Transparent Labs Bulk Review: Results After 60 Days (2024)

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I have been testing and using various Transparent Labs products over the year, including the Grass Fed Whey Protein and LEAN Pre-Workout (both of which I’ve reviewed).  

I have grown to love the quality of their products, which is why I absolutely could not wait to get my hands on Transparent Labs Bulk. 

I have tested dozens of pre-workouts in my career managing a supplement store, and it’s almost impossible to find a product that contains clinical doses of key ingredients like citrulline, beta-alanine, and betaine, but is also lower in caffeine

Transparent Labs Bulk checks every box for criteria you should look for in a pre-workout. 

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.

Prefer to watch? Our video producer, Matteo Cantagallo, outlines the pros & cons.
  • Transparent Labs Bulk comes at a great value of $1.66 per serving. In an analysis of over 50 pre-workouts, the average cost is $1.61.  I’m not sure you’ll find a better pre-workout regarding “bang for your buck,” especially when considering the ingredients.
  • Transparent Labs Bulk uses clinical dosing for all of its ingredients, meaning it uses the same doses proven effective in research. These clinical doses make Bulk a highly effective pre-workout.
  • Transparent Labs Bulk is an excellent well-rounded option for individuals looking for pump, energy, and increased strength. It’s specifically formulated to support muscle building. 

Overall Rating: 4.5/5

Transparent Labs Bulk
Transparent Labs Bulk


  • Bulk is a comprehensive pre-workout that increases energy, strength, endurance, pump, and recovery.
  • Bulk’s 9 ingredients meet clinical dosing standards, meaning they match the effective quantities used in clinical trials


  • Great cost ($1.66 per serving)
  • Meets clinical dosing standards for all ingredients
  • No artificial flavors, sweeteners, or preservatives

Best For

  • Someone who values high-quality ingredients
  • Someone looking for a clinically dosed pre-workout
  • Someone looking to increase strength and muscle mass

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? 

Transparent Labs Bulk 1

Bulk is a comprehensive pre-workout that increases energy, strength, endurance, pump, and recovery. 

For all 9 ingredients, Bulk meets clinical dosing standards. What this means is that Transparent Labs contains the same quantities of ingredients that have been used in clinical research trials and proven effective. 

While you might think all supplement companies use ‘clinical doses’ for ingredients, this is NOT standard practice in the industry.  

Bulk contains ingredients that support increasing muscle mass and protein synthesis, strength, energy, endurance, and recovery. It also has ingredients to support testosterone levels and improve body composition. 

Bulk, as its name suggests, is a great all-around pre-workout formula for anyone whose goal is to increase muscle mass. 

Like all products by Transparent Labs, Bulk is third party tested with the results from certified labs, which are available publicly online.  Hence why the company is branded around “Transparency”.  

Related: Transparent Labs Bulk vs Lean: 6 Key Differences (TESTED)

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

Transparent Labs Bulk Pre Workout Claims vs Reality - user experience

One thing that is really key for me is that Bulk only contains 200mg of caffeine. 

I love to drink coffee or an energy drink throughout my day, and most of the time, clinically dosed pre-workouts bring me right up to the FDA’s upper limit of 400mg of caffeine. 

Even a pre-workout that I really enjoyed, like Legion Pulse, contains 350mg of caffeine per serving, which means that a single small cup of coffee would put me at 425mg, over the FDA’s guideline. 

I felt incredibly strong while using Bulk and found that my typical 45 minute workout didn’t feel long enough – I wanted to keep lifting. Bulk provided a really nice mix of mental focus and physical energy and I found that I had incredible stamina. 

With 4g of beta-alanine, this pre-workout is highly likely to cause paresthesia (skin tingling), but the tingling feeling subsided a bit more quickly than some other pre-workouts I have tried with similar doses. 

This could be due to where the beta-alanine is sourced from (different brands elicit slightly different results), but it could also be due to the fact that I have been taking pre-workout supplements daily for several months. 

Typically, the longer you use beta-alanine, the less you feel the skin tingliness associated with it.

My one downside to Bulk, which I’ve mentioned before in other pre-workout review articles, is that it is recommended to mix the product with 10-12 ounces of water. 

This is strictly a personal preference, but I find that that volume of water taken before my workout is too much – it sloshes around in my stomach and I have to go pee in the middle of my workout. 

