Some people who take creatine monohydrate supplements see a small increase in water inside their muscle cells, which shows up as a change in a special MRI scan — but only if their body actually responds to creatine.

Taking creatine supplements doesn’t change the acidity inside your muscle cells or the MRI signal from your muscles, even though other tests show something different.

Taking creatine powder for about a week—first a lot, then a little—can boost the amount of creatine in your muscles by over 13%, which helps your muscles store more energy.

Taking 20 grams of creatine powder a day for 5 days can make you gain about 1.2 kg in weight and help your muscles store more energy, at least in people whose bodies respond well to creatine.

Taking creatine for a week doesn’t make your muscles start building protein faster, even if you take a lot of it at first and then less later.

Even if creatine helps muscle cells survive under salty stress, it doesn’t do so by keeping their energy levels up—because the energy (ATP) still drops even when creatine is added.