If young, healthy guys take sugar supplements for 5 days, their muscles store more energy, but taking creatine doesn’t do the same — so sugar seems to fill up muscle fuel better than creatine when not working out.

Taking creatine for 5 days doesn’t boost muscle fuel stores in healthy young guys who aren’t working out or eating extra carbs — it needs more than just the supplement to make a difference.

If young, healthy guys take 20 grams of creatine every day while eating a super high-carb diet after intense exercise, they rebuild their muscle fuel 82% faster in the first day compared to just eating high carbs alone.

Taking creatine for five days boosts creatine in muscles, but doesn’t change how much glycogen (energy) is used during intense cycling in healthy young guys — so more creatine alone doesn’t help save energy stores during endurance workouts if muscles weren’t already drained.

Creatine might help your muscles store more glycogen, but only if you first do a workout that drains your energy stores — otherwise, it doesn’t do much for glycogen.

For young, active guys taking creatine, adding carbs doesn’t seem to make it work better for boosting power, strength, or stamina—even though we thought insulin from carbs might help the body absorb more creatine.