Newsletter #322: Magnesium & Muscle Soreness đȘđŒ
This Weekâs Research Highlight
đ Magnesium supplementation reduces muscle soreness and enhances recovery from exercise.
Early research has shown that the stress of exercise leads to perturbations in magnesium status within the body. Muscle cell contraction depends upon intracellular magnesium, and strenuous activity elicits accelerated magnesium loss through sweat and urine.
Unsurprisingly, due to a combination of greater magnesium demand and rising magnesium losses, athletes show a sustained decrease in plasma magnesium. What toll might this have on training and recovery? And can supplementation with magnesium improve the situation?
To examine how magnesium affects exercise performance and recovery, Italian researchers conducted a systematic review of human trials published within the last two decades.
Their screening process produced four eligible studies, enrolling a total of 73 participants:
- One study measured the effects of Mg on muscle soreness and performance in the bench press
- One study looked at how seven days of Mg supplementation affected muscle soreness following a 10 kilometer run
- One trial examined how Mg supplementation influenced markers of muscle damage parameters in elite basketball players
- One study tested how daily magnesium supplementation over three weeks affected muscle damage in professional cyclists competing in a stage race
Overall, the studies found that magnesium supplementation led to improved performance, better recovery, reduced muscle soreness, and protection against muscle damage.
The underlying mechanisms that drive these improvements are not entirely clear, but the researchers speculate that it may be related to the essential role of magnesium in muscle contraction. Muscle cells contain a structure known as the sarcoplasmic reticulum, which is basically a calcium reservoir for your muscles. The main job of the sarcoplasmic reticulum is to store and control the activity of calcium ions.
This calcium transport system is what regulates muscle contraction. Contraction of muscle cells depends upon the release of these calcium ions, and magnesium ions are required to help orchestrate this process. Consequently, they suggest that low levels of magnesium might inhibit the release of calcium via the sarcoplasmic reticulum, which could in turn contribute to fatigue and muscle soreness.
Rather than dig into the details of the individual trials, letâs go over the practical takeaways from the paper.
What is the best form of magnesium for fighting recovery and soreness?
These studies used a variety of different forms of magnesium, including glycinate, oxide, and lactate, so it's sort of hard to draw meaningful conclusions from the trials included in this review.
However, a comparison of the absorption profile of various magnesium compounds found that magnesium citrate was the most efficient form for boosting muscle magnesium specifically.
How much magnesium do you need to take?
Based on the aforementioned increase in magnesium demand, the researchers estimate that physically active individuals need to increase their daily Mg intake by around 10-20%, compared to sedentary counterparts.
Currently, the recommended daily intake of magnesium is 420 mg for men, and 315 mg for women. Thus, physically active men and women should shoot for a daily intake of at least 510 and 380 mg respectively. The doses of Mg used in the studies included in this analysis (ranging from 350-500 mg) would easily cover that hypothetical requirement, especially in the context of a healthy diet.
Notably, magnesium citrate was previously shown to be most effective at enhancing muscle magnesium at a dose of at least 400 mg*, which lines up with the amounts administered in these studies.
When should magnesium be taken for this indication?
These trials were not super consistent with respect to the timing of magnesium administration.
Human pharmacokinetic studies suggest that magnesium absorption starts at around 1 hour after consumption, and reaches a peak at the 2 hour mark, declining at 4-5 hours after intake.
Consequently, it probably makes sense to take the supplement around 2 hours before the exercise bout, since the training window will overlap with peak levels of magnesium.
*If you are going to experiment with this yourself, I would strongly advise starting at a lower dose and working up gradually because magnesium citrate can be hard on your gut. You may find that you need to use a mix of citrate and another gentler form, like glycinate.
Random Trivia & Weird News
Magnesium is named for a region in Greece.
The element magnesium was first isolated in pure form by British chemist Humphry Davy in 1808.
However, the mineral was discovered many centuries earlier (in the form of talc, or magnesium silicate) in the Magnesia district of Thessaly.
Ancient Greeks and Romans used it for medicinal purposes, and in retrospect they may have been onto something with that application â although I wouldnât recommend ingesting talc.
Podcasts We Loved This Week
- Marta Garaulet: Melatonin, meal timing and chrononutrition. Via Sigma Nutrition Radio.
- Michael Papadakis: Can we really âoutrun the Grim Reaper?â Via In Conversation.
Products We Like
NOW Magnesium Citrate
Magnesium citrate has the advantage of being well-absorbed by the body (and especially skeletal muscle, apparently). It is also pretty easy to find, compared to some of the more obscure magnesium compounds out there. I like this supplement in particular because it has been lab-tested by the friendly folks at ConsumerLab, so you can trust that it contains what the label claims.
humanOS Catalog Feature of the Week
How Much Physical Activity Do We Need?
In this course, we:
- Examine how physical activity is defined and measured
- Explore the physical activity of our ancient ancestors and modern day hunter-gatherers, to get a sense for ânaturalâ patterns of physical activity for which we evolved
- Look at how physical activity and fitness affect health and lifespan
- Review the key components of a smart activity program, so you can get the right dose of physical activity for you!
Wishing you the best,
