When looking specifically at human studies, there has been a failure of creatine supplementation to induce or exacerbate kidney damage in people with amyotrophic lateral sclerosis (ALS). Subjects do not experience kidney damage for up to or over a year’s worth of supplementation in the 5-10g range.[505][506][507] Postmenopausal women,[517] people with type II diabetes,[518] people on hemodialysis,[313] otherwise healthy elderly,[519] young people,[454][520][521] and athletes do not experience kidney damage either.[324] Moreover, numerous scientific reviews on both the long- and short-term safety of supplemental creatine have consistently found no adverse effects on kidney function in a wide range of doses.[522][523][524][452][525][451][526][527] However, while doses >10 g/day have been found not to impair kidney function, there are fewer long-term trials using such high chronic daily intakes.[527]
In regard to the blood brain barrier (BBB), which is a tightly woven mesh of non-fenestrated microcapillary endothelial cells (MCECs) that prevents passive diffusion of many water-soluble or large compounds into the brain, creatine can be taken into the brain via the SLC6A8 transporter.[192] In contrast, the creatine precursor (guanidinoacetate, or GAA) only appears to enter this transporter during creatine deficiency.[192] More creatine is taken up than effluxed, and more GAA is effluxed rather than taken up, suggesting that creatine utilization in the brain from blood-borne sources[192] is the major source of neural creatine.[193][192] However, “capable of passage” differs from “unregulated passage” and creatine appears to have tightly regulated entry into the brain in vivo[193]. After injecting rats with a large dose of creatine, creatine levels increased and plateaued at 70uM above baseline levels. These baseline levels are about 10mM, so this equates to an 0.7% increase when superloaded.[193] These kinetics may be a reason for the relative lack of neural effects of creatine supplementation in creatine sufficient populations.
Stronger muscles improve performance in a variety of sports. Sport-specific training routines are used by many competitors. These often specify that the speed of muscle contraction during weight training should be the same as that of the particular sport. Sport-specific training routines also often include variations to both free weight and machine movements that may not be common for traditional weightlifting.

In muscle cells, the creatine transporter is predominantly localized to the sarcolemmal membrane. Western blot analysis of creatine transporter expression revealed the presence of two distinc protein bands, migrating at 55kDa and 70kDa on reducing SDS-PAGE gels.[147][148] The 73kDa band has been reported to be the predominant band in humans, with no differences based on gender.[148] A more recent report demonstrated that the 55kDa creatine transporter variant is glycosylated, forming the 73 kDa protein. Therefore, the 55 and 75kDa protein bands are actually immature and mature/processed forms of the creatine transporter protein, respectively.[149]
Creatine is known to occur in highly concetrated levels in chicken photoreceptors, relative to other parts of the eye (10-15mM[466]) alongside high levels of creatine kinase.[466] The creatine transporter in human eyes also seems to be concentrated in the photoreceptors,[468] which are known to be susceptible to hypoxic cellular death[471][472] which, for humans, usually means retinal detachment.[473]
As a ingredient that has been tested time and time again and shown to positively affect the building of muscle, GAT has taken the highest-quality compound to create Essentials Creatine. Using HPLC-tested pharmaceutical grade creatine that's tested to be 99.9% pure, Essentials Creatine provides 5 grams in every serving which can increase muscle size, boost strength, and enhance muscle recovery. Keep Reading »
Beast Creature could be another good option for female athletes. It’s tasty, it contains five types of creatine, and it contains ingredients that could improve fat loss by increasing insulin sensitivity. One potential bonus is that it also has 70 percent of your daily biotin, a nutrient often included in women’s multivitamins due its purported benefits for hair and nails.
When it comes to finding the right meal plan, you have to start somewhere. Start with writing down what you eat in a food diary, calculate the calories you’re consuming daily (ex: 3,000 without protein shakes), and break those up into six meals (ex: 500 calories each), says Heath. Then, choose a macronutrient ratio. For example, the 40% protein, 40% carbs, 20% fat ratio is what Heath used to get bigger when he first started bodybuilding. “Buy a food scale, learn how to use it, and you may even have to learn to use the metric system, like grams instead of ounces,” Heath says. “You need to train your body to process food quickly, so eat every three hours.”
All you need to know about low creatinine levels Creatinine is a waste material in the body, and low levels can suggest a shortfall in liver function or activity. This MNT Knowledge Center feature looks at low creatinine levels., as well as information on what creatinine is, how it affects the body, and how to increase low creatinine levels. Read now
^ Spillane M, Schoch R, Cooke M, Harvey T, Greenwood M, Kreider R, Willoughby DS (February 2009). "The effects of creatine ethyl ester supplementation combined with heavy resistance training on body composition, muscle performance, and serum and muscle creatine levels". Journal of the International Society of Sports Nutrition. 6 (1): 6. doi:10.1186/1550-2783-6-6. PMC 2649889. PMID 19228401.
This is how the NPC differs from the NANBF. The NANBF takes a more direct approach by taking urine samples from all competitors that are tested for steroids and any other substances on the banned list. The NANBF also differs from the NPC when it comes to judging. The criteria for certain poses differs from organization to organization. The NANBF even has an elevated calf pose which is unique for their competitions.[citation needed]
Creatine ethyl ester increases muscle levels of creatine to a lesser degree than creatine monohydrate.[72] It may also result in higher serum creatinine levels[73] due to creatine ethyl ester being converted into creatinine via non-enzymatic means in an environment similar to the digestive tract.[74][75] At equal doses to creatine monohydrate, ethyl ester has failed to increase water weight after 28 days of administration (indicative of muscle deposition rates of creatine, which are seemingly absent with ethyl ester).[76] 

