Creatine Supplement Guide

Creatine is the backbone of climbing’s most important energy system. But are you getting enough, and how do you know?

The following article originally appeared on ClimbingNutrition.com. Whether you’re looking for help sorting through supplements, need advice on how to fuel yourself for your project, or just want some general tips for using nutrition to stay fit and healthy in your sport, Climbing Nutrition is the place.

Facts at a Glance: Creatine

Summary Creatine greatly improves strength, power, and power endurance, making it an ideal supplement for sports climbers and boulderers alike. These benefits also apply to training, and will enable greater training gains over time. Related to power endurance, creatine will reduce the pain and fatigue associated with getting pumped by increasing blood flow (which superficially increases the “pumped” sensation).

Best For…Bouldering ★★★ Sport Climbing ★★★ Training ★★★

DosageFirst Week—300 mg/kg (136 mg/lb) divided into 2-4x Doses per Day Second Week +—100 mg/kg (45 mg/lb) divided into 2 Doses per Day (1 tsp = 3.6 g)

Adverse Affects Weight Gain—Creatine typically causes a roughly 1-2.5% increase in weight, depending on current muscle creatine levels.

Disclaimer

In this supplement guide, it’s very likely I am going to challenge beliefs you may have about creatine and climbing. I have spent hours collating and synthesizing research into this review of the benefits and drawbacks of creatine to climbers, and based on that research I can say that creatine is probably the most effective ergogenic supplement available to climbers. Once you’re done reading, I think you’ll agree.

What Is Creatine?

Simply put, creatine is the backbone of climbing’s most important energy system: the creatine phosphate system, also known as the phosphagen system. When our muscles expend ATP (cellular energy), the phosphate group attached to creatine phosphate can be donated to the spent ADP molecule in order to regenerate it back to ATP and allow work to continue. During rest, our muscles restore the used-up creatine back to creatine phosphate with spare aerobic energy.

Of the three energy systems our body uses, the creatine phosphate system has the greatest capacity for energy regeneration and is therefore the most capable of powering bursts of high intensity activity. Creatine can regenerate ATP about 2x faster than anaerobic carbohydrate oxidation, 4.5x faster than aerobic carbohydrate oxidation, and 11x faster than fat oxidation1

Unfortunately, the creatine phosphate system is also our most limited energy system, and can only provide about 5-7 seconds of energy in any given spurt. Thankfully, the nature of climbing allows for many “micro-breaks” (e.g., easy sections, rests on good holds, and even the times when you let go for just a second before grabbing the next hold) that allow creatine to be continually regenerated. As a result, an estimated 40% of the energy used to climb comes from creatine, and another 40% comes from the aerobic system whose hypothetical purpose in climbing is mostly to regenerate creatine to creatine phosphate.2 Thus, we could estimate that upwards of 80% of the energy used during a difficult climb either directly or indirectly revolves around creatine phosphate (while the rest comes from anaerobic carbohydrate oxidation).*

*80% is a very loose figure. We have a single study that estimates that around 40% of the energy comes from the creatine phosphate system and another 40% comes from the aerobic system, but that is all. To really be certain, we need some replication, preferably with a larger group. Furthermore, we can only hypothesize about how much of that aerobic energy was spent regenerating ATP—some of it almost certainly was spent just supplying energy for climbing, though really most difficult climbs (difficult being relative to each person) will have far too great of energy demands to derive any significant amount of energy from such a slow system as aerobic respiration. So please understand that my 80% figure is mostly indicative of the general importance of the creatine phosphate system, and that the actual figure will vary from person to person and route to route.

What Creatine Is NOT

No doubt in part because of its vast popularity, creatine has become host to a number of myths and rumors (both positive and negative). It’s important to recognize them for the falsehoods they are, so here I debunk some of the most common and harmful myths—the ones that are repeatedly touted as evidence for why you shouldn’t take creatine yet hold no truth.

