A2
Beta-alanine
- Product declaration
- CarnoSyn Beta-Alanine: 800 mg
- Selected studied range
- 4000 to 6000 mg
- Protocol and duration
- per day in divided doses, for at least 2 to 4 weeks, not as a single pre-workout dose
- Studied context
- Studied for high-intensity exercise capacity in the 60-240 second range via elevation of muscle carnosine, which acts as an intracellular pH buffer against acidosis. ISSN 2015 position stand: greatest performance benefits in "open end-point" tasks/time trials lasting 1-4 minutes; some benefit noted in aerobic exercise up to roughly 25 minutes; attenuation of neuromuscular fatigue, particularly noted in older adults.
- Limitations
- Strength/resistance-training outcomes remain mixed; training volume may increase without a clear strength gain. Tasks under 60 seconds do not show benefit. Endurance benefit beyond about 25 minutes is not established. Long-term safety data beyond roughly a year, and effects in special/tactical populations, are flagged as needing more research.
Selected evidence: ISSN position stand on beta-alanine, 2015 · Open source
A2
Taurine
- Product declaration
- Taurine: 500 mg
- Selected studied range
- 1000 to 3000 mg
- Protocol and duration
- per day, acutely across 6 to 15 days
- Studied context
- Studied for aerobic performance (VO2max, time-to-exhaustion, time-trial performance), anaerobic/strength performance, exercise-induced muscle damage, and recovery. A 2018 review ("Taurine in sports and exercise," PMC8152067) reports small-to-moderate improvements across several of these outcomes in some studies.
- Limitations
- The 2018 review states plainly: "limited and varied findings prohibit definitive conclusions regarding the efficacy of taurine on aerobic and anaerobic performance," and separately notes no peer-reviewed evidence exists for an independent role of taurine in skeletal-muscle hypertrophy.
Selected evidence: Taurine in sports and exercise, 2018 · Open source
A1
L-arginine
- Product declaration
- L-Arginine: 200 mg
- Selected studied range
- 2000 to 20000 mg
- Protocol and duration
- per day across the studies NIH ODS reviewed
- Studied context
- Plain L-arginine has been studied for exercise-related vasodilation, blood flow, and exercise metabolites, per NIH ODS. The branded ingredient Nitrosigine (inositol-stabilized arginine silicate) has been studied in a series of company-funded and academic trials for acute and sustained plasma arginine elevation, exercise-induced muscle damage markers (serum creatine kinase), perceived energy, and post-exercise cognitive performance. A randomized double-blind study (PMC5133120) reported cognitive-test-score changes (including RBANS measures) in healthy physically active adults.
- Limitations
- NIH ODS states plain arginine supplementation shows "little to no effect on vasodilation, blood flow, or exercise metabolites" and "little to no enhancement of athletic performance" overall. A notably weak evidence verdict for the free amino acid form. For Nitrosigine specifically, this research pass relied on the trademark holder's own technical page and holder-affiliated trial write-ups (A3-level sourcing); no independent NIH/FDA/EFSA evaluation of Nitrosigine's efficacy claims was located.
Selected evidence: NIH ODS, Dietary Supplements for Exercise and Athletic Performance · Open source
A2
Caffeine
- Product declaration
- Total caffeine from all declared sources: 100 mg
- Selected studied range
- 140 to 420 mg
- Protocol and duration
- 2 to 6 mg per kg body mass, 15 to 60 minutes before exercise, shown here for a 70 kg adult
- Studied context
- Studied for endurance-type aerobic exercise (moderate to large ergogenic effect, most consistent evidence category per ISSN 2021), muscular endurance and movement velocity in resistance exercise (small to moderate effects), sprinting/jumping/throwing (2-7% improvements), and cognitive attention/vigilance under fatigue. NIH ODS notes it "might enhance performance in endurance-type activities... And intermittent, long-duration activities."
- Limitations
- Minimal effective dose remains unclear. Repeated-sprint performance benefit is inconsistent and the ISSN position stand says this "requires further research." Effects of habitual/chronic caffeine use on the ergogenic response are described as equivocal.
Selected evidence: ISSN position stand on caffeine and exercise performance, 2021, with NIH ODS · Open source