A2
Creatine monohydrate
- Product declaration
- Creatine Monohydrate: 500 mg
- Selected studied range
- 3000 to 5000 mg
- Protocol and duration
- per day maintenance, after an optional loading phase
- Studied context
- The ISSN 2017 position stand calls creatine monohydrate "the most effective ergogenic nutritional supplement currently available to athletes" for increasing high-intensity/intermittent exercise capacity and lean body mass during training. It also describes research into post-exercise recovery, injury prevention, thermoregulation, rehabilitation, concussion/spinal-cord neuroprotection, and use in clinical populations (aging-related sarcopenia, neurodegenerative disease, type 2 diabetes glycemic control), while noting creatine is "of little value" for pure endurance sports (per NIH ODS).
- Limitations
- ISSN 2017 states it is not yet established whether other creatine forms (e.g., creatine nitrate, or precursors like guanidinoacetic acid/GAA) produce greater muscle or brain creatine uptake than monohydrate. This is described as an active area of research, not a settled finding.
Selected evidence: ISSN position stand on creatine safety and efficacy, 2017 · Open source
A1
L-arginine
- Product declaration
- L-Arginine: 500 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