Before getting into the nitty-gritty details about supplements, it’s important to have a good understanding of how muscle growth works. When you take a muscle growth supplement, the role it plays in helping you reach your goals should be very clear. With the supplements available on the market, you can be sure that while some serve an important purpose, others are gimmicks. It’s easier to identify the money wasters if you know how muscle building works.


Creatine is stored in the body in the form of creatine and as creatine phosphate, otherwise known as phosphocreatine, which is the creatine molecule bound to a phosphate group.[39] Creatine phosphate is thought to maintain the ATP/ADP ratio by acting as a high-energy phosphate reservoir.[40] The more ATP a muscle has relative to ADP, the higher its contractility is, and thus its potential strength output in vivo.[41][42] This pro-energetic mechanism also affects nearly all body systems, not just skeletal muscle. [39] During periods of rest and anabolism, creatine can gain a phosphate group through the creatine-kinase enzyme pathway, up to a cellular concentration of 30uM[24] to be later used for quick ATP resupply, when needed.[43][44] 


Nitrate-rich foods like beets, radishes, and pomegranates are a great way to boost the production of nitric oxide (NO). Although there's very limited research examining the effects of beet root juice and pomegranate extract on resistance training, these ingredients have previously been shown to increase skeletal muscle blood flow and lead to reduced soreness, which may ultimately lead to improvements in strength and performance.[9,10]
That means it takes time for supplements aimed at joint treatment to work. So plan not to feel anything for about two months after you start using glucosamine. After that, pain control with the supplement is comparable to what happens with drug use, according to various studies. The typical doses are 1,200 milligrams daily of glucosamine and 800 of chondroitin, which can be doubled initially.
Creatine ingested through supplementation is transported into the cells exclusively by CreaT1. However, there is another creatine transporter Crea T2, which is primarily active and present in the testes [12]. Creatine uptake is regulated by various mechanisms, namely phosphorylation and glycosylation as well as extracellular and intracellular levels of creatine. Crea T1 has shown to be highly sensitive to the extracellular and intracellular levels being specifically activated when total creatine content inside the cell decreases [12]. It has also been observed that in addition to cytosolic creatine, the existence of a mitochondrial isoform of Crea T1 allows creatine to be transported into the mitochondria. Indicating another intra-mitochondrial pool of creatine, which seems to play an essential role in the phosphate-transport system from the mitochondria to the cytosol [13]. Myopathy patients have demonstrated reduced levels of total creatine and phosphocreatine as well as lower levels of CreaT1 protein, which is thought to be a major contributor to these decreased levels [14].
Over time, we naturally lose muscle mass in a process called sarcopenia. On average, men lose about 30% of their muscle mass during their lives. Usually, this begins in your 30s and progresses slowly as you age. But, don’t despair. You can rebuild and maintain muscle mass even as you age. Often, diet and exercise are enough. But, sometimes, if the above hormones play a role, your doctor may recommend medications and additional treatments (4).
As Heath talked in the office, Cremona presented him with steak and white rice. It was takeout, from Outback Steakhouse, because the two had just returned from a weeklong trip. Heath reached toward a bouquet of round plastic jars filled with powdered supplements. He scooped powder from one into a water bottle, shook it and drank. He compared himself to a racecar, always in need of fuel and delicate tinkering.
Trimethylglycine (TMG, betaine) is a dietary supplement and component of beet root, which is a methyl donor. It contributes to metabolic processes in the body which require a methyl group either directly (the methylation of homocysteine) or indirectly via replenishing the active form of folate or via replenishing S-adenosyl methionine (SAMe). As the synthesis of creatine (via GAMT) requires a donation from SAMe,[597] it is thought that TMG can aid in creatine synthesis, which has been noted in the rat liver in the absence of creatine supplementation.[598]
