Ingredients
What we cover, the effective dose ranges from human studies, and how strong the evidence is.
26 ingredients found
Preworkout
Agmatine Sulfate
1/5
Agmatine is a compound made from the amino acid arginine that acts on several receptor systems and is thought to influence nitric oxide regulation. It appears in preworkouts marketed for "pumps" and focus, but human research has centered on neuropathic pain and safety, not exercise.
Preworkout
Alpha-GPC
300–600 mg effective dose
2/5
Alpha-GPC (alpha-glycerophosphocholine) is a choline-containing compound that supplies a precursor for acetylcholine, a neurotransmitter essential for muscle contraction and cognitive function. This mechanism underlies its use as a pre-workout ingredient aimed at power and focus.
Preworkout
BCAAs (Branched-Chain Amino Acids)
5–10 g effective dose
2/5
Branched-chain amino acids are three essential amino acids - leucine, isoleucine, and valine - commonly sold as a recovery and intra-workout supplement. Leucine in particular signals the mTOR pathway that initiates muscle protein synthesis, which is the mechanism behind most BCAA marketing claims.
Preworkout
Beetroot (Dietary Nitrate)
370–740 mg effective dose
4/5
Beetroot is a concentrated dietary source of inorganic nitrate, which the body converts through nitrite into nitric oxide. This pathway improves blood flow and reduces the oxygen cost of exercise, supporting endurance and muscular efficiency.
Preworkout
Beta-Alanine
3.2–6.4 g effective dose
4/5
Beta-alanine is a non-essential amino acid that combines with histidine to form carnosine in muscle tissue. Carnosine buffers acidity during high-intensity work.
Preworkout
Betaine Anhydrous (TMG)
2.5–6 g effective dose
3/5
Betaine anhydrous, also called trimethylglycine (TMG), is a compound found in beets and other foods that acts as an osmolyte and methyl donor. By supporting cellular hydration and methylation reactions, it is theorized to aid power output and body composition during training.
Preworkout
Caffeine
100–400 mg effective dose
5/5
Caffeine is a central nervous system stimulant and the most studied ergogenic aid in sport science. It blocks adenosine receptors, reducing perceived exertion and improving alertness.
Preworkout
Citicoline (CDP-Choline)
250–500 mg effective dose
3/5
Citicoline, also called CDP-choline, is a naturally occurring compound that supplies choline and cytidine, precursors used to build the neurotransmitter acetylcholine and brain cell membranes. By supporting cholinergic signaling, it is studied as a nootropic for attention and focus.
Preworkout
Citrulline Malate
6–8 g effective dose
3/5
Citrulline malate pairs L-citrulline with malic acid, an intermediate in energy metabolism. The citrulline portion supports nitric oxide production and blood flow, while malate is theorized to aid energy turnover, though the combined mechanism is not fully established.
Preworkout
Cordyceps
1–3 g effective dose
2/5
Cordyceps is a genus of fungi (commonly Cordyceps militaris and Cordyceps sinensis) used in supplements aimed at aerobic endurance and oxygen utilization. It is proposed to influence cellular energy production and oxygen kinetics, but the human performance evidence is preliminary and inconsistent.
Preworkout
EAAs (Essential Amino Acids)
1.5–18 g effective dose
4/5
Essential amino acids (EAAs) are the nine amino acids the body cannot make and must obtain from food. Supplemented in free form, they directly stimulate muscle protein synthesis, with leucine acting as the primary trigger of the anabolic signaling response.
Preworkout
Electrolytes
4/5
Electrolytes are the charged minerals lost in sweat—chiefly sodium, potassium, magnesium, and chloride—that the body uses to regulate fluid balance, nerve signaling, and muscle contraction. During prolonged or heavy sweating, replacing them (especially sodium) helps the body retain ingested fluid and maintain plasma volume rather than passing the water through. They do not provide energy or stimulation; they support hydration.
Preworkout
Glycerol
1–1.2 g/kg effective dose
3/5
Glycerol is a sugar alcohol that draws and holds water in the body through its osmotic properties. Taken with a large fluid load before exercise, it expands total body water (hyperhydration), which can help athletes resist dehydration in heat or long events.
