A2
Citrulline malate
- Product declaration
- L-Citrulline Malate 2:1: 6 g
- Selected studied range
- 6000 to 8000 mg
- Protocol and duration
- single acute dose, 40 to 60 minutes before training
- Studied context
- Studied for resistance-exercise repetition performance/muscular endurance, cycling performance, muscle-damage recovery, and muscle soreness. A 2021 critical review notes a single acute 8 g dose "may, albeit not consistently, increase muscular endurance-strength performance," with a meta-analysis finding an average 6.4% increase in repetitions with 6-8 g dosed 40-60 minutes pre-exercise, with a stronger trend for lower-body than upper-body exercises.
- Limitations
- The same review states there is "little evidence to advocate its use in the production and maintenance of muscular power, maximal strength, recovery of muscular function, or supporting muscular adaptations," calls cycling-performance effects "scarce," and says claims about reduced muscle soreness lack consistent support. Overall efficacy is called "ambiguous." The review also flags a real-world quality-control problem: commercial products often do not match the citrulline:malate ratio used in the research they cite.
Selected evidence: A critical review of citrulline malate supplementation and exercise performance, 2021 · Open source
A2
Creatine monohydrate
- Product declaration
- Creatine Monohydrate: 5 g
- 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
A2
Beta-alanine
- Product declaration
- Beta Alanine: 3.2 g
- 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
Caffeine
- Product declaration
- Total caffeine from all declared sources: 350 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