Creatina, Creatina-Cinase, Creatinina e Suplementação: Aula para o Ensino Superior

In this lesson you will learn: 🕵️‍♂️ How we obtain creatine: Endogenous synthesis Most creatine is produced in the liver and kidneys, and in smaller quantities in the astrocytes of the central nervous system. It is formed from three amino acids: glycine, arginine, and methionine. After being produced, creatine is transported mainly to skeletal muscle, where about 90% of the body's stores are located. Exogenous route Creatine is also obtained through diet, mainly through: Red meat and fish. ⚡ Function of creatine The main function of creatine is to serve as a quick energy reserve, especially for muscles and the brain. It acts through the ATP-CP (ATP–phosphocreatine) system: Creatine receives a phosphate from ATP and becomes phosphocreatine. When ATP is used up and converted into ADP, phosphocreatine rapidly donates its phosphate to regenerate ATP. This allows for sustained effort, especially in short, intense activities. This system is essential for exercises lasting up to about 10 seconds. 🧪 Creatine Kinase The enzyme responsible for this phosphate exchange is creatine kinase (CK). There are three main isoenzymes: CK-MM: skeletal muscle, CK-MB: cardiac muscle, CK-BB: brain There are different versions of CK adapted to cellular compartments, including the mitochondria. Mitochondrial creatine kinase converts ATP into phosphocreatine, facilitating the transport of energy from the mitochondria to the cytosol—an extremely efficient mechanism. 🩺 Clinical Applications CK isoenzymes are used as markers of tissue damage: Elevated CK-MB in the blood → may indicate myocardial infarction Elevated CK-MM → indicates muscle damage, common in intense training or rhabdomyolysis In sports, CK dosage is used to assess: training load, recovery, and risk of overtraining. 🧴 Creatinine Creatine and phosphocreatine are spontaneously degraded to form creatinine, which is a metabolic waste product. Creatinine is eliminated by the kidneys. High blood levels may indicate kidney failure. Adequate levels in urine indicate good kidney function. 💊 Creatine as a Supplement Objective: To improve muscle energy availability in people who train. Proven Benefits: 5% to 15% increase in strength and power, greater training volume and intensity, and reduction of inflammation and muscle damage. Cognitive effects are still uncertain. How to take: Standard dose: 3 to 5 g per day. The time doesn't matter: the important thing is to take it daily. It can be ingested with carbohydrates to improve absorption. Loading protocol (optional): 20 g per day for 5 to 7 days, divided into 3 doses. Then maintenance of 3 to 5 g/day. Safety: Creatine is one of the most studied and considered safe supplements. Even higher doses have not shown consistent harmful effects, but people with kidney problems should seek medical advice before using it. Conclusion: Creatine is an essential molecule for the rapid supply of energy, naturally produced by the body and also obtained through diet. Supplementation makes sense mainly for those who train, bringing clear benefits for performance and muscle recovery. Leave a like and a comment, I always reply. Share the video, it helps me continue with this project. Become a member, or send a Pix payment to a friend: Pix key: [email protected] See you later!