Creatine, since its discovery in 1832, is one of the most studied supplements. The vast majority of studies and articles propose creatine from an ergogenic perspective (a substance that tends to increase work output); in fact, this is its main use and the main reason why this supplement is marketed. In a future article, I will discuss its use in sports performance.

Momentary family issues made me want to investigate the use of creatine in the loss of muscle tissue due to age -sarcopenia- or accidental injury. That is to say, this article is about:

Creatine to recover atrophied muscle due to injury or muscle loss due to age.

For those who have only heard the word ‘creatine’ and don’t know what it is:

Creatine is a nitrogenous organic acid synthesized from different amino acids, hence its structural similarity. In living beings, it is found in muscle and nerve cells. Its discovery is credited to a French chemist named Crevreul in 1832 who discovered the component in skeletal muscle, and identified it as Kreas, a word that means “meat” in Greek.

Creatine is an anabolic (Oops! How afraid of misinterpreting that word) mostly used as a dietary supplement, especially in sports that require strength and power, since its ergogenic effect makes it possible to work with greater loads, higher repetitions or short rest periods.

It is not an essential nutrient since it is biosynthesized through different amino acids -arginine, glycine and methionine- mainly in the liver and kidneys to be transported by the blood to the muscles. However, its exogenous consumption comes from the intake of meat or supplements. This is why carnivores tend to show higher levels, which can be matched by incorporating a supplement into the diet of those who do not consume meat.

Although it was a long discussion, creatine is not among the prohibited or doping substances mentioned by the International Olympic Committee. In fact, within the Australian Institute of Sport – and other international entities – it is one of the type A supplements, which have a good number of validated scientific studies.

What is the function of creatine in the body?

Carbohydrates provide quick energy in an anaerobic environment (energy without the need for oxygen), something that occurs during high-intensity exercise, while fats provide sustained energy during periods with available oxygen (low exercise intensity and rest). The breakdown of carbohydrates, fats, and ketones produces ATP (this doesn’t refer to the Professional Tennis Association, but to Adenosine Tri-Phosphate). When cells use ATP for energy, this molecule is converted into ADP (adenosine di-phosphate) and then into AMP (adenosine mono-phosphate). For those who don’t see it yet, the molecule went from tri(3) to di(2) to mono(1), that is, it was giving up a phosphate so you can continue doing high-intensity physical activity. In the cell, creatine performs the function of donating a phosphate group (energy again) to ADP, returning this molecule back to ATP.

For those who still don’t see it, think of ATP as the currency for energy exchange in our body. The extraction of this energy is given by hydrolysis (breaking of the molecule when due to the introduction of a water molecule) going from having 3 phosphagen groups to having 2. (References: 1, 2 , 3).

Increasing the availability to cellular level of this substrate by exogenous intake (at this point it is actually called phosphocreatine, but let’s not get tangled up in semantics, –phosphocreatine pool-) this passage of ADP to ATP can be re-cycled more quickly.

ATP stores are rapidly depleted during intense muscular effort (running fast, jumping) one of the greatest benefits of creatine supplementation is the ability and continuity to regenerate ATP stores quickly, which can promote strength increases (yes, give you more power) and it is because of this advertising that creatine supplements sell so much.

Of course, as always, everything has a limit and you cannot continue gaining superpowers no matter how much you continue increasing the dose. More than 95% of creatine is found in the muscles, so the deposits of this substance are related to them, they can increase up to a certain limit (like muscles) and of course, it can decrease a lot when losing muscle mass (ref). Since the most important thing is to know what is most important, it should be clarified that what we are looking for is to recover or increase muscle mass, not to have more nutrient going around and not to use it for a specific purpose.