Creatine Is NOT a Steroid Creatine is not a hormone, so by definition it cannot be a steroid. Steroids are fat-soluble, complex hormones derived from cholesterol, while creatine is a water-soluble compound derived from the amino acids glycine and arginine.

Creatine Is NOT Bad for the Kidneys Creatine has no reported toxicity and all excess creatine is easily broken down into creatinine, which is excreted in the urine. No studies corroborate the myth that extra creatinine stresses or harms the kidneys,3,4 and currently the only group warned to take caution are those who already have kidney problems and thus may have impaired kidney function.

Creatine Does NOT Cause Cramps or Increase Rate of Injury No evidence suggests creatine causes cramps or increases the rate of injury.5 In fact, the opposite might be true—in at least one study, football players who supplemented with creatine suffered fewer cramps and injuries than non-supplementers.6

Creatine Is NOT Dehydrating Again, the opposite is actually true. Since creatine reliably increases muscle water content, it can help improve bodily temperature control and overall hydration, thereby also improving comfort in the heat (if not performance).7–11

Creatine Is NOT Unethical or “Unsporting” Our body naturally produces small amounts of creatine (1-2 grams a day), and those who eat meat or fish will typically consume at least another gram. Vegetarians and vegans typically have lower levels of creatine and have the most to benefit from supplementation.12,13 Creatine supplementation levels the playing field for everyone, regardless of their diet, and is no more unsporting or unethical than any other nutritional intervention that improves performance.

Creatine Is NOT a Banned Substance Creatine is not banned for use in any competitive sport, including rock climbing. Both the IFSC (International Federation for Sport Climbing) and the IOC (International Olympic Committee) recognize the legality of creatine supplementation14,15

What Are the Benefits of Creatine?

Creatine supplementation can boost creatine levels by 20-50%,16–18 and also increases the rate of phosphocreatine resynthesis.19 This directly increases the energy available for high-intensity exercise and leads to numerous downstream benefits, including…

Increased Strength and PowerCreatine significantly increases strength and power for anaerobic activities (such as climbing).20–30  A review of the research concluded that creatine improved strength by roughly 20% compared to only 12% in placebo groups.28

“But wait!” you say, “we climbers are more concerned with our strength-to-weight ratio than any absoluteincrease in strength, and creatine also causes weight gain!” True, creatine does cause a small amount of weight gain—approximately 2-5 lbs for most people, depending on their current weight (more muscle, more weight gain) and muscle creatine level, or about a 1-2.5% increase in weight—but this small amount of weight gain is dwarfed by the significantly greater increases in strength (even when you consider only the strength of the forearms).31,32

I will admit that there is a lot more to know on exactly how creatine affects strength-to-weight ratio as far as climbing is concerned—but the only way we’ll learn this is through studies on creatine use in actual climbers. It’s possible that creatine does not significantly improve the strength of smaller muscle groups like the forearms, as one study suggests,33 though it will still dramatically increase the strength and power of other groups that are at least as important such as those of the back, shoulder, and upper arms.

Increased Power EnduranceCreatine supplementation will significantly boost your power endurance,33–39 and this time the research specifically includes small muscle groups like the forearm flexors.33,35 Specifically, in one study creatine boosted time-to-fatigue during a handgrip exercise by an average of 18% across repeated trials (compared to placebo),33 and in a second study creatine supplementation boosted maximal grip power across 10 seconds by 15% (again compared to placebo).35

Decreased PumpTo the contrary of anecdotal reports about creatine increasing the pumped sensation, scientific evidence actually suggests creatine should help you resist getting pumped.

Briefly put, a climber gets pumped when muscle acidity starts becoming too great and the arms start to burn. One physiological response to this (and exercise in general) is a swelling of the muscle tissue (the “pump”), but this is actually a beneficial response as the swelling is caused by the dilation of blood vessels and capillaries in order to provide the muscle with more oxygen. Thus, even though pain and fatigue usually accompany tight, swollen forearms, the swollen forearms are actually an adaptive response to help increase energy availability and decrease pain and fatigue.

