L-Citrulline Malate (2:1) | 8,000 mg

L-citrulline is an amino acid naturally found in watermelon that plays an important role in kidney function. It's become a popular ingredient in pre-workout supplements due to its ability to boost nitric oxide levels [1]. When nitric oxide production increases, blood flow improves, allowing nutrients and oxygen to replenish muscle tissue more efficiently. 

Ultimately, this translates to greater muscle pumps and heightened energy levels.
 

Numerous studies have demonstrated the ergogenic effects of L-citrulline malate, the citrulline salt of malic acid, such as:

• Improving strength, aerobic performance, and muscle endurance [2, 3]
• Elevating nitric oxide levels even more than equivalent doses of L-arginine [4]
• Enhancing muscle anabolism and reducing muscle catabolism [5]

Beta-Alanine | 4,000 mg 

Beta-alanine is a beta-amino acid that combines with L-histidine to form a dipeptide known as carnosine. Supplementing with beta-alanine has been shown to increase muscle carnosine levels, which are quickly depleted during intense exercise [6].
 

Carnosine is an endogenous dipeptide that functions as a buffer in muscle cells, thereby attenuating the accumulation of acidic byproducts of muscular exertion (e.g. lactate and hydrogen ions) [7]. Hence, bolstering muscle carnosine levels—via beta-alanine—allows you to push yourself longer and harder in the gym.
 

Pre-workout supplements almost always contain beta-alanine but in inefficacious doses. We made sure to include a full clinical dose of beta-alanine (4,000 mg) in every scoop of BULK Pre-Workout. Relevant evidence-based benefits of beta-alanine include:

• Delaying the onset of neuromuscular fatigue during intense exercise [8]
• Increasing overall muscle strength [9] 
• Improving muscle endurance and total work capacity [10]
• Reducing and combatting the formation of dysfunctional proteins and promoting the formation of healthy proteins [11]
• Significantly increasing lean muscle mass as part of a diligent resistance-training program [12]
   

*Note that beta-alanine causes a benign tingling sensation known as paresthesia while the body acclimates to higher carnosine levels. This effect is harmless and gradually lessens with consistent use.

BetaPure™ Betaine Anhydrous | 2,500 mg

Taurine | 1,300 mg

Taurine is another staple pre-workout ingredient with diverse benefits for athletes and gym-goers. For one, taurine is a potent nootropic that confers synergy with caffeine to promote focus and reduce brain cell inflammation and oxidative stress [17, 18]. 
 

Taurine can also enhance physical performance via increased blood flow to skeletal muscle tissue [19, 20]. Greater blood flow to muscle tissue encourages a favorable milieu for muscle function and recovery during training. Additionally, taurine supplementation has been shown to improve performance in endurance athletes [21].

L-Tyrosine | 1,000 mg

AlphaSize® Alpha-GPC | 300 mg

Alpha-GPC (glycerylphosphorylcholine) is a popular nootropic supplement and a bioavailable source of choline, an essential micronutrient for cholinergic transmission and, by extension, cognitive function. Alpha-GPC is primarily found in the brain and is one of the two major storage forms of choline in the cytosol (interior space of cells), along with phosphocholine [24].
 

This ingredient can enhance physical and mental performance by increasing acetylcholine and growth hormone production [25, 26, 27]. The former is important for focus and mental acuity, while the latter promotes fatty acid oxidation and reduces muscle tissue breakdown. As such, alpha-GPC (as patented AlphaSize®) is one of the key ingredients in Bulk Pre-Workout.

PurCaf® Organic Caffeine | 275 mg

While most pre-workouts contain synthetic caffeine anhydrous, we formulated BULK Black Pre-Workout with organic caffeine derived from green coffee beans (as PurCaf®). 

On the molecular level, caffeine (chemically known as 1,3,7-trimethylxanthine) is an alkaline, organic substance derived from xanthine — a biologically important purine base found in many bodily tissues and fluids. Methylxanthines like caffeine and theobromine stimulate the central nervous system (CNS) and heart to promote wakefulness and motivation.
 

Numerous studies have shown that taking caffeine before exercise can significantly improve overall performance, largely by reducing the rate of perceived exertion [28]. Caffeine may also enhance endurance and strength by increasing fatty acid oxidation and sparing muscle glycogen [29].

L-Theanine | 200 mg

L-theanine is an isomer of the amino acids L-glutamate and L-glutamine. It was discovered centuries ago as one of the primary amino acids in green tea leaves and is also found in various mushroom species.
 

L-theanine is highly bioavailable when taken orally and actively traverses the blood-brain barrier to enhance mental acuity and attenuate stress [30, 31]. Its nootropic effects are appropriately described as "alert relaxation," which is to say it promotes a sense of calmness while improving focus. L-theanine can also help take the edge off of stimulants, particularly caffeine. 

In fact, research shows that pairing L-theanine with caffeine creates a nootropic synergy that bolsters cognitive function and alertness more effectively than taking either nootropic on its own [32].

Theobromine | 100 mg

Theobromine is the primary alkaloid found in cocoa beans and is essentially the “little brother” of caffeine. Its functions in the body are suggested to be complementary to those of caffeine, acting as a phosphodiesterase inhibitor and central nervous system stimulant [33].

Research has also found that theobromine has differential contributions to mood and cognitive function compared to caffeine, providing further insight into the distinct yet synergistic nature of these naturally occurring stimulants [34].

Infinergy™ Di-Caffeine Malate | 75 mg

SenActiv® | 50 mg

BioPerine® | 5 mg

Boron Citrate | 3,000 mcg (3 mg)

Zinc Chelate | 10 mg

Vitamins B6 and B12 | 5 mg and 100 mcg

Sodium and Potassium | 180 mg and 125 mg