^ "The History of Weightlifting". USA Weightlifting. United States Olympic Committee. Archived from the original on 7 July 2013. Retrieved 3 September 2018. The genealogy of lifting traces back to the beginning of recorded history where man's fascination with physical prowess can be found among numerous ancient writings. A 5,000-year-old Chinese text tells of prospective soldiers having to pass lifting tests.
Español: aumentar la masa muscular, Deutsch: Muskeln aufbauen, Português: Aumentar a Musculatura, Nederlands: Spieren opbouwen, Français: se muscler le corps, Русский: нарастить мышечную массу, 中文: 增长肌肉, Čeština: Jak budovat svalovou hmotu, Bahasa Indonesia: Membangun Otot, Italiano: Sviluppare Massa Muscolare, 日本語: 筋肉をつける, हिन्दी: बॉडी बनायें (Kaise Body Banaye), العربية: بناء العضلات, 한국어: 근육을 키우는 법, Tiếng Việt: Tạo Cơ bắp, ไทย: สร้างกล้ามเนื้อ, Türkçe: Nasıl Kas Yapılır
At the time, low-potency creatine supplements were available in Britain, but creatine supplements designed for strength enhancement were not commercially available until 1993 when a company called Experimental and Applied Sciences (EAS) introduced the compound to the sports nutrition market under the name Phosphagen.[14] Research performed thereafter demonstrated that the consumption of high glycemic carbohydrates in conjunction with creatine increases creatine muscle stores.[15]
If you’re not lifting super-heavy weights, doing high-intensity workouts, or eating a mainly vegan or vegetarian diet, your body probably makes as much creatine as it needs. “Creatine is naturally found in animal-based products,” says Bates, “so your body can make plenty of creatine as long as you have a balanced diet that includes animal-based products.” Protein sources like beef, chicken, pork, and fish help your body produce the creatine it needs — it varies depending on the source, but, in general, a 3-ounce serving of meat will have about 0.4 grams (g) of creatine, Bates says. (6)
When you’re planning your high-protein meals, 20 grams of protein is the optimal amount generally accepted for muscle growth. Research has found that the body doesn’t use much more than 20 grams for muscle-building at any one sitting. Around 80 grams of protein per day (or, four meals containing 20-grams of protein each) is about right for most people.

Our bodies store creatine in our muscles so that we have quick access to it for fast, high-intensity movements, like sprinting or powerlifting, explains Autumn Bates, a certified clinical nutritionist and sports nutritionist in private practice in Manhattan Beach, California. “It's a nonessential amino acid, meaning your body creates it and you don't need to primarily get it from food.”
Lifters who follow high-volume or high-intensity resistance-training programs, as many bodybuilders do, may also benefit from carbohydrate intake immediately post-workout. Compared with a placebo, carbohydrates combined with protein immediately post-workout and one hour after a bout of resistance exercise have been shown to increase insulin levels and rates of glycogen resynthesis.[19]
In fact, in one new study comparing the effects of aerobic exercise versus resistance training on the psychological health of obese adolescents, researchers found that people in the resistance group experienced significantly greater self-esteem and perceived strength over four weeks. But what’s most interesting is that the feeling of getting stronger — rather than any measurable gains — was all it took to give them a boost.
Some of these medications that can harm the kidneys include cyclosporine (Neoral, Sandimmune); aminoglycosides including amikacin (Amikin), gentamicin (Garamycin, Gentak, others), and tobramycin (Nebcin, others); nonsteroidal anti-inflammatory drugs (NSAIDs) including ibuprofen (Advil, Motrin, Nuprin, others), indomethacin (Indocin), naproxen (Aleve, Anaprox, Naprelan, Naprosyn), piroxicam (Feldene); and numerous others.

Stash away your scale for several weeks — and set a strength training goal instead. That’s the advice of Lisette Cifaldi, director of behavioral health at Hilton Head Health weight loss resort who counsels patients. “I think strength training shifts your perspective,” she says. “The happiness doesn’t come from achieving a certain number [on the scale]. It comes from the process of getting stronger and feeling empowered that you’re navigating your own success.”