Creatine fights the part of the pump climbers actually dislike—the pain and fatigue part—by increasing the adaptive response. Compared to a placebo, creatine can increase blood flow to the forearms by a whopping 38%,40 allowing far more oxygen to be supplied and also for better clearance of metabolic byproducts like ammonia and lactate. Creatine also increases the “relaxation velocity” of the forearm muscles,41 or how fast the muscles can relax after being contracted and start to re-oxygenate. Relaxation velocity could be a critical factor to climbing performance, and one study hypothesized that a primary difference between elite climbers and non-climbers is improved speed of forearm re-oxygenation after releasing a hold.42

Creatine also acts a buffer against increasing muscle acidity by absorbing H+ ions (the cause of intramuscular acidity) in order to regenerate used creatine to creatine phosphate. Greater creatine resynthesis rates mean greater buffering capacity, as well, and in this way helps prevent muscle pH from dropping in the first place.

So it makes sense why some people report that creatine actually makes their pump worse—creatine does cause the muscles to swell more, causing the tightness we associate with being pumped. But this is actually a good thing because it means your muscles are being better oxygenated and will be better able to resist the pain and fatigue part of being pumped. Remember, creatine has been shown to significantly increase power endurance—meaning it reliably increases the amount of time you can hold onto something before failing—which implies creatine is doing a rather good job of preventing pump-related fatigue, not increasing it.

Adverse Effects

Creatine is extremely safe, with no toxicity or side effects capable of producing harm. There are potentially a couple adverse effects specific to climbing, however:

Increased Weight Creatine does reliably increase weight in users, usually by about 2-5 lbs in the beginning (it can also cause further weight gain down the road by improving your ability to build lean muscle, but this should really not be viewed as a bad thing). All of this initial weight gain is “water weight”, as creatine pairs with water when it is stored in the muscle.

As discussed earlier, the gains in strength and power (as well as power endurance) vastly outweigh any increase in weight—but nonetheless, a climber who begins supplementing with creatine should expect to gain a few pounds in the first week.

You might hear anecdotal reports of how creatine won’t cause weight gain if you take a small enough dose. Unfortunately, these reports are patently false. Creatine either works and causes you to gain a little water weight, or it doesn’t work and you don’t gain any weight—there’s no third option. If your muscle creatine stores increase (which is the goal), then your muscle water content will also increase to accommodate that extra creatine and so will your weight. Period.

Also note that the increased water weight is not necessarily a bad thing as it can potentially help buffer your core body temperature against increases.7–11 In certain conditions, core temperature could limit your ability to climb by increasing perceived exertion.43

Decreased Range of MotionSince creatine can increase intramuscular water content, it can potentially also decrease range of motion. There is not a lot of research on this, but one study did suggest that creatine could decrease range of motion for shoulder extension, shoulder abduction, and ankle dorsiflexion.44 The same study found no change to the range of motion for either the hips or the elbows.

How important is this impaired range of motion to climbers? Not important at all. Two studies that looked at how important flexibility was to climbing both found that only hip flexibility had any impact.45,46 Shoulder flexibility, the joint most significantly affected by creatine, did not affect climbing performance. Thus, even though creatine could slightly impair your flexibility, it will not do so in a meaningful way to a climber.

Dosage

It’s common to divide creatine into two phases: a loading phase (the first week) and a maintenance phase (after the first week). The loading phase quickly increases muscle creatine levels to their max capacity, and the maintenance phase simply keeps those levels at max.

Some people skip the loading phase in an effort to avoid weight gain (again, this does not work) and use the maintenance phase dose from day one to slowly build muscle creatine levels. Speaking long-term, there is no difference between the two protocols—but it will take around a month (as opposed to a week) to build muscle levels up to their maximum potential. Thus, I recommend using the loading protocol as you will get results faster.

