Taking creatine while doing strength training leads to a small increase in overall body weight in adults, but this weight gain is not from fat—it comes from an increase in lean tissue like muscle.
Mechanism
Synthesis from 1 study
Creatine gives your muscles more quick energy so you can lift heavier and longer, which signals your body to build more muscle protein. The extra creatine also pulls water into your muscles, making them swell slightly. Together, this makes your muscles bigger and heavier without changing your fat...
Most probable mechanism
Taking creatine helps muscles recover faster between hard lifts by giving them more quick energy, which lets you do more work. This extra work triggers signals in muscle cells that tell them to build more protein, making the muscles bigger and heavier. The creatine also pulls water into the muscles, which helps these signals work better. Since fat doesn’t change, all the extra weight comes from muscle growth, not fat gain.
Oral creatine supplementation increases intramuscular creatine and phosphocreatine stores
Elevated phosphocreatine enables faster regeneration of ATP during high-intensity resistance exercise, increasing work capacity and mechanical tension on muscle fibers
Increased intracellular water content from creatine uptake creates an osmotic signal that enhances anabolic signaling pathways
Mechanical tension and osmotic stress activate the mTOR signaling pathway, upregulating ribosomal biogenesis and protein translation
Resistance training improves insulin sensitivity and upregulates creatine transporter expression, increasing creatine uptake and amplifying anabolic signaling
Increased muscle protein synthesis exceeds breakdown, leading to net accretion of contractile and structural proteins
Accumulation of muscle protein and associated water increases fat-free mass without altering fat mass
Evidence from Studies
Supporting (1)
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Creatine supplementation and resistance training: a comparison between novice and experienced lifters - a systematic review and dose-response meta-analysis
Contradicting (0)
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