Though weight training can stimulate the cardiovascular system, many exercise physiologists, based on their observation of maximal oxygen uptake, argue that aerobics training is a better cardiovascular stimulus. Central catheter monitoring during resistance training reveals increased cardiac output, suggesting that strength training shows potential for cardiovascular exercise. However, a 2007 meta-analysis found that, though aerobic training is an effective therapy for heart failure patients, combined aerobic and strength training is ineffective; "the favorable antiremodeling role of aerobic exercise was not confirmed when this mode of exercise was combined with strength training".[36]
This amino acid is actually produced by your body and so is considered a non-essential amino acid. However, in addition to taking it in supplement form, beta-alanine is also found in protein-heavy foods like meat and fish (9). This amino acid has been linked to performance enhancement outcomes, especially for weightlifters. Studies show increased performance when taking this supplement.
In the early 2000s, the IFBB was attempting to make bodybuilding an Olympic sport. It obtained full IOC membership in 2000 and was attempting to get approved as a demonstration event at the Olympics, which would hopefully lead to it being added as a full contest. This did not happen and Olympic recognition for bodybuilding remains controversial since many argue that bodybuilding is not a sport.[11]
Unfortunately, it’s hard to significantly increase levels through food alone. That’s where supplementation comes in. For instance, in one 12-week study of resistance-trained individuals, taking HMB in tandem with a high-intensity lifting routine significantly improved muscle strength and size compared to lifting alone. Plus, in the off-chance that you push yourself too hard, HMB helps prevent the effects of overtraining—including muscle loss.
This is one of the best workouts for your hamstrings and glutes. Start in a standing position, feet shoulder-width apart. Hold the bar in front of you. Lower it to just below your knees. You can lower it further if you can keep a flat back and stable spine. Slowly return to the starting position. Keep the bar close to your body to protect your lower back.
Do Belgian squats (or "single leg squats") with a dumbbell. Hold out in front of your chest a dumbbell using both hands. Standing in front of a bench, lift your right leg back so that it's parallel to the floor and resting comfortably on the bench. Bend into a squat using the left leg, so that the right knee almost hits the floor. Lift and repeat 3 x 8. Repeat using opposite leg.
However, protein isn’t everything. Contrary to popular belief, carbohydrates and calories from fats are also important. To gain muscle, people who are slender or scrawny need to create a calorie surplus in order to bulk up. That means you need proteins and plenty of healthy carbs, vegetables and even some fats (think healthy fats like nuts, avocado, olive oil, etc.). Carbohydrates play a key role in building muscle. This macronutrient has gotten a bad rap for making people fat. However, if you work out properly, eating plenty of carbs is in your best interest. After training, it’s ideal to ingest some carbs in combination with protein to help replenish your muscles’ glycogen stores.
^ "Popular sports supplements contain meth-like compound". USA Today. October 25, 2013. Cohen said researchers informed the FDA in May about finding the new chemical compound in Craze. The team found the compound — N,alpha-diethylphenylethylamine — has a structure similar to methamphetamine, a powerful, highly addictive, illegal stimulant drug. They believe the new compound is likely less potent than methamphetamine but greater than ephedrine.

When creatine is increased in the fetus (from maternal supplementation of 5% creatine), the fetus has a greater chance of survival and increased growth rates to a level not significantly different than vaginal birth.[531] Protection from hypoxia has also been noted in the offspring’s diaphragm (through preserved muscle fiber size),[533] kidneys,[534] and neural tissue (due to less oxidation in the brain and less cellular apoptosis).[535]


