What does creatine do

1. Why athletes and trainers keep reaching for creatine: the energy‑engine explanation

Creatine functions as a fast‑acting phosphate donor in muscle cells, increasing phosphocreatine stores and enabling quicker regeneration of ATP during short, intense efforts; that biochemical role explains why creatine supplementation consistently boosts sprint, power, and repeated‑effort performance and enhances strength gains when paired with resistance training ^{[1] [2]}. Clinical and review summaries emphasize that approximately 95% of body creatine resides in skeletal muscle, and raising intramuscular creatine stores through supplementation directly improves maximal strength, work output, and recovery between bouts of high‑intensity exercise, which is why professional sports, military training, and recreational lifters widely use it ^{[1] [2]}. Some sources also note creatine helps glycogen storage and may offset age‑related muscle loss when combined with exercise, but it does not act as an anabolic hormone; improvements occur through enhanced energy availability and training response ^[5].

2. The brain angle: emerging benefits and limits for cognition and disease

Multiple reviews and media summaries point to potential cognitive benefits of creatine supplementation, including improved memory, attention, and resilience to mental fatigue in some groups, and preliminary signals for therapeutic roles in depression, traumatic brain injury recovery, and neurodegenerative conditions like Alzheimer’s disease, though clinical evidence is mixed and often preliminary ^{[3] [6]}. Health overviews emphasize plausible mechanisms — creatine’s role in cellular energy metabolism applies to neurons as well as muscle cells — but many neurology applications remain investigational, with small trials and variable endpoints; experts urge cautious interpretation until larger, well‑controlled studies confirm efficacy and safety across age groups and disease stages ^{[4] [3]}. Consumer‑oriented accounts sometimes overstate promise, so an evidence‑hierarchy view matters: strong, consistent performance effects in sport versus conditional, evolving signals in brain health ^{[2] [3]}.

3. Safety profile and dosing: common guidance and notable caveats

Systematic reviews and institutional overviews commonly recommend 3–5 grams per day for adults as an effective and well‑tolerated maintenance dose, with short‑term loading strategies used in some protocols to saturate muscle stores more rapidly ^{[3] [5]}. Most healthy adults tolerate creatine without serious adverse effects; reported minor issues include gastrointestinal upset, weight gain from water retention, and rare complaints of cramps or dehydration, while long‑term studies in healthy populations have not shown widespread kidney harm, but people with pre‑existing renal disease should consult a physician before use ^{[5] [1]}. Sources differ in emphasis: academic reviews stress evidence‑based dosing and monitoring, whereas public pieces highlight convenience and broad safety, so clinicians must weigh individual risk factors, medication interactions, pregnancy/breastfeeding status, and limited pediatric long‑term data ^{[5] [4]}.

4. What creatine is — biochemistry and dietary context

Creatine is synthesized endogenously from the amino acids arginine, glycine, and methionine and is also obtained from dietary sources like red meat and seafood; it is not technically an amino acid itself but a nitrogenous compound that participates in cellular energy buffering ^{[5] [7]}. Because normal diets supply variable creatine amounts and endogenous synthesis declines slightly with age, some individuals — particularly strict vegetarians or older adults — show lower baseline muscle creatine stores and may experience more pronounced performance and cognitive benefits from supplementation, a pattern documented in both clinical summaries and controlled trials ^{[5] [1]}. This biochemical framing explains why supplementation has an outsized impact in short‑duration, high‑power activities and why dietary context matters when predicting individual response ^{[1] [4]}.

5. Open questions, competing narratives, and practical takeaways

Key uncertainties remain around long‑term effects in children, adolescents, pregnancy, and those with chronic illnesses, and while meta‑analyses support athletic benefits and suggest neurological promise, some disease‑specific claims (for ALS, Huntington’s, or low bone mass) lack convincing evidence and require more rigorous trials ^{[1] [6]}. Reporting from consumer outlets sometimes amplifies early positive findings, creating an optimistic narrative that outpaces clinical consensus; conversely, conservative medical reviews emphasize safety monitoring and individual risk assessment, reflecting a balance between practical utility for performance and prudence for medical uses ^{[3] [5]}. For most healthy adults seeking strength, a 3–5 g daily regimen combined with resistance training is evidence‑backed; for therapeutic uses, consultation with a healthcare provider and review of current clinical trials is essential ^{[5] [3]}.