Creatine is an energy substrate that, together with others, is responsible for providing ATP, the main monetary exchange of energy. This is a small peptide that serves as a reservoir for high-energy phosphate groups. An increase in creatine intake (through food or supplements) increases cellular energy stores, promoting short-term ATP regeneration. However, there’s a limit to the savings account—which is actually quite low—so when you need to refuel your body for longer periods than a sprint or a couple of jumps, glucose or fatty acids are responsible for continuing to provide fuel.

What forms does creatine come in?

Meats (uncooked) with creatine content: Ref 1, 2.

• Beef steak, (minimum connective tissue): 4.8g each kg
• Poultry meat: 3.4 g/kg
• Rabbit: 3.4 g/kg
• Liver:0.2 g/kg
• Kidney: 0.23 g/kg
• Lung: 0.19 g/kg

“Creatine Monohydrate” This is the most common form in which it is offered as a supplement. In fact, unless specified, all studies use this type of exogenous creatine. It is presented in powder or capsule form. They always come with 5-gram scoops.

Sarcopenia or age-related muscle loss.

Sarcopenia is defined as the age-related loss of muscle mass. As a consequence of decreased muscle mass, strength, metabolic rate, and functionality (less movement) are lost, resulting in a significant loss of quality of life. Like any healthcare profession, the goal is to increase not only life expectancy but also its quality. Therefore, muscle and movement loss counteract health, resulting in increased hospitalizations, treatment, rehabilitation, and various other aspects. more than will correspond to the situation of each family or person, and being less personal, public health expenses.

It has been proven that resistance training improves muscle mass and strength. However, some studies show that the loss of muscle mass in older adults continues to manifest itself even if they have continued resistance training for most of their lives, suggesting that there are other factors such as nutrition that may affect the biological age of the muscle. (ref 1, 2)

Whenever I talk about strength training or resistance training, the first thing that comes to mind for many people is having to lift a barbell with at least 100 kilos. However, strength is relative to several things, including the amount of muscle mass one has. Therefore, we must stop looking at someone else’s bodyand ask yourself how you can improve your strength. For me it will be squatting 150 kilos (it’s actually 100), for my mother it may be sitting down and getting up from the chair with one leg, for my grandmother it may be getting up without the help of her hands, but all of us – my mother, my grandmother, and I – can and should improve our strength for the reasons explained above. How much or how is it for you? 

How can creatine consumption benefit older adults?

Creatine supplementation, whether through meat consumption or other sources, and strength training, has been shown to have a beneficial effect on biological muscle age. (ref 1, 2)

Although it is a field that is under continuous study and so far no long-term adverse effects of the different sources of creatine have been found, unfortunately it is not known precisely which could be the best strategies in advanced ages.

Everything indicates, including this meta-analysis, thatcreatine consumption alongside strength training reduces cachexia, bone mass loss – making us more fragile – and the symptoms of wear and tear caused by some diseases such as cancer, more than training alone. Consumption even seems to contribute to bone mineral density and, of course, the biological age of the bone. Nothing is magic, or at least nothing is magic on its own. Without training, all we do is have one more substrate going around without generating what we really want to generate.

The results of this other meta-analysis are encouraging in supporting creatine supplementation during counter-resistance training, in healthy aging by increasing muscle mass and strength gains and functional performance over when training is performed alone; however, the limited number of studies indicates that more work is needed.

Logic would also indicate that creatine consumption could prevent sarcopenia, but, and there is always a but, there is a study done in mice that has not found a significant preventive effect (of course, and like everything, further studies are needed).

Other important tools.

It is important to remember that high creatine consumption, whether through supplementation or food, is just another tool that, as already explained, is useless if you are not exercising. In addition, creatine can be an added bonus for building muscle mass, but if we neglect our diet, our protein intake is low, and our energy and dietary quality are low, no amount of creatine can help.