^ Jump up to: a b c d e Wilson JM, Fitschen PJ, Campbell B, Wilson GJ, Zanchi N, Taylor L, Wilborn C, Kalman DS, Stout JR, Hoffman JR, Ziegenfuss TN, Lopez HL, Kreider RB, Smith-Ryan AE, Antonio J (February 2013). "International Society of Sports Nutrition Position Stand: beta-hydroxy-beta-methylbutyrate (HMB)". J. Int. Soc. Sports. Nutr. 10 (1): 6. doi:10.1186/1550-2783-10-6. PMC 3568064. PMID 23374455.
Creatine ingested through supplementation is transported into the cells exclusively by CreaT1. However, there is another creatine transporter Crea T2, which is primarily active and present in the testes [12]. Creatine uptake is regulated by various mechanisms, namely phosphorylation and glycosylation as well as extracellular and intracellular levels of creatine. Crea T1 has shown to be highly sensitive to the extracellular and intracellular levels being specifically activated when total creatine content inside the cell decreases [12]. It has also been observed that in addition to cytosolic creatine, the existence of a mitochondrial isoform of Crea T1 allows creatine to be transported into the mitochondria. Indicating another intra-mitochondrial pool of creatine, which seems to play an essential role in the phosphate-transport system from the mitochondria to the cytosol [13]. Myopathy patients have demonstrated reduced levels of total creatine and phosphocreatine as well as lower levels of CreaT1 protein, which is thought to be a major contributor to these decreased levels [14].
Creatine helps create essential adenosine triphosphate (ATP). This is the energy source of muscle contractions. By upping your levels, you can increase the amount of energy available to your muscles, boosting your performance. Because your muscle strength and size increases when you add weight and reps, improving your performance can be a game changer in terms of increasing your muscle mass. If you’re able to lift longer and harder, your muscles will grow. Creatine is certainly a winner among muscle building supplements.
If you are somebody that is tired of not getting results, wants to avoid trial-and-error, or you just want to be told exactly what to do to reach your goals, check out our popular 1-on-1 coaching program. You’ll work with our certified NF instructors who will get to know you better than you know yourself and program your workouts and nutrition strategy for you.
In addition to the proper amount of sleep, do not overdo your training regimen. While you might be tempted to think that "more is better," in fact the opposite is true. You can reach a point known as "over-training", in which you'll lose the ability to "pump" (engorge the muscles with oxygen-rich blood) your muscles, and this can even lead to muscle wasting—exactly the opposite of what you are trying to achieve. Here are some symptoms to be aware of if you think you may be falling into the over-training zone:
Creatine is not an essential nutrient[19] as it is naturally produced in the human body from the amino acids glycine and arginine, with an additional requirement for methionine to catalyze the transformation of guanidinoacetate to creatine. In the first step of the biosynthesis these two amino acids are combined by the enzyme arginine:glycine amidinotransferase (AGAT, EC:2.1.4.1) to form guanidinoacetate, which is then methylated by guanidinoacetate N-methyltransferase (GAMT, EC:2.1.1.2), using S-adenosyl methionine as the methyl donor. Creatine itself can be phosphorylated by creatine kinase to form phosphocreatine, which is used as an energy buffer in skeletal muscles and the brain.
The biggest mistake among young would-be bodybuilders is overdoing it, followed by not learning the proper techniques. Take those breaks and follow the correct form, or you'll give your body stress and injuries instead of muscle. Also make sure you're getting a large but balanced diet. Teens going through growth spurts need lots of food, especially when they're working out.
Creatine helps create essential adenosine triphosphate (ATP). This is the energy source of muscle contractions. By upping your levels, you can increase the amount of energy available to your muscles, boosting your performance. Because your muscle strength and size increases when you add weight and reps, improving your performance can be a game changer in terms of increasing your muscle mass. If you’re able to lift longer and harder, your muscles will grow. Creatine is certainly a winner among muscle building supplements.
Studies conducted in vegetarians tend to show cognitive enhancement in youth, possibly due to a creatine deficiency, as compared to omnivores.[272][60][61] Vegetarian diets have lower levels of circulating creatine prior to supplementation, but attain similar circulating levels as omnivores when both groups supplement.[272][273] Building on the latter, supplementation of creatine monohydrate in a loading protocol (20g daily in orange juice) in omnivores does not alter levels of creatine in white matter tissue in the brain (test subjects: competitive athletes).[274] In most of the parameters that vegetarians experience benefits, omnivores fail to experience statistically significant benefits[275], except possibly when sleep deprived, where the cognitive improvements rival that seen in vegetarians.[276] Elderly people who are omnivorous may also experience increases in cognition to a similar level, in regard to long-term memory as well as forward number and spatial recall, although the study in question failed to find any significant benefit on backward recall or random number generation,[38] the latter of which is a test for executive working memory.[277]
Try this little exercise some time: follow the supplement plan provided above for at least three months. Then quit all supplement use for a further three months and watch what happens. Sure, most supplement marketing involves hype and some companies make laughably outrageous claims, but there is no secret as to why the supplement industry is booming. Supplements work.
This claim has not been demonstrated at this time, and a recent comparative study of buffered creatine against basic creatine monohydrate found no significant differences between the two in 36 resistance trained individuals, in regard to the effects or the accumulation of creatine in muscle tissue.[71] There also were no significant differences in the amount of adverse side-effects reported.
Having a spotter nearby is particularly important when using free weights. Even someone in great shape sometimes just can't make that last rep. It's no big deal if you're doing biceps curls; all you'll have to do is drop the weight onto the floor. But if you're in the middle of a bench press — a chest exercise where you're lying on a bench and pushing a loaded barbell away from your chest — it's easy to get hurt if you drop the weight. A spotter can keep you from dropping the barbell onto your chest.
Another favorite bodybuilding supplement, creatine is an amino acid found in the body. The highest levels of this molecule are in your muscles and brain. It is made by your liver, pancreas and kidneys, but is also found in foods including meat, eggs and fish. Research has shown that it may help athletes including weightlifters who need short bursts of energy (5). In this study, creatine monohydrate proved to be an effective muscle builder. It works to improve body composition, muscle mass, strength and power.  Note that it was also more effective than other forms of creatine. How does it do this?

