Creatine Monohydrate — The Cellular Energy Buffer

Creatine is naturally synthesised in the liver and kidneys and stored primarily in skeletal muscle as phosphocreatine. It functions as a rapid, reversible energy buffer, donating a phosphate group to ADP to regenerate ATP during periods of high cellular energy demand via the enzyme creatine kinase. By maintaining cellular ATP levels, creatine supplementation enhances cellular energy homeostasis, which is particularly critical in tissues with high fluctuating energy demands such as muscle and brain. In the context of aging, it may mitigate mitochondrial dysfunction and reduce oxidative stress, while also promoting muscle protein synthesis and satellite cell proliferation.

Creatine is one of the most extensively studied supplements in humans. Numerous randomised controlled trials and meta-analyses demonstrate that creatine supplementation, particularly when combined with resistance training, significantly increases lean tissue mass and upper and lower body muscular strength in older adults. Emerging evidence also suggests potential benefits for cognitive function and bone health in aging populations, though its primary proven efficacy remains in counteracting age-related sarcopenia and functional decline.

3–5 g/day is the standard maintenance dose, typically taken daily. A loading phase of 20 g/day (divided into 4 doses) for 5–7 days is optional for faster muscle saturation but not strictly necessary for long-term use. It can be taken at any time of day, though some evidence suggests taking it post-workout with carbohydrates may enhance muscle uptake.

Creatine monohydrate is widely considered safe and well-tolerated for long-term use in healthy adults at recommended doses. The most common adverse effect is mild gastrointestinal distress or water retention (intracellular fluid shift) during the loading phase. It is contraindicated in individuals with pre-existing renal disease, and those with impaired kidney function should consult a physician before use, although it does not cause renal damage in healthy individuals.

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