Transparent Labs Bulk mixed with pina colada

When mixed with 12 ounces of water (pictured), the pina colada flavor that I tried did have a pleasant taste. When mixed with less water (around 8 ounces), the product had a pretty strong and bitter taste. 

Worth noting is that since Transparent Labs does not use any artificial sweeteners in its products, the flavor is a bit more bitter than other pre-workouts on the market. I didn’t mind it, but if you are very picky about flavor then it may be a less desirable option.  

Transparent Labs Bulk

Transparent Labs Bulk

Transparent Labs Bulk is a great option for individuals looking for a good pump, energy, and increased strength. It’s specifically formulated to support muscle building. 

Transparent Labs Bulk 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
Organic Caffeine200 mgn/an/a
L-Theanine200 mg200-400 mg
Theobromine50 mgn/an/a
Senactiv ®50 mg50 mg
Bioperine ®5 mg5 - 10 mg
Boron3000 mcgn/an/a
Transparent Labs Bulk Ingredients


Citrulline is a nitric oxide enhancer, helping the body to dilate and constrict its blood vessels. This improves blood flow to the muscles and can have a positive effect on heart health. 

Supplementing with Citrulline before your workout can delay fatigue during high-intensity exercise, increase strength, and enhance recovery. 

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

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


You might know beta-alanine as the ingredient that causes skin tingling, but what does it actually do? 

It increases muscle carnosine levels, which can act as a buffer for hydrogen ions that build up in the muscles and delay fatigue. This means you will be able to lift heavier weights or do more reps before fatigue starts to set in, allowing you to workout harder and longer. 

Beta-alanine is best taken every single day (even on non-training days), and should have a loading phase of 3000-6000mg daily for 4-10 weeks, followed by a maintenance dose of 1200mg daily.

Transparent Labs Bulk meets clinical dosing standards by offering 4000mg per serving.

Betaine Anhydrous

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 promise for improving strength and power output , but the research doesn’t fully back that claim. 

There is, however, research to support that betaine can improve body composition by reducing fat mass and increasing lean mass. 

For optimal results, betaine should be taken in a dose of 2500mg daily – which is exactly the amount offered by Transparent Labs Bulk.


Taurine is an amino acid that can be found naturally in meat, fish, dairy products, and human milk. It plays a role in energy metabolism and has anti-inflammatory and antioxidant properties. 

When taken pre-workout, taurine can increase aerobic endurance, increase strength, and power, and enhance recovery. 

There is limited research available, but the ideal dosing strategy appears to be 1000-3000 mg taken 60-180 minutes before exercise. Bulk contains 1300mg per serving, meeting clinical dosing standards


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

There is some controversy around tyrosine supplementation pre-workout, in that there are a lot of anecdotal claims that doses between 500mg and 2000mg provided increased energy and reduced time to exhaustion. 

The actual research, on the other hand, uses doses of 100-150mg per kg of body weight, which translates to between 7000-10,000 mg for a 150lb person, well above what’s found in pre-workout supplements. 

Transparent Labs Bulk contains 1000mg of Tyrosine, which may increase energy and total time to fatigue, but no clinical dose standards have been officially established.

Alpha GPC

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

Supplementing with alpha GPC will increase acetylcholine levels, thus improving brain power and muscle function. 

While most of the research surrounding Alpha GPC has been done regarding brain health in older adults and individuals with Alzheimer’s, Alpha GPC does show potential for increasing vertical jump power and bench press force. 

The clinical dose of Alpha GPC is accepted at 300-600mg taken 30-60 minutes pre-workout. With a dose of 300mg, Bulk meets clinical dose standards.

Organic Caffeine

Transparent Labs Bulk contains a patented form of organic caffeine, PurCaf®. 

This caffeine comes from green coffee, is ethically sourced, and USDA certified organic. 

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

Transparent Labs Bulk Pre workout


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

It does this by decreasing the activity of some neurotransmitters in the brain, which are associated with anxiety. It can also increase the activity of other neurotransmitters like dopamine and serotonin, your feel-good hormone. 

In regards to a pre-workout supplement, when theanine is paired with caffeine, it can improve mental focus and reduce jitteriness, a common side effect associated with pre-workouts. 

The ideal dosage appears to be 200-400mg daily, and it may become more effective after several weeks of consistent supplementation.