Preworkout
HMB
3–3 g effective dose
3/5
HMB (beta-hydroxy-beta-methylbutyrate) is a metabolite of the amino acid leucine. It is thought to reduce muscle protein breakdown and support repair, which is why it is studied mainly for recovery and preservation of lean mass.
Preworkout
Huperzine A
200–400 mcg effective dose
2/5
Huperzine A is an alkaloid extracted from the Chinese club moss Huperzia serrata. It is a reversible acetylcholinesterase inhibitor, meaning it slows the breakdown of the neurotransmitter acetylcholine, which is why it is included in nootropic and pre-workout focus blends.
Preworkout
L-Arginine
1.5–12 g effective dose
3/5
L-arginine is an amino acid that serves as the substrate for nitric oxide synthesis, which helps regulate blood vessel dilation and blood flow to working muscle. Supplement marketing positions it as a "pump" and endurance aid, though much of the orally ingested dose is metabolized in the gut and liver before reaching circulation.
Preworkout
L-Citrulline
6–8 g effective dose
3/5
An amino acid that the body converts to L-arginine, raising plasma arginine more reliably than supplemental arginine itself. This supports nitric oxide synthesis and vasodilation.
Preworkout
L-Glutamine
6–30 g effective dose
2/5
L-glutamine is the most abundant amino acid in the body and a fuel source for immune and gut cells. Plasma glutamine falls after prolonged exercise, which led to the theory that supplementing it could aid recovery and immunity.
Preworkout
L-Ornithine
2–6 g effective dose
2/5
L-ornithine is a non-protein amino acid that participates in the urea cycle, the pathway the body uses to clear ammonia produced during protein metabolism and intense exercise. Because rising ammonia is linked to fatigue, ornithine is studied as an anti-fatigue and recovery aid.
Preworkout
L-Theanine
100–200 mg effective dose
3/5
L-theanine is an amino acid found mainly in tea leaves that influences brain activity, increasing alpha waves associated with relaxed alertness. It is most often used alongside caffeine, where it appears to smooth caffeine's stimulant edge.
Preworkout
L-Tyrosine
100–150 mg effective dose
2/5
L-tyrosine is an amino acid that serves as a precursor to the catecholamine neurotransmitters dopamine and norepinephrine. Under acute stress these neurotransmitters can become depleted, and supplemental tyrosine may help replenish them to support cognitive function.
Preworkout
Nitrosigine (Inositol-Stabilized Arginine Silicate)
1500–1500 mg effective dose
2/5
Nitrosigine is a patented complex of arginine, silicate, and inositol designed to deliver arginine more effectively than arginine alone. Arginine is a precursor to nitric oxide, a vasodilator that widens blood vessels and increases blood flow, which is the basis for its use in pre-workout formulas.
Preworkout
Sodium Bicarbonate
0.2–0.3 g effective dose
4/5
Sodium bicarbonate (baking soda) is an alkalizing agent used as an ergogenic aid before high-intensity exercise. It works as an extracellular buffer, raising blood bicarbonate so hydrogen ions produced during intense effort can be cleared faster, delaying the drop in muscle pH that contributes to fatigue.
Preworkout
Taurine
1–3 g effective dose
3/5
Taurine is a conditionally essential amino acid concentrated in muscle, heart, and brain tissue. It is involved in calcium handling, cell hydration, and antioxidant defense, mechanisms that may modestly support muscle function during exercise.
Preworkout
Theacrine
200–300 mg effective dose
3/5
Theacrine is a purine alkaloid structurally related to caffeine, found naturally in the kucha tea plant and sold commercially as TeaCrine. It is thought to act on adenosine and dopamine signaling to support energy and focus, but unlike caffeine it appears not to raise heart rate or blood pressure at typical doses.
Preworkout
Yohimbine
0.2–0.2 mg/kg effective dose
2/5
Yohimbine is an alkaloid from the bark of the African yohimbe tree and a potent stimulant. It blocks alpha-2 adrenergic receptors, increasing the release of noradrenaline, which can mobilize fat and raise alertness but also drives its cardiovascular and anxiety effects.