From a performance standpoint, citrulline malate is the “star child” of pre-workout science.

We chose citrulline malate over L-arginine because it provides better absorption, higher plasma arginine levels, and has been found to:

• Improve strength, aerobic performance, and muscle endurance [1,2]
• Be at least twice as effective as L-arginine supplementation at raising nitric oxide [3]
• Participate in the Krebs Cycle(malate in citrulline malate [4]
• Enhance the use of branch chain amino acids like leucine during exercise [5]

PreSeries STIM-FREE contains 6,000 mg (6 grams) of citrulline malate per serving.

The "2:1:1" refers to the ratio of leucine, isoleucine, and valine (in that order). So, for every 2,000 mg of leucine, there are 1,000 mg of isoleucine and valine. 

Leucine

Leucine is the first branched-chain amino acid and is considered to be the most anabolic amino acid and is known for its strong activation of mTOR, the gene responsible for protein synthesis.

• Leucine has been found to significantly increase strength during workouts [26].
• Metabolites of leucine have been found to prevent muscle degradation and preserve lean mass [27].

PreSeries STIM-FREE contains 2,000 mg (2 grams) of leucine per serving.

Isoleucine

Isoleucine is one of the three branched-chain amino acids, which aids metabolism during workout, promotes muscle growth, and executes anti-catabolism effects [48, 49, 50].

PreSeries STIM-FREE contains 1,000 mg (1 grams) of isoleucine per serving.

Valine

Valine, the third branched-chain amino acid, is essential in pre-workout supplementation due to its involvement in metabolism and muscle growth. It also helps to reduce tryptophan build up in the brain during workouts. This allows for greater energy and endurance while working out.

PreSeries STIM-FREE contains 1,000 mg (1 grams) of valine per serving.

Supplementing with beta-alanine has been proven to increase cellular carnosine levels, which are quickly depleted during intense exercise [28, 29].

A majority of pre-workout supplements contain beta-alanine, but at significantly underdosed levels. Supplementing with proper dosing, as found in PreSeries STIM-FREE, is shown to:

• Delay the onset of neuromuscular fatigue in men and women during intense exercise [30]
• Provide a tingling sensation, which can be more aggressive (depending on tolerance), which is is normal and safe [33]
• Reduce and combat the formation of altered proteins and promote the formation of healthy proteins [31]
• Significantly increase lean mass and decrease fat in wrestlers [32]

Recent clinical studies suggest that betaine supplementation triggers a significant muscle growth response. This response is independent of testosterone and is significantly advantageous alongside typical supplementation protocols.

Betaine supplementation has also been shown to:

• Reduce fatigue when taken before and during weight training [34, 35].
• Increases total repetitions and volume on the bench press exercise versus placebo [37].
• In a recent study, betaine was found to significantly increase IGF-1, while decreasing cortisol in bodybuilding men [38].

PreSeries BULK contains 2,500 mg of betaine anhydrous per serving.

Taurine is an amino acid that is essential to pre-workout supplementation. Taurine competitively interacts with beta-alanine; thus, supplementation with beta-alanine and without taurine can lead to states of taurine deficiency [40].

Additionally, taurine used alongside BCAAs, has been found to reduce next-day muscle soreness more than when either are taken independently [39].

PreSeries STIM-FREE contains 1,300 mg (1.3 grams) of Taurine per serving.

N-acetyl L-tyrosine is the acetylated version of the amino acid L-tyrosine. The acetylation improves the absorption and effective period of L-tyrosine, as well as optimizes the effectiveness of the energy and focus ingredients in PreSeries STIM-FREE.

• L-tyrosine reduces the effects of stress and allows for greater mental focus and endurance [22].
• L-tyrosine improves memory and performance in bodily stressing climates, such as the cold [23].
• Believed to counteract the hypothyroid promoting conditions associated with extensive exercise.

PreSeries STIM-FREE contains 600 mg of N-acetyl L-tyrosine per serving.

Choline supplementation aids in regular intense training by maintaining acetylcholine levels for neural signaling, as well as participating in the BMHT pathway to covert homocysteine to methionine during prolonged sessions [41].

PreSeries STIM-FREE contains 500 mg of Choline Bitartrate per serving.

Mucuna Pruriens has been found to bring both psychological and physical benefits to athletes. Psychologically, Mucuna Pruriens counteracts stress and provides a clean “peace-of-mind” feeling. Physically, Mucuna Pruriens decreases cortisol, and promotes healthy testosterone levels in deficient men [24, 25].

PreSeries STIM-FREE contains 70 mg of Mucuna Pruriens (98% L-Dopa) per serving.

L-Norvaline directly reduces arginase activity in the body, which “up regulates” nitric oxide synthase’s (NOS) ability to produce Nitric Oxide from arginine [6].

Once in the body, citrulline malate is converted to arginine, which is then protected from in vivo arginase by L-norvaline, providing a stronger and longer NOS response.

PreSeries STIM-FREE contains 60 mg of L-norvaline per serving.

Bioperine is an extract obtained from the black pepper fruit. In its patented form, BioPerine has been clinically tested (in the United States) to significantly enhance the bioavailability of various supplement nutrients through increased absorption. 

PreSeries STIM-FREE contains 5 mg of BioPerine per serving.