Research suggests that a 2:1 ratio of theanine to caffeine is ideal, but Bulk has a 1:1 ratio. Even still, it has the 200mg recommended dose, so for that purpose, Bulk meets clinical dose standards.


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

While it is similar to caffeine, it has a longer-lasting energy without the spike and crash associated with traditional caffeine. 

Like caffeine, theobromine can increase cardiovascular and strength performance

There isn’t a set clinical dose for theobromine, but the 50mg found in Bulk will help prevent a crash from the 200mg of PurCaf® caffeine.

Senactiv ®

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

Panax notoginseng has been shown to enhance 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 product is 50mg.

Transparent Labs Bulk meets clinical dosing standards with a dose of 50mg per serving.

Bioperine ®

Bioperine® is a patented form of black pepper extract. In clinical trials, Bioperine® was shown to increase nutrient absorption by up to 30%

When added to your pre-workout, Bioperine can help with the absorption of the ingredients. 

The clinical dose of Bioperine® is 5mg, which is the exact dose found in Transparent Labs Bulk.


Boron is a mineral that has claims of increasing testosterone when taken as a supplement in doses higher than we would typically eat naturally in food. 

There isn’t sufficient research for me to make the testosterone-boosting claim definitively, but preliminary research indicates that a dose of 3mg (or 3000mcg) is effective.

Highlights: What I Like About Transparent Labs Bulk

Pros vs Cons of taking Transparent Labs Bulk


At $1.66 per serving, Transparent Labs Bulk provides phenomenal value. 

When evaluating the cost of pre-workouts, the majority of high quality, clinically dosed products fall between $2.00 and $3.00 per serving. 


Transparent Labs Bulk meets clinical dosing standards for all ingredients that it uses for which those standards have been established. 

This results in a pre-workout that is highly effective and will increase endurance, strength, power, and energy while supporting muscle growth and recovery. 

No Artificial Ingredients

Transparent Labs uses no artificial flavors, sweeteners, or preservatives in its products. 

This reduces the likelihood of experiencing adverse side effects (since some products, like food dyes, have been linked to various health concerns). 

Caffeine Content

Transparent Labs Bulk contains 200mg of caffeine and 50mg of theobromine, which provide good sustained energy without a crash. The addition of L-Theanine helps prevent the jitteriness commonly associated with pre-workout supplements. 

The FDA’s safe upper limit of caffeine in a day is 400mg. Many pre-workout supplements that use clinical doses of ingredients like beta-alanine and citrulline also contain extremely high caffeine, between 350mg and 425mg per serving. 

Because Transparent Labs uses only 200mg of caffeine in their formula, you can safely add additional sources of caffeine into your day like a cup of coffee or an energy drink. 

This is a huge selling feature for me personally since I am unwilling to give up my morning coffee. When a product has around 400mg of caffeine, I tend to take only a half serving which in turn means I only get half doses of those other key performance ingredients. 

If you consider yourself to be a stim-junkie and you want the ultra-high caffeine content (300-400mg), you can add caffeine tablets, which are available in 100mg or 200mg doses

Drawbacks: What I Did Not Like About Transparent Labs Bulk

Requires Lots of Water to Mix

This isn’t just a drawback to Transparent Labs Bulk, but is a drawback to most clinically dosed pre-workouts. This may or may not be a drawback for you. 

When you have large doses, you have large scoops. As such, you need around 12oz (350ml or 1.5 cups) of water to mix it with for it to taste good and dissolve completely. 

For me personally, this volume of water pre-workout isn’t desirable, especially if I will be doing any kind of cardio or HIIT training. 

If you choose to concentrate this pre-workout (i.e. mix it with less water than recommended, like 8oz), the mixability is negatively affected and the taste becomes really sour. 

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

 Pre Workout Transparent Labs Bulk


Our rating: 5/5 

Other comparable pre-workouts cost anywhere from $2.00 to $3.00 per serving. 

When you also factor in that Transparent Labs doesn’t use any artificial flavors or sweeteners, and invests in publicly disclosed third party testing, the value is stretched even further.


Our rating: 4.5/5 

When mixed with the recommended amount of water (10-12oz), Bulk offers a fairly sweet and strong taste. 

Because they don’t use high amounts of artificial sweeteners and flavors to completely mask the taste of the raw ingredients, Bulk does have a slightly bitter aftertaste. 


