Creatine in mg/kg: scientific calculation Maintenance: 0.07 g/kg/day. Loading: 0.3 g/kg/day for 5–7 days.
This guide explains the rationale, gives a precise protocol, and covers the edge cases (timing with food, training, fasting) so you can dose creatine with confidence.
Creatine is a naturally occurring compound synthesized in the liver, kidneys, and pancreas from arginine, glycine, and methionine. About 95% of body creatine resides in skeletal muscle, with the remainder in brain, heart, and other high-energy tissues. Dietary creatine comes primarily from red meat and fish (~1 g/day in omnivores; near-zero in vegans).
Inside cells, creatine is phosphorylated to phosphocreatine (PCr), which serves as a rapid ATP-regeneration system. During short, high-intensity efforts (1–10 seconds), the ATP–PCr system is the dominant energy supplier. Creatine supplementation increases muscle PCr stores by 10–40%, improving repeat-effort performance, strength, and lean mass gains over weeks of consistent training.
Beyond muscle, creatine has well-documented brain effects. The brain uses creatine for cognitive demands and during stress (sleep deprivation, hypoxia, mental fatigue). Vegetarians, vegans, women, and older adults have consistently shown the largest cognitive benefits — likely because their baseline brain creatine is lower. Therapeutic uses are emerging in depression, ADHD, traumatic brain injury, and Parkinson's disease as adjunctive support.
Creatine monohydrate is the gold standard form — over 1,000 published studies, ~99% absorption, and the lowest cost-per-effective-dose of any major supplement. The patented Creapure form (manufactured in Germany by AlzChem) is the most-tested creatine raw material globally and is used by premium brands. Other forms (HCl, buffered Kre-Alkalyn, ethyl ester, magnesium chelate, liquid, gummies) marketed as "more bioavailable" or "less bloating" do not have evidence supporting superiority over monohydrate; they typically cost 2–5× more for equivalent or inferior effect.
Standard adult dose is 5 g/day taken consistently — timing is largely irrelevant, though post-workout with carbohydrate and protein modestly improves muscle uptake. A loading phase (20 g/day for 5–7 days) saturates muscle creatine faster but is not required. Hair loss concerns from a single 2009 rugby player study showing DHT increases have not been replicated; the evidence does not support clinically meaningful hair-loss risk. Kidney concerns in healthy adults are not supported by evidence; existing kidney disease warrants medical discussion. Creatine retains roughly 1–2 kg of water in muscle (intracellular), which is desirable, not a side effect.
Why this dose works. Allows precise scaling. 70 kg adult: 5 g maintenance, 21 g loading.
Clinical context. Most creatine trials use 3–5 g/day maintenance with optional 20 g/day loading. ISSN and ACSM position statements endorse this dosing range. Daily consistency over weeks matters far more than acute timing or exotic delivery formats.
Exact protocol. Maintenance: 0.07 g/kg = standard 5 g for 70 kg. Loading: 0.3 g/kg = 21 g/day for 70 kg.
Stack notes. Pair with adequate protein (1.6–2.2 g/kg for body composition), magnesium glycinate (ATP cofactor), electrolytes for training, omega-3 for general health.
Tracking. Strength on key lifts at 4 and 8 weeks; lean mass via DEXA at 12 weeks; subjective performance and recovery.
What if I miss a dose of creatine?
Skip and resume normal schedule. Daily consistency matters but missing one day has minimal impact on saturation.
How long until creatine works?
Loading: 7 days for muscle saturation. No loading: ~28 days. Subjective performance changes by week 4.
Can I take creatine with my prescription medications?
Generally yes — minimal documented interactions. Always disclose to your physician.