Creatine: Who Does It Help, and How Should You Read the Research?
Creatine (in Hebrew spelled two ways, “קריאטין” and “קראטין”) is one of the best-established supplements for improving the ability to perform short, intense efforts and for supporting progress in resistance training. It is not a steroid. The body makes it, and it is also found in meat and fish. Supplementation can increase its stores in muscle, but the size of the response varies from person to person. ISSN position stand on creatine.
How does it work?
The creatine–phosphocreatine system helps regenerate ATP, a molecule used to transfer energy in the cell. Its importance stands out in short, intense activity and in repeated efforts. That does not mean you can train without fatigue: the supplement affects one particular component of the ability to produce energy, and does not remove the other factors that limit performance. Mechanism of action — ISSN.
For a strength trainee, the useful question is whether, over time, it becomes easier to complete quality training volume and progress in load. A feeling of “energy” right after drinking it is not a suitable test for creatine. In your training log, separate how you feel in a single session from a trend over weeks.
Strength, muscle mass and endurance
| Goal | How to read the evidence |
|---|---|
| Resistance training | There is a good basis for the supplement improving strength and lean mass alongside training |
| Repeated high-intensity efforts | There may be a benefit, for example in sprint sets |
| Prolonged continuous endurance | The direct benefit is less consistent; the added weight may be a consideration |
The evidence does not justify promising a fixed percentage of improvement for every user or every sport. A supplement tested in a sprint test does not guarantee the same improvement in a marathon. NIH review of supplements and performance.
Rapid weight gain at the start of use can reflect a change in body water. Measurements of “lean mass” also include water and are not the same as measuring new muscle protein. Over a resistance program, muscle growth may be added too, but a kilogram gained within days should not be read as a kilogram of muscle built. Review of common questions about creatine.
Dosage: do you have to load?
Two common ways to increase stores in healthy adults are:
| Approach | Example of a studied protocol | What it means |
|---|---|---|
| No loading | 3–5 g per day | Stores rise gradually over several weeks |
| With loading | About 0.3 g/kg per day, split into doses, for 5–7 days; then 3–5 g per day | Elevated stores are reached faster |
Loading is an option, not a requirement. These are research protocols for healthy adults, not individual guidance for children or people with underlying conditions. Dosing in the ISSN position stand.
For example, 0.3 g/kg for a person weighing 70 kg is 21 g for the whole day, not per dose. The calculation itself is not a reason to choose loading. Anyone who doesn’t need a rapid increase in stores can consider the gradual, simpler approach with a professional.
Which form to choose, and when to take it?
Creatine monohydrate is the most-studied form. There is no consistent evidence that more expensive forms are better. Nor is there solid grounds for “cycling” on and off in healthy adults using standard doses. Precise timing relative to training is less well established than the importance of taking it consistently over time. Review of myths and evidence.
When checking a product, ask how many grams of creatine are in a serving, how many servings are in the package and what the price per serving is. When creatine is part of a blend, don’t assume the weight of the scoop is the weight of the creatine. A 300 g package of pure creatine provides 60 servings of 5 g; a blend of the same weight won’t necessarily provide the same number of servings.
Kidneys, blood tests and side effects
In healthy adults, research at standard doses does not point to harm to kidney function. However, this should not be applied automatically to people with kidney disease. Supplementation may raise blood creatinine without necessarily indicating kidney damage, so tell your doctor about your use before the test is interpreted. Do not ignore an abnormal value or diagnose it yourself. Safety review.
Digestive discomfort is possible, mainly with large doses. Splitting doses may help. Kidney disease or a complex medical condition calls for professional guidance. ISSN position stand.
How to judge whether it’s worth it
Choose in advance a measure tied to your goal: reps at a fixed load, progress in your program or the quality of repeated efforts. Also record weight and digestive effects, especially if a weight class matters in your sport. Comparing just two sessions is sensitive to differences in sleep, load and motivation; a documented trend is a better basis for a conversation about continuing.
Athletes subject to drug testing should choose a product whose batch has been independently tested and verify the batch number. Such testing reduces the risk of contamination but does not eliminate it. AIS guidance on choosing supplements.
Frequently asked questions
Question: Do you need to take creatine on rest days too? Answer: With a daily protocol it is usual to continue on rest days too, because the goal is to maintain stores over time.
Question: Is the weight gain fat? Answer: The rapid gain at the start of use may be related to water. It alone cannot tell you about fat gain or muscle building.
Question: Does creatine replace protein powder? Answer: No. They are different things: protein powder supplies amino acids, while creatine works in the energy supply system for effort.
Further reading: Whey protein · Beta-alanine.
Updated September 8, 2026. This information is general and does not replace individual advice.