Scientists still haven’t figured out the way that Creatine boosts muscle mass and strength. Creatine is a nitrogenous organic acid that is found in the muscle tissue of vertebrates mainly in the form of phosphocreatine and supplies energy for muscle contraction. Using Creatine help you increase your reps by providing you ATP, which is fast energy. Creatine may influence genes in muscle cells that cause them to grow in size. Creatine causes the body to retain water; you’re likely to lose weight when you stop taking Creatine, as your body flushes out the extra fluid.
Creatine is a natural nutrient found in our bodies. Approximately 95% of the body’s Creatine supply is found in the skeletal muscles. The remaining 5% is scattered throughout the rest of the body, with the highest concentrations in the heart and the brain. You can find Creatine in red meats and fish.
The side effects of Creatine, diarrhea was the most commonly reported adverse effect of Creatine supplements, followed by muscle cramping. Some have shown kidney, liver, and blood functions were not affected by short-term amounts or long-term lower amounts in healthy young adults. You will feel stronger, more powerful, and will have much more energy during your workouts. You will start to notice that your muscles will become fuller and bigger due to some water retention, and mostly gain in muscle mass. When you exercise intensely, you’ll find that the pain won’t bother you nearly as much. You’ll have noticeably more energy and bursting power during workouts. It can cause kidney stones in some rare cases.
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Personally I'm a Creatine user. I've found that the most expensive name brands of it work the same as the cheapest of brands. I've also done my share of looking up negative effects. All I've personally observed is the diarrhea side effect. :)