ISSA, International Sports Sciences Association, Certified Personal Trainer, ISSAonline, Nutrition, Creatine Supplements for Exercise: What You Need to Know


Creatine Supplements for Exercise: What You Need to Know

Reading Time: 6 minutes 13 seconds


Date: 2021-02-09T00:00:00-05:00

Athletes are on the never-ending quest to run faster, jump higher, and beat out the competition. The hunt for a competitive edge is on. Many athletes are turning towards performance-enhancing supplements. Creatine is one of the most popular performance supplements.

If your clients have been asking about supplements—creatine in particular—here's what you need to know. And keep in mind that as a personal trainer, you may not be able to provide nutrition advice. Be sure you understand your scope of practice and refer clients to their doctor as necessary.

What is Creatine?

Creatine is an amino acid created by the liver, pancreas, and kidneys. Additionally, foods such as seafood and red meat contain creatine. About 95% of the body's creatine is stored in skeletal muscle. A small percentage of this creatine is stored in skeletal muscle as free creatine. A larger percentage is stored as creatine phosphate.

Creatine phosphate is a form of stored energy within the cells of the body. It helps to produce a high energy molecule known as adenosine triphosphate (ATP). ATP is the body's main energy currency. ATP is needed for biochemical reactions involved in muscle contractions. As muscles perform more work, more ATP is consumed and must be replaced.

How Does Creatine Work to Improve Performance?

The energy required to make ATP during and following exercise is largely dependent on the amount of creatine phosphate available in the body's skeletal muscles. Depleted creatine phosphate leads to diminished energy availability. This is because the body is unable to resynthesize ATP at the rate required to sustain high intensity exercise. As a result, depleted creatine phosphate leads to the inability to maintain maximal effort during exercise, and performance declines.

Creatine supplementation may help improve exercise performance in high intensity, short duration exercise. Increasing consumption of creatine increases overall muscle creatine content. This increased muscle creatine may thereby increase the availability of creatine phosphate. More creatine phosphate allows for an accelerated rate of ATP re-synthesis. Essentially, the body can restore energy stores faster. More energy means enhanced volume and quality of work performed.

Creatine is one of the best supplements for improving muscular strength and high intensity exercise performance. Typically, ATP stores become depleted within 8-10 seconds of high intensity activity. Creatine supplementation allows the body to produce more ATP. This allows an athlete to maintain optimal athletic performance for longer. Bottom line, increased creatine allows for an increased capacity to produce ATP. More ATP means more energy output and overall increased work output during exercise.

Creatine may also aid the body in muscle gain by:

  • Increasing workload: Increased creatine stores allows for more total work volume. This is most notable in short duration high intensity exercise such as resistance training or sprint intervals.

  • Improving cell signaling: Creatine increases satellite cell signaling. Satellite cells are muscle stem cells involved in muscle growth. They are also important in muscle regeneration. Therefore, creatine supplementation may aid in muscle repair and muscle growth.

  • Raising anabolic hormones: Creatine supplementation may increase insulin like growth factor (IGF-1). IGF-1 has anabolic effects in adults, meaning it aids in the building processes. Anabolic hormones help build muscle mass following resistance training.

  • Increasing cell hydration: Creatine draws increased water content into the body's muscle cells. This increased cell volume has a positive effect on overall muscle growth.

  • Reducing protein breakdown: Creatine supplementation may aid in increasing overall muscle mass by reducing muscle breakdown.

  • Lowering myostatin levels: Myostatin is a protein that inhibits muscle cell growth. Supplementing with creatine may reduce myostatin levels. This would increase potential muscle mass growth during resistance training.

ISSA, International Sports Sciences Association, Certified Personal Trainer, ISSAonline, Nutrition, Creatine Supplements for Exercise: What You Need to Know, Creatine

Creatine Dietary Supplement Forms

Not all creatine supplements are created equal. It is important for your clients to be aware of what is in the supplements they take. Many supplements on the market have extra junk in them and are often more expensive.

The most common and well-researched creatine supplement is creatine monohydrate. It is usually very affordable and is supported by hundreds of studies as safe and effective.

Some brands may add additional ingredients such as electrolytes. Alternatively, some people buy pure creatine powder and mix it with fruit juice, aiming for about 70 grams of simple sugars for every 5 grams of creatine. The carbohydrates in fruit juice will raise insulin levels. This helps increase maximum creatine uptake into the muscles.

