Creatine monohydrate: strength, power and cognition

Creatine monohydrate is among the most extensively studied dietary supplements in the history of sports science. The International Society of Sports Nutrition (ISSN) in its position paper states: it is the most effective ergogenic nutritional supplement for increasing high-intensity exercise performance and lean body mass gains when combined with resistance training (Kreider et al., 2017). Yet the supplement is frequently demonized or credited with properties it does not have. Let's examine what the latest data actually show.

How does the phosphocreatine system work?

Muscle contraction requires ATP — the molecule that serves as the immediate fuel for all cellular work. During brief explosive efforts — a sprint, a heavy set in the gym, a jump — ATP stores in muscle tissue are depleted within seconds. This is where phosphocreatine steps in: it donates its phosphate group to ADP, regenerating ATP far faster than glycolysis or oxidative phosphorylation can.

Taking creatine monohydrate raises intramuscular phosphocreatine stores, expanding the "power buffer" during short, intense efforts. This is the biochemical basis of the supplement's athletic effects.

Strength and power: what do 69 RCTs show?

In 2025, a systematic review and meta-analysis of 69 randomized controlled trials (1937 participants aged 18–74) was published in the journal Nutrients. The authors found statistically significant effects from creatine intake combined with training:

• bench press / chest exercises: WMD = +1.43 kg (p = 0.002);
• squat: WMD = +5.64 kg (p = 0.001);
• vertical jump: WMD = +1.48 cm (p = 0.01);
• Wingate peak power: WMD = +47.81 W (p = 0.004).

The magnitudes are moderate but reproducible and statistically robust across a large sample. Critically, the supplement shows an effect only in combination with training — without the stimulus, there is no mechanism for strength gains.

Does creatine affect cognition?

Alongside the athletic data, the evidence base for cognitive effects is growing. A meta-analysis by Xu C., Bi S., Zhang W. and Luo L. (Frontiers in Nutrition, 2024) pooled 16 RCTs with 492 participants aged 20 to 76. Results:

• memory: SMD = 0.31 (95% CI: 0.18–0.44) — statistically significant improvement;
• information processing speed: SMD = −0.51 (95% CI: −1.01 — −0.01) — significant acceleration;
• attention task completion time: SMD = −0.31 (95% CI: −0.58 — −0.03) — significant improvement.

Overall cognitive function and executive function showed no significant aggregate effect. Effects are most pronounced in adults aged 18–60; data for individuals over 60 are limited. Women showed more pronounced processing speed acceleration than men.

The mechanism of cognitive effects is likely linked to the role of the phosphocreatine system in neuronal energy metabolism: the brain consumes a substantial amount of ATP, and increasing the brain's phosphocreatine pool may support neuronal performance.

Safety: what does ISSN say?

The ISSN position paper of 2017 (Kreider et al.) concluded: in healthy individuals, intake of up to 30 g/day for up to 5 years was not accompanied by clinically significant impairment of kidney or liver function in any of the studies reviewed. The document covers data across several populations — from athletes to the elderly and patients with neurodegenerative diseases.

An important caveat: people with pre-existing kidney disease should consult a physician before starting supplementation. For healthy individuals at standard doses, there are no safety concerns.

How to take it: two evidence-based protocols

Data support two equally effective approaches:

• Without a loading phase: 3–5 g of monohydrate per day, daily. Muscle saturation is achieved in 3–4 weeks — slower, but the end result is the same.
• With a loading phase: 20 g/day (4 doses of 5 g) for 5–7 days, then a maintenance dose of 3–5 g/day. Saturation is accelerated to 5–7 days; the final outcome does not differ.

The timing of intake relative to training does not have a meaningful impact on results. The key factor for effectiveness is daily consistency: missed doses reduce muscle phosphocreatine stores.