Magnesium Glycinate vs Citrate: Which Form Is Best for Runners?

Walk down any supplement aisle and you will find magnesium glycinate, bisglycinate, citrate, oxide, malate and more. They are all magnesium, bound to a different partner molecule. That partner affects how well it is absorbed, how it sits in your stomach, and how much actual magnesium you get per capsule. This guide explains the differences in plain English and what matters for runners.

Why runners care about magnesium

Magnesium contributes to normal muscle function, electrolyte balance, the normal functioning of the nervous system and the reduction of tiredness and fatigue. UK adults need around 300mg a day for men and 270mg for women, and Food Standards Scotland notes that most people can get this from a varied diet rich in green vegetables, nuts, wholegrains, fish and dairy. A supplement is a top-up for when your diet falls short, not a replacement for it. For the bigger picture read magnesium for runners.

Magnesium glycinate and bisglycinate

Magnesium bound to the amino acid glycine. Bisglycinate is the same idea with two glycine molecules per magnesium, and the names are often used interchangeably. It is generally well absorbed and gentle on the stomach, which makes it a popular choice for daily use. Many people take it in the evening as part of a wind-down routine.

Magnesium citrate

Magnesium bound to citric acid. It is also well absorbed, but at higher doses it draws water into the gut and can have a laxative effect. That is fine for some people and very much not fine before a long run.

Magnesium oxide

Cheap and common in budget products. It contains a high percentage of magnesium by weight, but it is less well absorbed than glycinate or citrate and is more likely to upset your stomach.

Malate, threonate and the rest

Other forms are marketed for specific benefits. The evidence for those specific benefits is limited, and none of them carry extra authorised claims. For most runners they are not worth paying a premium for.

How to read a magnesium label

This is where most people get caught out. A label might say “400mg magnesium glycinate”. That is the weight of the whole compound, magnesium plus glycine. The amount of actual (elemental) magnesium is a fraction of that. Good labels show both, or show the elemental amount with its percentage of the Nutrient Reference Value (NRV). Always compare elemental magnesium, not compound weight.

More is not better. The NHS advises that taking 400mg or less a day of magnesium from supplements is unlikely to cause harm, and high doses in the short term can cause diarrhoea.

So which is best for runners?

• For daily use: glycinate or bisglycinate. Well absorbed, easy on the stomach, and easy to fit into an evening routine.
• If you are prone to constipation: citrate may suit you, but not before training.
• Avoid: cheap oxide if you have a sensitive stomach, and products that hide the elemental dose.

Runner Sleep & Recovery uses 400mg magnesium bisglycinate with 15mg zinc, which contributes to the normal function of the immune system. It is designed as an evening routine, with no stimulants, and is Cologne List® tested. It is also part of the Marathon Race Ready Bundle and the Beginner Runner Starter Pack.

Magnesium and sleep

Magnesium is widely taken at night, and a good evening routine helps most runners sleep better. But there is no authorised claim linking magnesium to sleep, and we do not make one. What helps sleep most is consistent timing, a dark cool room and not doing hard sessions late. More in how to sleep better after a hard run.

FAQs

Is magnesium glycinate the same as bisglycinate?

Essentially yes. Bisglycinate specifies two glycine molecules per magnesium; the terms are often used interchangeably.

When should runners take magnesium?

Evening suits most people, as part of a wind-down routine. Consistency matters more than timing.

Do runners lose a lot of magnesium in sweat?

Some, but the amounts are small compared with sodium. Diet remains the main factor.

Food supplements should not be used as a substitute for a varied, balanced diet and healthy lifestyle. Speak to your GP if you have kidney problems or take medication.