Not all supplements on the market are of equal quality. Mixing creatine powder with juice or water is a common way to assess the quality of the powder. The powder quality is poor if it is hard to dissolve and leaves residue at the bottom of the glass. Ideally, the consumer would want the creatine monohydrate in their muscles, not at the bottom of their glass.

Creatine supplements are also found in pill form. The amount of creatine within a single pill is rather small. Because of this, you would need to take a large volume of pills, especially during the loading phase to consume an effective dosage.

Supplementation Protocol

Supplementation typically begins with a creatine loading phase. This creatine loading phase leads to a rapid increase in muscle creatine stores. During the loading phase, your client would take about 20 grams of creatine for 5-7 days. This would be split into 4 servings of 5 grams throughout the day.

Absorption can be maximized by consuming creatine with a carbohydrate-based meal. Carbohydrates trigger the release of insulin which will maximize creatine absorption. Without the creatine loading phase, it may take up to 3 or 4 weeks to maximize creatine stores. If a client foregoes the loading phase, they would simply start by consuming 3-5 grams of creatine per day.

Following the loading phase, is a maintenance phase. During this phase, athletes consume 3-5 grams of creatine per day. This ensures maintenance of high levels of creatine within muscle stores. There has been no proven benefit shown for creatine cycling. Therefore, athletes can stick with this dosage for a long time.

Safety, Side Effects, and Downfalls

Creatine monohydrate is one of the most well-researched supplements on the market. There has been some speculation as to the safety of creatine on the liver and kidneys. However, no studies have evidenced harm to liver or kidney function in healthy adults taking normal doses. Individuals with pre-existing kidney and liver problems should consult with their doctor before considering creatine supplementation.

Some individuals have reported dehydration and cramping with creatine supplementation. However, research has not supported this link. In fact, some studies suggest creatine supplementation may reduce cramping and dehydration for endurance athletes.

Most side effects reported are speculation and may not necessarily be true or reliable. Reports of kidney damage, blood sugar concerns, heart problems, muscle cramps, dehydration, and diarrhea have been noted. However, there is no published literature indicating creatine supplementation is unsafe.

Creatine supplementation is not suggested for individuals under the age of 18. Those under this age are still growing. Research is not 100% sure of the impact that creatine supplementation may have on muscles and bones as they grow. Because of this, it is best to avoid supplementation until adulthood. This means creatine supplementation is not suggested for high school athletes or those still maturing and growing.

While there are no major safety concerns with creatine supplementation, there are a few downfalls to consider. Creatine supplementation is likely to result in weight gain. Creatine pulls more water into your muscles. Individuals may gain around 2 to 4 pounds of water retention within their first week of supplementation. This may be viewed as a downfall to some and a bonus to others. The increased water in muscle tissue makes muscles look bigger and fuller. However, if weight loss is the main goal, it is important for clients to understand creatine supplementation may cause water weight gain.

Creatine Supplements for Exercise

Creatine is not a magic pill. The bottom line is that creatine increases the body's capacity to produce ATP. More energy equals increased work capacity. However, clients still must put in the work.

Creatine supplementation may have a different effect on everyone. Clients should consult their doctors before significantly changing their diets and supplements. Some individuals simply don't respond genetically. Those who already eat a creatine rich carnivore diet may see less noticeable improvements compared to vegans or vegetarians not eating creatine rich foods on the regular.

Fewer benefits have been shown for supplementation with endurance athletes. Endurance exercise is typically performed at a lower intensity. It relies less on the rapid ATP regeneration compared to short duration high intensity exercise. This makes creatine's role less significant in endurance exercise. But for those looking to boost their energy and work capacity in short duration, high intensity workouts creatine supplementation may be just the ticket. Just remember that creatine alone won't make them bigger faster and stronger. Encourage them to train hard, put in the work, and trust the process.

Interested in learning more about nutrition and supplementation to maximize performance? Check out the ISSA's Nutritionist course. You'll learn how to bridge the gap between teaching clients WHAT to eat and HOW to make it a healthy and doable lifestyle that supports their fitness goals.

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By becoming an ISSA Nutritionist, you'll learn the foundations of how food fuels the body, plus step by step methods for implementing a healthy eating plan into clients' lifestyles.

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