Insulin enhances creatine uptake by upregulating Na⁺/K⁺-ATPase activity and increasing skeletal muscle perfusion, thereby strengthening the sodium gradient and improving nutrient delivery.

Study: GLP-1 and Insulin Recruit Muscle Microvasculature and Dilate Conduit Artery Individually But Not Additively in Healthy Humans

The study shows insulin increases blood flow to muscles, which can help deliver nutrients, but it doesn’t test whether insulin helps muscles take up creatine specifically.

Study: Insulin-mediated muscle microvascular perfusion and its phenotypic predictors in humans

The study shows that insulin increases blood flow to muscles, which helps deliver nutrients better. This supports the idea that insulin helps muscles take in more nutrients like creatine.

Study: Carbohydrate ingestion augments creatine retention during creatine feeding in humans.

The study shows that when people take creatine with sugary carbs, their bodies keep more of the creatine, likely because insulin helps muscles absorb it better.

Study: Insulin induces translocation of the alpha 2 and beta 1 subunits of the Na+/K(+)-ATPase from intracellular compartments to the plasma membrane in mammalian skeletal muscle.

The study shows that insulin helps move more sodium-potassium pumps to the surface of muscle cells, which supports the idea that insulin can boost the cell’s ability to take in nutrients like creatine.