It’s a popular supplement among gym-goers and athletes, but what is creatine? If you’re considering adding it to your routine, it’s important to understand a few key points: is it safe and effective? And, if you’re following a plant-based diet, is creatine vegan? We look at the evidence.April 28, 2022 5:18 pm September 13, 2021 9:17 am
What is creatine?
Creatine is an organic compound (officially speaking, it’s a nitrogenous amine).(1) We make it in our own bodies.
The liver and kidneys are mainly responsible for making creatine, although the pancreas contributes to a lesser extent. However, most of the body’s stores of creatine (about 95%) are in the skeletal muscles. The remaining 5% goes to the brain, liver, kidneys and (in men) the testes.(2)
We make about a gram of creatine per day. But we also get it from our diet. Humans predominantly get their dietary creatine from meat, and vegetarians tend to have lower levels of it.(2) Thus, it may be of particular interest to vegetarians and vegans as a supplement, assuming that their supplemental creatine is vegan. (More on that below!).
Why are people interested in creatine as a supplement?
Interest in creatine boomed in the 1990s, when athletes and gym-goers started taking it as a supplement to boost their workouts. It is most closely linked with resistance training.
It became incredibly popular. In one 1999 study, 48% of male athletes said they were taking or had previously taken a creatine supplement.(1)
Studies have shown that creatine supplementation helps improve performance with short, high intensity sports such as strength training, weightlifting and cycling.(1)
While it is still a very popular supplement, it has been somewhat displaced by whey protein. More recent surveys of American high school students found that this type of protein powder has been more popular than creatine in recent years.(2)
How does creatine work?
The reason creatine is so useful in exercise comes down to how you create and use energy in your muscles.
Strap in for some heavy science – it’s important, we promise!(1)
As we know, creatine is made in your liver and kidneys and is then transported to your muscles, where it hangs out until needed.
When your muscle cell requires energy (for example, if you’re exercising), it makes use of a compound called ATP. This stands for adenosine 5-triphosphate. It’s a complex molecule which we won’t get into now, but suffice to say that it has a phosphate group stuck onto it.
During a process called hydrolysis, one of ATP’s phosphate groups breaks off, releasing energy. Great! Now your cell can use that energy for its processes. The ATP, minus one phosphate group, becomes ADP (adenosine diphosphate).
So where does creatine come in? Well, as you may have guessed, it’s all to do with phosphorus.
Once inside your cells, creatine is the willing recipient of the phosphate lost by ATP. It has been ‘phosphorylated’ (had a phosphoryl group stuck onto it) to make a different compound called phosphocreatine.
But the great thing about creatine is that it can hand its phosphate back to ADP to make more ATP. This process is called the ‘phosphocreatine shuffle’.
That means more energy for your cell to use, and is the reason why it’s thought to improve performance in exercise.
Does creatine work for all types of exercise?
Creatine is mostly associated with short, sharp bursts of exercise, as mentioned above. This is because your body soon moves on to other methods of providing your cells with energy.
If you jump straight into some strenuous exercise, your cells only have a small reserve of ATP which they can draw on for energy.
When that runs out, they can make use of the phosphocreatine shuffle to produce more ATP and carry on doing the same thing.
However, nothing lasts forever. The phosphocreatine shuffle is only your cell’s main way of producing energy for about the first ten seconds of intense exercise.
After that your cells move onto a process called anaerobic gycolysis. This is when your body converts glucose (sugar from your food) into lactate, providing more of that precious ATP. This phase lasts from about 10 seconds to two minutes of maximum effort.(2)
After that, you’ll move on to aerobic respiration. This is the type your cells will be using if you head out for a 5K run or go swimming for half an hour. It happens when glucose and oxygen react to produce CO2 and water.
So, how does creatine help you? Well, having more reserves of creatine in your muscles means that the phosphocreatine shuttle stage can last longer. While it’s less important for longer types of exercise, if you do short sharp bursts (such as lifting a heavy weight), it could theoretically improve your performance.
What’s the evidence that creatine works?
The good news is: there’s quite a bit of evidence for creatine helping with certain types of exercise.
For instance, one study looked at 19 healthy men who did resistance training, dividing them into two groups. The first took creatine, the second took a placebo.
They then all followed a 12 week regimen of heavy resistance training. Those who took creatine built more muscle and were able to bench press more at the end of the training period.(3)
Scientists think that this is because those who took creatine were able to rapidly regenerate ATP in their cells in the breaks between resistance sets. That meant they were able to work out at a higher intensity throughout the training programme.(1)
Meanwhile a review undertaken by the International Society of Sports Nutrition found that 70% of the studies they reviewed reported improved exercise performance with creatine. Furthermore, the average improvement in performance ranged from 10-15%.(4)
There’s also evidence that creatine can help with other types of short bursts of exercise, such as swimming or running sprints.(4)