Creatine is one of the most common supplements athletes ask about to either gain muscle mass and/or improve athletic performance and recovery. Despite the overwhelming evidence of its safety, questions still remain on how it works and who should be taking it. In a recent article, the most common questions are addressed by experts and summarized below. Before the questions are answered, let’s review what is creatine and the benefits of supplementation. Defining Creatine Creatine is a compound produced in the body similar to amino acids, the building blocks of protein. It is primarily found in skeletal muscle (about 95%) and the remaining amount found in the brain and testes. Your body stores creatine as phosphocreatine (PCr) to be used for energy during high intensity exercise. Since about 1-2% of creatine is excreted in urine, the body needs to replace about 1-3 grams of creatine daily to maintain normal levels. Creatine is formed in the body from amino acids in the kidney and liver and about half of our creatine is from eating meat. For example, one pound (16 ounces) of uncooked meat provides 1-2 grams of creatine; placing vegetarians at risk for having lower muscular creatine stores compared to those who eat meat. Dosing Recommendations According to the International Society of Sports Nutrition (ISSN), creatine supplementation can increase muscle creatine and PCr by 20-40% by creatine loading, consuming 5 grams of creatine monohydrate (about 0.3 g/kg body weight), four times daily (20 g/day) for 5 to 7 days. Once muscle creatine stores are fully stocked, a maintenance dose of 3-5 g/day is suggested. Some other options are to consume creatine with carbohydrates and protein to promote greater muscle stores or to consume a lower dose 3 g/day for 28 days. It all depends on how quickly you desire to gain the benefits of supplementation and the timing of your sports performance. Ergogenic Benefits Potential sports enhancing benefits from taking creatine supplementation include enhancing short term exercise capacity and training, increased muscle strength and mass, and improving training quality and recovery. Creatine supplementation mainly benefits athletes performing high intensity power or strength type training such as sprints found in sports such as football, soccer, basketball, tennis, track or swimming sprints, lacrosse, power lifting and body building to name a few; however, benefits can also be found in endurance athletes as well. Creatine supplementation can also help athletes recover from intense training, when taking creatine with a post-exercise meal containing large amounts of carbohydrate (47-97 g) and protein (50 g) to enhance creatine retention. Furthermore, it’s been shown that creatine loading before exhaustive training can increase muscle glycogen storage than just eating carbohydrates alone. This would benefit endurance athletes performing muscle glycogen depleting training sessions longer than 90 minutes; as well as helping to reduce muscle damage from intense exercise as seen in marathon runners. Summary of Most Common Questions A full summary of all of the questions can be found in the 2021 article. The summary is evidence based and can be beneficial to review before considering creatine supplementation. 1. Does creatine lead to water retention? Water retention can happen in the early stages of supplementation but long term this does not result in total body water weight gain and should not cause water retention. 2. Is creatine an anabolic steroid? Creatine supplementation increases energy production during heavy anaerobic exercise like sprinting or weight training, increasing muscle power and performance. This does not mean it’s a steroid as seen with taking testosterone to promote muscle strength. They are similar but how they boost muscle gains have different chemical structures. Taking testosterone is also illegal without a physicians prescription; whereas, there are no legal ramifications taking creatine. 3. Does creatine cause kidney damage/renal dysfunction? After more than 20 years of research, there has been no studies to show creatine causes kidney damage. Overall there is risk with taking any supplement, and there is no valid link between taking creatine supplementation and compromising kidney health in healthy individuals. 4. Does creatine lead to dehydration and muscle cramping? There have been no studies to support that creatine supplementation causes dehydration or muscle cramping. 5. Is creatine harmful for children and adolescents? Use of creatine supplementation in adult athletes is well supported and proven to be safe, but data is limited in children and adolescents. The position stand in 2017 by the International Society of Sports Nutrition, states that younger athletes should optimize diet first, consider use only in athletes involved in serious/competitive supervised training, and to not exceed recommended doses. 6. Is a creatine ‘loading-phase’ required? Creatine loading is defined as supplementing 20-25 grams a day for 5-7 days, divided into four 5 g smaller doses. This is then followed by a maintenance dose of 3-5 g/day. Lower daily creatine supplementation dosing 3-5 g day is effective in increasing muscle mass, but it may delay maximum muscle creatine storage. It may take 28 days to achieve maximum muscular storage on a lower dose compared to loading, but it all depends on how quickly you are hoping to maximize the potential of creatine supplementation. 7. Is creatine beneficial for older adults? As we age we lose muscle mass and strength. Creatine supplementation can greatly benefit master athletes to delay fatigue and increase muscle mass and strength. However, supplementation alone without resistance exercise is not going to show the benefits; therefore, older athletes will enhance sports performance and muscle recovery combining creatine supplementation with exercise. 8. Is creatine only useful for resistance /power type activities? Creatine supplementation has been shown to not only benefit athletes performing high-intensity/power type activities, but may also provide benefits to endurance athletes as well. Combining creatine supplementation with carbohydrate and protein can promote greater muscle glycogen storage than just carbohydrate supplementation alone. This can promote muscle recovery and reduce muscle damage from intense exercise as well. It's important to remember that sports nutrition supplements are not regulated by the FDA and you should consult your physician or certified sports dietitian before starting any supplement. If you do choose to use creatine supplements, choose ones that are 3rd party certified by either NSF Sport, Informed Choice, or USP.