Supplements

Leucine, Isoleucine, Valine (typically in a 2:1:1 or 4:1:1 ratio)

A supplement consisting of three essential amino acids — leucine, isoleucine, and valine. Multiple meta-analyses report a moderate reduction in delayed onset muscle soreness (DOMS), supporting post-exercise recovery. However, when total protein intake is already adequate, the incremental benefit of additional BCAA supplementation on muscle protein synthesis appears to be limited.

Dietary Nitrate, Beetroot Extract

Dietary nitrate found abundantly in beetroot is reported to be converted in the body via nitrite to nitric oxide (NO), promoting vasodilation and improved oxygen utilization efficiency. Multiple studies have shown modest benefits for aerobic and endurance performance, including improvements in VO2max and time-trial completion. Effects tend to be more pronounced in recreational to intermediate-level athletes than in elite competitors.

Betaine (Trimethylglycine, TMG)

Betaine is an amino acid derivative that acts as a methyl donor involved in creatine synthesis. Multiple RCTs have reported improvements in upper-body strength and muscle power, though results for lower-body outcomes are mixed. Cardiovascular benefits via homocysteine reduction are also under investigation.

Hydrolyzed Collagen Peptides (Type I/II/III)

A supplement providing hydrolyzed collagen peptides — the primary structural protein in tendons, ligaments, cartilage, and skin. RCTs suggest that co-ingestion with vitamin C may stimulate collagen synthesis in tendons and ligaments. Direct effects on muscle hypertrophy are limited, but research supports its role in joint health maintenance and injury prevention.

Nine essential amino acids: leucine, isoleucine, valine, lysine, methionine, phenylalanine, threonine, tryptophan, and histidine

A product containing all nine essential amino acids that the body cannot synthesize on its own. Research suggests that having the full complement of essential amino acids available is advantageous for muscle protein synthesis. BCAAs alone may leave other essential amino acids in short supply, and EAA is thought to provide a more complete substrate.

Beta-Hydroxy Beta-Methylbutyrate (HMB-Ca or HMB-FA)

HMB is a metabolite of leucine that research suggests may act on both the inhibition of muscle protein breakdown and the promotion of muscle protein synthesis. Evidence supporting its role in preserving lean mass is comparatively stronger in beginners, older adults, and those in a caloric deficit, while results in trained individuals seeking hypertrophy remain mixed across meta-analyses.

L-Theanine (green tea-derived amino acid)

An amino acid found in green tea, research suggests it increases alpha-wave activity to promote calm focus without sedation. Combined with caffeine, it may attenuate jitteriness and anxiety while preserving alertness. Evidence for standalone strength or performance benefits is limited; it is most studied as part of a caffeine stack.

Soy protein (isolate / concentrate)

A plant-based complete protein containing all nine essential amino acids, studied as a practical option for those with dairy allergies or following a vegan diet. Leucine content is somewhat lower than whey, which may result in a slightly smaller muscle protein synthesis response, but research suggests it is a useful tool for meeting total daily protein targets.

Taurine (2-aminoethanesulfonic acid)

Taurine is a sulfur-containing amino acid synthesized in the body that is known to play roles in antioxidant defense, cell membrane stabilization, and electrolyte balance regulation. Several RCTs have reported improvements in aerobic performance and reductions in post-exercise muscle damage markers and DOMS. While widely recognized as an energy drink ingredient, a growing body of research has examined its effects as a standalone supplement.

L-Alpha-Glycerylphosphorylcholine (Alpha-GPC)

Alpha-GPC is a precursor to acetylcholine, a key neurotransmitter involved in brain and neuromuscular activation. Research suggests that pre-exercise supplementation may promote growth hormone secretion and improve muscular strength and power output. Studies also indicate potential benefits for cognitive function and focus.

Withania somnifera root extract

An adaptogen herb used in Ayurvedic medicine. Multiple RCTs have confirmed associations with reduced cortisol, improved sleep, and enhanced muscle strength — making it one of the better-researched natural supplements.

L-Citrulline / Citrulline Malate

A non-essential amino acid that acts as a nitric oxide precursor, promoting vasodilation and improving blood flow and oxygen delivery to muscles. Has comparatively strong evidence as a pre-workout. Most research uses the citrulline malate complex.

Vitamin D3 (cholecalciferol)

A fat-soluble vitamin synthesized in the skin from sunlight. Involved in bone metabolism, immune function, and muscle function. Deficiency is common in indoor lifestyles and low-sunlight environments. Athletes show high deficiency rates, and associations with muscle strength, immunity, and bone density are well-researched.

Anhydrous caffeine

A pre-workout staple. Alongside alertness and focus, it gives a small boost to strength, power and endurance. Tolerance builds with habitual use, so timing matters.