The Science
How Creatine Works: The Phosphocreatine System
Understanding creatine requires understanding how your cells produce energy — specifically, the ATP-PCr energy system.
ATP: Your Cellular Currency
Every action your body takes — from contracting a muscle fiber to firing a neuron — requires adenosine triphosphate (ATP). ATP is the universal energy currency of all living cells. However, your muscles only store enough ATP for approximately 2-3 seconds of maximal effort. After that, ATP must be regenerated — and the fastest way to do this is through the phosphocreatine (PCr) system.
The Phosphocreatine Shuttle
Here is the elegant biochemistry: When ATP is used for energy, it loses a phosphate group and becomes ADP (adenosine diphosphate). Phosphocreatine (PCr) — stored in your muscles — donates its phosphate group to ADP, regenerating it back into ATP. This reaction is catalyzed by the enzyme creatine kinase and happens almost instantaneously, without requiring oxygen.
PCr + ADP + H+ → ATP + Creatine
This reaction regenerates ATP in under a second — faster than any other energy system
By supplementing with creatine monohydrate, you increase the total amount of phosphocreatine stored in your muscles by 20-40%. More PCr = more rapid ATP regeneration = more reps, more power, more sustained high-intensity effort before fatigue. This is why creatine works — it directly expands your cellular energy buffer.
Wallimann et al., 2011 — Amino Acids; Kreider et al., 2017 — JCISSN
Beyond Muscle: Brain ATP
The phosphocreatine system is not exclusive to skeletal muscle. Your brain is one of the most ATP-hungry organs in the body, consuming approximately 20% of your total energy despite being only 2% of your body weight. Brain cells use the same PCr shuttle to regenerate ATP during intense cognitive work. This is why creatine supplementation improves cognitive performance — it increases the brain's energy reserve, particularly during demanding tasks, stress, or sleep deprivation. Research by Rae et al. (2003) demonstrated significant improvements in working memory and processing speed in healthy adults supplementing creatine.
Rae et al., 2003 — Proceedings of the Royal Society B; Avgerinos et al., 2018
Natural Creatine Sources
Your body synthesizes approximately 1g of creatine per day endogenously (in the liver, kidneys, and pancreas) from the amino acids arginine, glycine, and methionine. You obtain an additional 1-2g from dietary sources — primarily red meat and fish. However, cooking degrades some creatine content. Total daily creatine turnover in an average adult is approximately 2g/day, meaning your body uses and excretes about 2g daily (as creatinine in urine).
Beef (raw)
~4.5g per kg
Salmon (raw)
~4.5g per kg
Herring (raw)
~6.5-10g per kg
To get 5g of creatine from food alone, you would need to eat approximately 1.1kg (2.4lbs) of raw beef daily. Supplementation is the only practical way to achieve saturation-level creatine stores.
Types Compared
Creatine Types: Which Form Should You Buy?
The supplement industry sells dozens of creatine variants at premium prices. Here is the honest comparison based on actual research.
| Type | Evidence | Cost |
|---|---|---|
| Creatine Monohydrate | A+ | $ |
| Creatine HCl (Hydrochloride) | C | $$ |
| Buffered Creatine (Kre-Alkalyn) | C | $$$ |
| Creatine Ethyl Ester (CEE) | D | $$ |
| Creatine Magnesium Chelate | B- | $$ |
| Liquid Creatine | F | $$ |
Creatine Monohydrate
Evidence: A+The gold standard. Over 95% of all creatine research uses monohydrate. Highest evidence base of any sports supplement ever studied. Micronized forms dissolve more easily but are chemically identical.
The only form you need. Everything else is marketing.
Creatine HCl (Hydrochloride)
Evidence: CMarketed as more soluble and requiring lower doses. While it does dissolve better in water, no peer-reviewed study demonstrates it is more effective than monohydrate at equivalent doses. The 'lower dose needed' claim is unsubstantiated.
Overhyped. No advantage over monohydrate.
