Sources & References
WheyWijzer uses clinical dosage ranges to evaluate pre-workout supplements. Below you'll find the scientific sources our dosage standards are based on. All references are peer-reviewed studies, available via PubMed.
Stimulants
Caffeine
150mg - 400mg- Caffeine and Exercise: Metabolism, Endurance and PerformanceGoldstein ER et al. - J Int Soc Sports Nutr (2010)
- International society of sports nutrition position stand: caffeine and exercise performanceGuest NS et al. - J Int Soc Sports Nutr (2021)
Dynamine (Methylliberine)
100mg - 200mg- The effects of methylliberine and caffeine on cognitive functionCesareo KR et al. - J Int Soc Sports Nutr (2020)
Theacrine (TeaCrine)
100mg - 300mg- A two-part approach to examine the effects of theacrine (TeaCrine) on safety and hemodynamic responsesTaylor L et al. - J Caffeine Adenosine Res (2016)
p-Synephrine
10mg - 50mg- p-Synephrine alone and in combination with selected bioflavonoids: metabolic effects and safetyStohs SJ et al. - Int J Med Sci (2012)
Yohimbine
2.5mg - 10mg- Yohimbine: the effects on body composition and exercise performanceOstojic SM - Res Sports Med (2006)
Pump / Vasodilation
L-Citrulline (Malate)
3g - 10g- Citrulline malate enhances athletic anaerobic performance and relieves muscle sorenessPerez-Guisado J, Jakeman PM - J Strength Cond Res (2010)
- L-citrulline supplementation: Impact on cardiometabolic healthAllerton TD et al. - Nutrients (2018)
L-Arginine
3g - 9g- Acute L-Arginine supplementation increases muscle blood volume but not strength performanceAlvares TS et al. - Appl Physiol Nutr Metab (2012)
Nitrosigine (ASI)
750mg - 1.5g- Inositol-stabilized arginine silicate (ASI; Nitrosigine) for improved vasodilation and exercise performanceKalman D et al. - J Int Soc Sports Nutr (2015)
Agmatine Sulfate
500mg - 1.5g- Agmatine: multifunctional arginine metabolite and magic bullet in clinical neuroscience?Piletz JE et al. - Biochem Pharmacol (2013)
Glycerol
1g - 4g- Effects of glycerol-induced hyperhydration prior to exercise in the heatvan Rosendal SP et al. - Sports Med (2010)
Pine Bark Extract (Pycnogenol)
100mg - 300mg- Pycnogenol supplementation reduces exercise-induced oxidative stressBentley DJ et al. - Phytomedicine (2012)
Endurance / Performance
Beta-Alanine
2g - 5g- International Society of Sports Nutrition position stand: Beta-AlanineTrexler ET et al. - J Int Soc Sports Nutr (2015)
- Effects of beta-alanine supplementation on exercise performanceHobson RM et al. - Amino Acids (2012)
Creatine (Monohydrate)
3g - 5g- International Society of Sports Nutrition position stand: creatine supplementation and exerciseKreider RB et al. - J Int Soc Sports Nutr (2017)
- Creatine supplementation with specific view to exercise/sports performance: an updateCooper R et al. - J Int Soc Sports Nutr (2012)
Taurine
1g - 3g- The effect of acute taurine ingestion on endurance performanceWaldron M et al. - Amino Acids (2018)
Betaine (TMG)
1.5g - 2.5g- Betaine supplementation enhances anabolic endocrine and Akt signaling in response to acute bouts of exerciseApicella JM et al. - Eur J Appl Physiol (2013)
Electrolytes
200mg - 1g- Fluid and electrolyte needs for training, competition, and recoveryShirreffs SM, Sawka MN - J Sports Sci (2011)
Focus / Nootropics
L-Tyrosine
1g - 3g- Tyrosine improves cognitive performance and reduces blood pressure in cadets after one week of a combat training courseDeijen JB et al. - Brain Res Bull (1999)
- Effect of tyrosine supplementation on clinical and healthy populations under stress or cognitive demandsJongkees BJ et al. - J Psychiatr Res (2015)
L-Theanine
100mg - 400mg- L-Theanine and Caffeine in Combination Affect Human CognitionOwen GN et al. - Nutr Neurosci (2008)
Alpha-GPC
150mg - 600mg- The effect of alpha-glycerylphosphorylcholine on acute growth hormone responseZiegenfuss TN et al. - J Int Soc Sports Nutr (2008)
Choline
250mg - 500mg- Choline: an essential nutrient for public healthZeisel SH, da Costa KA - Nutr Rev (2009)
Lion's Mane
300mg - 1g- Improving effects of the mushroom Yamabushitake (Hericium erinaceus) on mild cognitive impairmentMori K et al. - Phytother Res (2009)
Huperzine A
0.05mg - 0.2mg- Huperzine A: a promising drug for Alzheimer's diseaseWang R, Tang XC - Acta Pharmacol Sin (2005)
GABA
500mg - 3g- GABA and l-theanine mixture decreases sleep latency and improves NREM sleepKim S et al. - Pharm Biol (2019)
Mucuna Pruriens
100mg - 500mg- Mucuna pruriens in Parkinson's disease: a double blind clinical and pharmacological studyKatzenschlager R et al. - J Neurol Neurosurg Psychiatry (2004)
Adaptogens
Rhodiola Rosea
200mg - 600mg- Rhodiola rosea: a phytomedicinal overviewPanossian A et al. - HerbalGram (2010)
Ashwagandha (KSM-66)
300mg - 600mg- Examining the effect of Withania somnifera on muscle strength and recovery: a randomized controlled trialWankhede S et al. - J Int Soc Sports Nutr (2015)
Vitamins
Niacin (Vitamin B3)
15mg - 50mg- Niacin in the Central Nervous System: An Update of Biological Functions and Clinical TrialsGasperi V et al. - Int J Mol Sci (2019)
Vitamin B6
1.5mg - 25mg- B vitamins and the brain: mechanisms, dose and efficacyKennedy DO - Nutrients (2016)
Vitamin B12
0.002mg - 0.5mg- Vitamin B12 among vegetarians: status, assessment and supplementationRizzo G et al. - Nutrients (2016)
Bioavailability
BioPerine (Piperine)
5mg - 10mg- Influence of piperine on the pharmacokinetics of curcumin in animals and human volunteersShoba G et al. - Planta Med (1998)
AstraGin
25mg - 50mg- Astragaloside IV and cycloastragenol enhance absorption of amino acids and glucoseLee S et al. - J Agric Food Chem (2017)
This page is regularly updated. All dosages are based on studies in healthy adults. Always consult a healthcare professional before using supplements.