Week 1 (Loading Phase)300 mg per kg bodyweight (136 mg per lb), divided into at least 2 doses and as many as 4.

Week 2 & On (Maintenance Phase)100 mg per kg bodyweight (45 mg per lb), divided into 2 doses.

Ideally, if you train or climb on a given day, you should take one dose directly after your climbing session with some protein and carbohydrates because insulin will help push the creatine into the muscle cells. This is ultimately of less importance than simply getting the right dose, however, so focus on that first.

Some people insist you should “cycle” creatine, meaning that you take it for a period and then stop for about awhile before resuming. There is no evidence this is effective or worthwhile. If you cease using creatine, your levels will gradually return to baseline and you will lose its benefits (though not the gains you made while training). On the other hand, you will continue to experience the benefits of creatine for as long as you take it, which means you can continue to climb and train hard.

(And don’t worry, as mentioned earlier there is no risk associated with long-term creatine use.4)

How to Choose the Right Product

As with other supplements, many manufacturers put creatine into pre-formulated pre-, peri-, and post-workout mixes. I’m really not a fan of these sorts of mixes because they are impossible to measure out to your own needs—you get the ingredients in whatever proportion the manufacturer has decided. Therefore, as usual, I recommend you choose a “pure” supplement—one that is just creatine.

The second thing you need to consider is the type of creatine, as there are a few options on the market. Hypothetically, all should work the same given enough time—but creatine monohydrate has by far the best evidence for efficacy. Creatine monohydrate is also the cheapest formulation, so do your best to avoid falling for ads for “designer creatines” (like creatine pyruvate, creatine citrate, and Kre-Alkalyn) that are at best equally as effective, at worst far less effective, and always far more expensive.

This third thing to consider is whether the supplement manufacturer you are considering is trustworthy. An unfortunate fact of the sports supplement industry is that product adulteration does occur, and that these adulterants can trigger positives on drug tests. If you’re only a recreational climber, this probably doesn’t matter—but if you’re a competitor and could be drug screened, then I highly recommend choosing a creatine produced by a manufacturer that has a “Trusted by Sport” logo on their label. “Trusted by Sport” is a third-party service that randomly tests product batches to determine if they are pure, and while it is not a 100% guarantee, it is the closest you can get.

Another way you can have reasonable certainty that your product is unadulterated is to buy a name brand creatine (like Creapure®) from a bulk supplier such as TrueNutrition. Creapure® is a creatine monohydrate powder sold to other manufacturers for use in their products, and it’s highly unlikely the raw powder would come from the factory adulterated.

If you do use TrueNutrition.com, you can use the code BNRY639 to get a 5% discount off your entire order. Full disclosure, I get a small kickback if you use this code and are a new customer—but hey, you get something too. And just so you know I offer this in good faith, be sure to check their Promo page for any better deals, because you only get to choose one. Usually 5% off is the best deal, but sometimes it’s not!

Conclusion

If I had to choose a single supplement that every climber should take, it would be creatine. No other supplement has nearly the amount of research, or the track record, of improving athlete performance. Whether you boulder or sport climb, every climber can benefit from improved muscle creatine stores, especially in light of how incredibly important the creatine phosphate system is to climbers.2

Creatine will cause you gain a small amount of weight, but the gains you will make in strength, power, and power endurance vastly outweigh this small downside. Beyond a small increase in weight, there is no other reason to avoid creatine—most of the adverse effects associated with it are nothing more than rumors and myths that are completely unsubstantiated by science.

The bottom line is that creatine is safe, effective, and extremely cheap (at the time of writing, you can get a kilogram of Creapure® for about $22, and that kilogram will last around six months). It should be considered a “must take” for all climbers who are serious about improving their performance.

Want to learn more? Read Why Creatine Is So Important to Climbers and other great nutrition articles at ClimbingNutrition.com. Follow Climbing Nutrition on Facebook for the latest updates.

References

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