Therefore, a very good – and free – position paper is the one from JAMDA (Journal of the American Medical Directors Association) where the PROT-AGE group recommends

“PROT-AGE Recommendations for Protein Levels in Geriatric Patients with Acute or Chronic Illnesses.
• The amount of additional dietary protein or supplemental protein needed depends on the disease, its severity, the patient’s nutritional status before the illness, as well as the impact of the illness on the patient’s nutritional status.
• Most older adults who have an acute or chronic illness need more dietary protein (i.e., 1.2-1.5 g/kg body weight/day); people with severe illness or injury or with marked malnutrition may need up to 2.0 g/kg body weight/d.
• Older people with severe kidney disease (i.e., estimated glomerular filtration rate [GFR] <30 ml/min/1.73 m2) who are not on dialysis are an exception to the high-protein rule; these people need to limit their protein intake.

This is a fairly extensive article, with a lot of evidence-based information to take into account regarding different diseases, management of other supplements, protein consumption, etc. For those who want it this is the link. And for those who don’t speak English, translating it with Google is an important help.

Creatine for injuries.

Anyone who has had surgery on a limb (in my case, my left leg and arm) will have realized that after a few weeks of immobility, muscle loss is very noticeable; one leg remains muscular while the other transforms into a spaghetti with each passing day.

In this study, they investigated healthy adults who had to immobilize one leg for two weeks while taking 20g of creatine daily and then consuming 5g while doing an 8-week rehabilitation. It was observed that the creatine group failed to reduce atrophy during immobilization (for those who understand a little more, a 10% reduction in cross-sectional area and a 22-25% reduction in force production), however, they did experience a significantly improved rate of power recovery.

Creatine supplementation did not reduce muscle loss during immobilization, but it appears to improve muscle rehabilitation afterward.

In contrast, this other studyconducted in elderly individuals undergoing knee replacement surgery, 10 g of creatine for ten days prior to surgery and 5 g every day afterward did not modify tissue loss or any of the muscle metabolites, when compared with placebo.

Side effects, fear of consumption and other weeds.

So far, there are no clinically significant side effects from acute creatine supplementation. Numerous human trials have been conducted where only gastrointestinal disorders were found as adverse effects (in cases of excessive consumption at one time, as with everything) and there have been cases of cramps attributed to insufficient hydration. This is at least supported by this study. On the other hand, this paper concludes that:

We investigated hepatic changes during medium-term (4 weeks) creatine supplementation in young athletes. None showed any evidence of dysfunction based on serum enzymes and urea production. Short-term (5 days), medium-term (9 weeks), and long-term (up to 5 years) oral creatine supplementation have been studied in small cohorts of athletes whose renal function was monitored by urinary protein excretion rate and clearance methods. No adverse effects on kidney function were found. This review does not aim to draw conclusions about the effect of creatine supplementation on athletic performance, but we believe there is no evidence of harmful effects in healthy individuals.

There is strong evidence to support the absence of adverse side effects at a dose of 5 g per day, as well as evidence of a dose of 10 g per day for 310 days studied in older adults aged 57 +/- 11.1 years.

Kidney clarification:

Creatine is normally metabolized to creatinine (there is an ‘ine’ difference at the end of the word), which is normally eliminated by the kidneys. When the kidneys fail and can’t clean the blood as efficiently, certain metabolites remain in the blood and cannot be cleaned properly. Creatinine is easy to measure and is a biomarker of kidney damage—that is, elevated creatinine indicates that the kidneys are not functioning properly. Low doses of creatine do not cause alterations in this biomarker in normal adults, but high doses of creatine supplements can cause a false positive (an increase in creatinine, due to creatine being converted to creatinine, which does not indicate kidney damage) and are a diagnostic error. (estudy, study)

Important note from the author.

I am not, was not, and will not be a supplement seller (and I promise not to delete this in the future). This compilation, study, and bibliography search, as I mentioned above, was done for personal reasons. I hope you take it as an informative guide and decide (together with your doctor, family, and of course, your nutritionist) whether or not to increase your creatine intake. It would really be an honor if you shared it if you agree, but do not use it in a marketing way to sell a product.

Reference bibliography: