more for supporting athletic performance and has ingredients that are beneficial for increasing strength and muscle building. For fat loss, Transparent Labs Lean will be a better fit. 

Is Transparent Labs Bulk Safe For Women? 

Transparent Labs Bulk Black is safe for women, and will be suitable for any women looking to increase strength and improve athletic performance. It should not be used while pregnant or breastfeeding. 

How Much Caffeine Does Transparent Labs Bulk Have? 

Transparent Labs Bulk contains 350mg of caffeine, plus 100mg of theobromine which is a compound similar to caffeine found in chocolate and tea. This caffeine comes from multiple sources to provide prolonged energy without a crash afterwards.

Does Transparent Labs Bulk Have Creatine?  

Transparent Labs Bulk does not contain creatine. 

How Long Does Transparent Labs Bulk Last For? 

You can start to feel the effects from Transparent Labs Bulk Black start approximately 20-30 minutes after consumption, and most of the benefits like pump and energy last for between 90 and 120 minutes. Bulk Black contains a patented form of caffeine that provides a long lasting energy that can be felt for several hours.

Does Transparent Labs Bulk Need To Be Cycled? 

Transparent Labs Bulk Black does not need to be cycled, but I recommend either not using it for every single workout, or taking a 1-2 week break every couple of months to reset your caffeine tolerance. 

Will Transparent Labs Bulk Make Me Jittery?

Transparent Labs Bulk Black contains ingredients to reduce feelings of jitteriness or anxiety associated with high caffeine products. Even still, Bulk Black contains 350mg of caffeine per serving and may cause jitteriness or insomnia. Start with a ¼ or ½ scoop serving to assess your personal tolerance. 

What Flavors Are Available For Transparent Labs Bulk? 

Transparent Labs Bulk Black is currently available in 7 different flavors: Cherry Kiwi, Blue Raspberry, Peach Mango, Sour Gummy, Black Cherry, Blueberry Pomegranate, and Watermelon Peach. Note that all flavors have a sour quality to them.

Where Is Transparent Labs Bulk Made? 

All Transparent labs products are manufactured in the USA out of a cGMP compliant facility in Utah. 

What Is Transparent Labs’ Shipping Policy? 

Shipping times and costs vary depending on where the product is being shipped to. Typically in the USA, items can arrive within 1-3 business days. International orders may take 14-21 business days.  

What Is Transparent Labs’ Return Policy? 

Unopened products can be returned within 30 days of purchase. If your product has been opened, you can request an exchange or store credit. Contact customer support ( to issue your return.

How To Contact Transparent Labs? 

You can reach out directly to Transparent Labs through their customer support phone line at 1-866-324-9557 or by e-mail at

You can also find Transparent Labs active on various social media outlets including Facebook, Instagram, TikTok, and Youtube


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About The Author

Jennifer Vibert

Jennifer Vibert is a Certified Strength and Conditioning Specialist, Nutrition Coach, and supplement store manager. She has a Bachelor of Kinesiology with a major in Fitness and Lifestyle and a minor in Psychology from the University of Regina. She is a Certified Nutrition Coach through Precision Nutrition, with a passion for helping clients learn the fundamentals of nutrition and supplementation in order to build healthy, sustainable habits.

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