While they don’t play a big role, your body’s lean body mass and muscle strength is somewhat influenced by genetics. Actually, it’s good that they don’t have too much of an influence. Why? Because that means you have more of an influence on your muscle mass through your lifestyle. You can control it! If genetics were a determining factor, there wouldn’t be much you could do to change your situation.
Previous investigations have shown that a single dose of CM (8 grams) increased the number of repetitions performed during an upper-body resistance training protocol and reduced soreness at 24 and 48 hours post-exercise (compared to a placebo).7 Recently, researchers from Mississippi State University found that a single dose of CM (8 grams) significantly increased the number of lower-body repetitions compared to a placebo group.[8]

Cyclocreatine (1-carboxymethyl-2-iminoimidazolidine) is a synthetic analogue of creatine in a cyclic form. It serves as a substrate for the creatine kinase enzyme system, acting as a creatine mimetic. Cyclocreatine may compete with creatine in the CK enzyme system to transfer phosphate groups to ADP, as coincubation of both can reduce cyclocreatine’s anti-motility effects on some cancer cells.[96]

The basic principles of weight training are essentially identical to those of strength training, and involve a manipulation of the number of repetitions (reps), sets, tempo, exercise types, and weight moved to cause desired increases in strength, endurance, and size. The specific combinations of reps, sets, exercises, and weights depends on the aims of the individual performing the exercise.
This period also saw the rise of anabolic steroids in bodybuilding and many other sports. In bodybuilding lore, this is partly attributed to the rise of "mass monsters", beginning with Arnold Schwarzenegger, Sergio Oliva, and Lou Ferrigno in the late 1960s and early 1970s, and continuing through the 1980s with Lee Haney, the 1990s with Dorian Yates, Ronnie Coleman, and Markus Rühl, and up to the present day. Bodybuilders such as Greg Kovacs attained mass and size never seen previously but were not successful at the pro level. Others were renowned for their spectacular development of a particular body part, like Tom Platz or Paul Demayo for the leg muscles. At the time of shooting Pumping Iron, Schwarzenegger (while never admitting to steroid use until long after his retirement) said that "you have to do anything you can to get the advantage in competition".[citation needed] He would later say that he does not regret using anything.[8]
While they don’t play a big role, your body’s lean body mass and muscle strength is somewhat influenced by genetics. Actually, it’s good that they don’t have too much of an influence. Why? Because that means you have more of an influence on your muscle mass through your lifestyle. You can control it! If genetics were a determining factor, there wouldn’t be much you could do to change your situation.
Phosphocreatine is known to be a major source of energy for cardiac tissue alongside fatty acids, which are dominant under periods of normoxia (normal oxygen) while phosphocreatine becomes more important in periods of hypoxic stress.[281][282][283] The entire CK system plays a role in the recovery of the heart following ischemic/hypoxic stress, since blocking CK activity impairs recovery[284][285] and overexpressing CK activity promotes it.[286] This is due to the heart tissue needing high energy phosphate groups at this time, and the ischemic stress reduces CK activity and the ability of CK to donate these groups.[287][288]
In regard to practical interventions, concurrent glycogen loading has been noted to increase creatine stores by 37-46% regardless of whether the tissue was exercised prior to loading phase.[176] It is important to note, however, that creatine levels in response to the creatine loading protocol were compared in one glycogen-depleted leg to the contralateral control leg, which was not exercised.[176] This does not rule out a possible systemic exercise-driven increase in creatine uptake, and the increase in creatine noted above[176] was larger than typically seen with a loading protocol (usually in the 20-25% range). Consistent with an exercise-effect, others have reported that exercise itself increases creatine uptake into muscle, reporting 68% greater creatine uptake in an exercised limb, relative to 14% without exercise.[153]
×