While it is usually touted for its benefits for a good night's sleep, this little nutrient is more versatile than you might think.

Written by: Tom Ward
Written on: June 30, 2026
If you’ve ever worked with a personal trainer, one of the first things they likely recommended was a magnesium supplement. Touted as a way to support muscle function and recovery, magnesium is gaining a bit of a reputation as a performance essential. It makes sense. Magnesium is involved in over 300 enzymatic reactions in the body — including muscle contraction and nerve signalling — making it a foundational bit of nutritional infrastructure for physical performance. Taken long-term, it should, in theory, support a more functional, recovered body.
While all of this sounds great, magnesium rarely gets the same attention as creatine or caffeine when talking about fitness supplements, and the actual science behind magnesium’s efficacy is still in the early stages.
This leaves us with one major question: is magnesium really a performance booster — and how much can it actually help us achieve our recovery goals?
Magnesium is called an “essential mineral” because it’s used throughout the body, impacting everything from bone health to brain function. From a sporting perspective, magnesium is also important for energy production, muscle function, and nerve signalling.
“It’s vital for the processes that help cells produce and use Adenosine Triphosphate (ATP), which is often described as the body’s main energy currency,” explains Dr. Amir Bhogal, superintendent lead pharmacist and director of Pyramid Pharmacy Group.
In simple terms, ATP is what cells use to power a lot of basic body functions, including helping our muscles contract and relax during exercise. “If our magnesium levels are low, movement may become less efficient, we may experience cramping, and we may feel fatigued,” says Dr. Bhogal.
As sports science is discovering, one of the most important parts of performance is actually how well we recover. It’s during down time (like sleep) when our bodies repair themselves, and when the building blocks of our gym work come together. “Magnesium is a great supplement for post-workout,” explains Dr. Roxana Ehsani, a board-certified sports dietitian who works with sports teams in the US. “When athletes are sore post-workout or complain of trouble sleeping or muscle cramps, I recommend magnesium supplements before bed,” she says, citing magnesium’s ability to relax muscles.
It isn’t a cure-all, though. Dr. Bhogal says that “taking a magnesium supplement will not automatically make every person stronger or more energetic.” While magnesium is often discussed alongside performance supplements, it doesn’t technically work in the same way. “It is important to understand that magnesium is a nutrient, not a stimulant,” Dr. Bhogal adds. While creatine might give you an instant boost, magnesium is about supporting your body’s systems long-term.
We know, anecdotally at least, that magnesium seems to have a significant impact on both our performance and recovery. But what does the research actually say?
A 2019 systematic review did find some promising evidence that magnesium supplementation may improve muscle strength and reduce inflammation. But there’s a caveat: the same review found little consistent effect on endurance performance, and only two of the 22 studies researchers reviewed were rated as 'high quality' studies. “In practical terms, this means there is a scientific reason to be interested in magnesium, but the evidence is not strong enough to say it reliably improves performance for everyone,” says Dr. Bhogal.
So far, the evidence suggests that magnesium may be more useful for maintaining normal performance than for creating a dramatic performance gain. A 2025 study in the journal Nutrients backs this. Analysing short-term magnesium use in people who already had sufficient levels of the nutrient, researchers found that too much magnesium might actually hinder performance, with the possibility of a decrease in cardio ability.
“Magnesium may support strength and recovery in some people, but it should not be marketed as a guaranteed endurance booster or a universal training aid,” says Dr. Bhogal. Again, magnesium is a nutrient, so the key is to incorporate it as a regular part of our diets. The problem is, that few of us are actually managing to do so.
Magnesium deficiency is quite common, but most people aren't aware of it. “What people don’t realise is that we lose magnesium in sweat,” says Ehsani. A 2023 systematic review in the journal Food and Nutrition Research found that athletes likely need to take in more magnesium than the average person, largely due to the effects of dehydration. In other words, if you’re exercising, it's important to stay hydrated with a good balance of isotopes and electrolytes.
The good news is that we can also get magnesium from our food, although Dr. Bhogal says that those who skip foods like whole grains, nuts, seeds, pulses and leafy green vegetables can quickly find themselves magnesium-deficient. Again, it’s about being conscious of what you’re putting into your body and aiming for dietary diversity. Only after that should supplements come into play.
Finally, certain health conditions and medicines can also affect magnesium levels. People with gut conditions that reduce absorption, poorly controlled diabetes, or who drink a lot of alcohol may be more vulnerable. If you are considering magnesium supplements and suffer from any of the above, it’s worth speaking with your GP first.
Ehsani is a fan, adding that she considers magnesium “essential to health, and not overhyped at all.”
Dr. Bhogal agrees, but reiterates that magnesium has the largest impact on performance when levels are low. “If someone is falling short, the body may have less support for muscle control and recovery after physical effort,” he says, adding that “magnesium is not the first answer to poor performance, but it is one of the basic factors worth checking when slower muscle recovery or reduced physical capacity are difficult to explain.”
This article is for informational purposes only, even if and regardless of whether it features the advice of physicians and medical practitioners. This article is not, nor is it intended to be, a substitute for professional medical advice, diagnosis, or treatment and should never be relied upon for specific medical advice. The views expressed in this article are the views of the expert and do not necessarily represent the views of Healf
Tom Ward is a former Men's Health features editor, and writes regularly on sports, fitness and adventure for the Red Bulletin, Outside, and the Sunday Times. He is the author of the novels The Lion and The Unicorn, and TIN CAT.