Our rating: 4/5

If you mix Bulk with the recommended 10-12oz of water, it dissolves almost entirely. I did notice some small residue that settled at the bottom of my cup. 

If you shake/swirl your pre-workout as you drink it, the residue doesn’t get a chance to settle on the bottom. I didn’t find the particles off-putting, but it’s worth noting for people sensitive to texture that this product does not dissolve entirely. 


Our rating: 4/5

With 200mg of caffeine and a variety of energy and mental focus ingredients, Bulk provides really good energy and short-term mental focus without any crashes or jitteriness. 

This is relayed from my own personal experience. If you are very sensitive to caffeine, then it’s possible that you may still experience some jitteriness or anxiety since the 200mg is still equal to around 2 cups of coffee. In that case, I recommend trying Transparent Labs Stim-free Pre instead. (Click to read my review)

Transparent Labs Stim Free


Our rating: 4.5/5

With a full 8g of citrulline, Bulk provides a great muscle pump and vascularity, especially when doing traditional weight lifting workouts. 


Our rating: 5/5

Increasing strength is where Transparent Labs Bulk really shines. I felt like I was able to increase my weights for at least one set in every single exercise I did. 

When doing my morning workouts when I am under time restraints from having to get my kids up and off to daycare, I found myself wanting to get up even earlier just so that I had more time to work out. 

At the end of each of my morning strength workouts, I felt like I had extra sets left in the tank and I wanted to take advantage of them. 

Who should take Transparent Labs Bulk

Who Should Take Transparent Labs Bulk? 

Transparent Labs Bulk is for:

  • Someone who values high-quality ingredients
  • Someone looking for a clinically dosed pre-workout
  • Someone looking to increase strength and muscle mass

Who Should Not Take Transparent Labs Bulk? 

Transparent Labs Bulk is not for:

  • Someone looking to avoid stimulants
  • Someone whose priority is taste and mixability

What Are Other Customers Saying About Transparent Labs Bulk?

On the Transparent Labs website, Bulk has a 4.7 out of 5 star rating based on over 4000 reviews. 

A lot of the reviews provide very little feedback, typically only two to three words like “Great product” and “Super effective”. 

Many users had similar experiences to my own, citing that they loved that the product had good clean energy and focus with no crash and that they didn’t feel too tingly on it (despite it having 4g of beta-alanine). 

Bulk isn’t listed on Amazon, and I couldn’t sort the reviews by star rating on the Transparent Labs website so I was hard-pressed to find negative reviews to see what people didn’t like about this product. 

I made it to page 50 of the reviews, and still couldn’t find any negative reviews, but this could just be a limitation of how the reviews are sorted (e.g. if they are sorted from highest to lowest rating) and the website doesn’t let me jump to the last page of the reviews. 

I tried to do a deeper dive into Reddit and Quora to find more in-depth information about what people are saying about Bulk, but all I could really find was that Transparent Labs Bulk was listed on multiple different lists of “What are the best pre-workouts available” and was highly recommended on those sites as well. 

Transparent Labs Bulk Alternatives?

Transparent Labs Stim-Free

Transparent Labs Stim Free

For consumers who want the high, clinical doses offered by Transparent Labs Bulk, but want to avoid stimulants altogether then Transparent Labs Stim-Free is a great option. 

The formulas are very similar, but where Bulk has added ingredients to complement caffeine like Alpha-GPC, Theanine, and Theobromine, the Stim-Free formula is simplified and has an ingredient called elevATP added. 

ElevATP is a patented product that can increase intracellular ATP, literally providing the body with energy and exhibiting workout results similar to caffeine like increased strength and power output and reduced fatigue. 

The stim-free formula has the same full doses of Citrulline (8g), beta-alanine (4g), betaine (2.5g), taurine (1.3g) and tyrosine (1g). 

Legion Pulse

Legion Pulse Pre-workout

If you want quality ingredients with no artificial flavors or colors, but you want higher levels of caffeine then consider trying Legion Pulse

Legion Pulse contains clinical doses of citrulline (8g), beta-alanine (3.5g), betaine (2.5g), and alpha-GPC (300mg), but has 350mg of caffeine anhydrous, nearly double the caffeine dose found in Transparent Labs Bulk. 