Buffered Creatine (Kre-Alkalyn)
Evidence: CClaimed to resist stomach acid conversion to creatinine. A 2012 study by Jagim et al. directly compared Kre-Alkalyn to monohydrate and found no difference in muscle creatine content, body composition, or performance. The pH-buffering claim does not translate to real-world benefit.
No advantage. More expensive for the same result.
Creatine Ethyl Ester (CEE)
Evidence: DMarketed as better-absorbed due to ester bond. Research by Spillane et al. (2009) found CEE actually degrades into creatinine faster than monohydrate, resulting in LESS creatine reaching muscle. Inferior to monohydrate.
Avoid. Worse than monohydrate by objective measures.
Creatine Magnesium Chelate
Evidence: B-Creatine bound to magnesium. Some preliminary data suggests comparable efficacy to monohydrate, with the added benefit of magnesium delivery. However, the research is limited and the cost premium is not justified when you can take monohydrate + magnesium separately.
Interesting but unnecessary. Buy them separately.
Liquid Creatine
Evidence: FCreatine is unstable in solution and degrades into creatinine over time. Pre-mixed liquid creatine products deliver significantly less active creatine than the label claims. Multiple studies confirm inferior results compared to powder monohydrate.
Avoid completely. Degraded before you drink it.
The Bottom Line
Buy creatine monohydrate. Specifically, look for "Creapure" on the label — this is a German-manufactured, pharmaceutical-grade creatine monohydrate with third-party purity testing. It costs $0.03-0.07 per serving. Every other form is a marketing exercise designed to charge more for the same (or worse) results. The ISSN, the world's leading sports nutrition research body, states: "Creatine monohydrate is the most effective ergogenic nutritional supplement currently available to athletes."
Practical Dosing
How to Take Creatine: Dosing Protocols
Creatine dosing is simple. The supplement industry has overcomplicated it. Here are all the protocols — and which one you should actually use.
Standard Daily Dose (Recommended)
Take 3-5g of creatine monohydrate daily, every day, indefinitely. No loading phase needed. Muscle creatine stores reach saturation within 3-4 weeks. This is the simplest, most practical, and best-tolerated approach. The ISSN (International Society of Sports Nutrition) endorses this as the primary recommendation.
Best for: Everyone. This is the default protocol.
Loading Phase + Maintenance
Divide 20g into 4 servings of 5g spread throughout the day for 5-7 days, then drop to 3-5g daily maintenance. This achieves full muscle saturation in under a week instead of 3-4 weeks. Useful if you need rapid saturation (e.g., before a competition). The downside: GI discomfort (bloating, cramping) is more common during the loading phase.
Best for: Athletes preparing for a competition within 1-2 weeks.
Body-Weight Adjusted
For individuals significantly above or below average body weight, adjusting dose to 0.03-0.05g per kg of body weight is more precise. A 60kg (132lb) person may need only 3g, while a 120kg (264lb) athlete may benefit from 5-6g. This accounts for the larger muscle mass (and thus larger creatine storage capacity) of bigger individuals.
Best for: Very large or very small individuals.
Cycling (NOT Recommended)
Some people cycle creatine (e.g., 8 weeks on, 4 weeks off). There is no scientific rationale for this. Creatine does not cause receptor downregulation, tolerance, or dependency. Your body does not 'get used to it' in a way that requires cycling. Stopping simply allows muscle creatine stores to deplete over 4-6 weeks, eliminating the benefit. Take it daily, year-round.
Best for: No one. This is a myth.
Practical Tips
- Mix creatine in any liquid — water, juice, protein shake. It is tasteless and odorless.
- Micronized monohydrate dissolves better than regular monohydrate (same molecule, finer grind).
- Taking creatine with carbs + protein may enhance uptake (insulin-mediated transport).
- Drink adequate water (2-3L daily). Creatine pulls water into muscle cells.
- Take it daily — including rest days. Saturation requires consistent intake.
Timing: Pre vs. Post Workout
Research shows timing is a non-issue once muscle creatine stores are saturated. However, if you want to optimize the marginal details:
Antonio & Ciccone, 2013 — JISSN