Legion Pulse uses natural sweeteners and flavors, as well as stevia and vegetable juice to sweeten their products. 

Like Transparent Labs, Legion is third party tested. Legion Pulse does come at a higher cost per serving, however, at $2.25 per serving. 

Are There Any Promos or Discounts For Transparent Labs Bulk? 

Transparent Labs offers a Subscribe and Save feature if you order through their website, which allows you to save 10% off your product and get free shipping. 

With the Subscribe and Save feature, you can choose your delivery frequency (set to auto-ship every 30, 45, or 60 days) and you can cancel anytime. 

You can also stay up to date on all sales and promotions by subscribing to the Transparent Labs newsletter through their website. 

Frequently Asked Questions

Is Transparent Labs Bulk The Best Pre Workout?

Transparent Labs Bulk uses high quality ingredients, clinical doses, and has a caffeine level that will be acceptable for the majority of pre-workout users. This combination of factors, combined with a great cost per serving makes it one of the best pre-workouts on the market.

Is Transparent Labs Bulk Third Party Tested? 

Transparent Labs Bulk is third party tested. Transparent Labs displays all testing results publicly on their website. 

Is Transparent Labs Bulk Good For Weight Loss? 

Transparent Labs Bulk contains betaine and stimulants which can both be beneficial for reducing fat mass. While it contains ingredients to support muscle building, the increased energy output that Bulk provides combined with a calorie deficit could help facilitate fat loss. 

Is Transparent Labs Bulk Safe For Women? 

Transparent Labs Bulk is safe for women, and a great option for women looking to increase lean mass, reduce fat mass, and improve performance. It should not be used while pregnant or breastfeeding. 

How Much Caffeine Does Transparent Labs Bulk Have? 

Transparent Labs Bulk contains 200mg of caffeine, plus 50mg of theobromine which is a compound similar to caffeine found in chocolate and tea. 

Does Transparent Labs Bulk Have Creatine?  

Transparent Labs Bulk does not contain creatine. 

How Long Does Transparent Labs Bulk Last For? 

The effects of Transparent Labs Bulk start approximately 20-30 minutes after consumption, and last for between 90 and 120 minutes. The addition of theanine will help prevent an energy crash afterward. 

Does Transparent Labs Bulk Need To Be Cycled? 

Transparent Labs Bulk does not need to be cycled, but it is recommended to take occasional breaks to avoid building up a tolerance to caffeine. You can do this by taking 1-2 weeks off every couple of months or choosing not to use it for every workout. 

Will Transparent Labs Bulk Make Me Jittery?

Transparent Labs Bulk should not make you jittery, because they’ve added an ingredient called L-Theanine which helps promote relaxation when paired with caffeine. 

What Flavors Are Available For Transparent Labs Bulk? 

Transparent Labs Bulk is available in 12 different flavors: Strawberry Kiwi, Pina Colada, Blue Raspberry, Black Cherry, Peach Mango, Tropical Punch, Watermelon, Sour Grape, Green Apple, Orange, Strawberry Lemonade, and Lemon Lime.  

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 time and cost vary depending on where you are having the product shipped to. For shipping within the USA, items can arrive in as fast as 1-3 business days. Allow up to 14-21 business days for international orders. 

What Is Transparent Labs’ Return Policy? 

You can return products within 30 days of purchase if the product is unopened. Contact customer support ( to issue your return. If your product has been opened, you can request an exchange or online store credit.  

How To Contact Transparent Labs? 

Transparent Labs can be reached through their customer support phone line at 1-866-324-9557 or by e-mail at 

Transparent Labs is active on social media and can be found on Facebook, Instagram, TikTok, and Youtube

Transparent Labs Bulk

Transparent Labs Bulk

Transparent Labs Bulk is a great option for individuals looking for a good pump, energy, and increased strength. It’s specifically formulated to support muscle building. 


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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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I’ve Tested 28+ Pre-Workouts, Here’s My #1 Pick


  • Proven Doses: Ingredients Dosed To Clinical Standards
  • Great Value: 17% Cheaper Than Other Similar Formulas
  • Well-Rounded: Excellent for Pump, Energy, & Strength


  • Proven Doses: Ingredients Dosed To Clinical Standards
  • Great Value: 17% Cheaper Than Other Simliar Formulas
  • Well-Rounded: Excellent for Pump, Energy, & Strength

Read my review