What is magnesium and why does it matter?
Pure magnesium is the second most abundant mineral in cells after potassium. It is required for more than 300 biological reactions in the body, including those involved in the synthesis of fat, protein, and nucleic acids, neurological activity, muscular contraction and relaxation, cardiac activity and bone metabolism. Even more important for hockey players is magnesium’s pivotal role in both anaerobic and aerobic energy production,
What foods contain good amounts of magnesium?
The following foods can be considered; Pumpkin seeds (roasted), Almonds, Brazil nuts, Sesame seeds, Peanuts (roasted, salted), Walnuts, Rice (whole grain brown), Wholemeal bread, Spinach, Cooked beans, Broccoli, Banana.
Optimising dietary magnesium intake
The UK recommended intake for magnesium is set at 300mg for men and 270mg for women (6). The US has recently revised its figures upwards and now recommends an intake of 400mg per day for men aged 19-30 and 420 for those over 30; the figures for women under and over 30 are 300 and 310mg per day respectively (7). However, some investigators believe that even these levels are too conservative and that they should be set even higher at 450-500mg/day for all adults (8).
Different Types of Magnesium Supplements
If for whatever reason you decide you need a supplement, be aware that there are a wide variety of magnesium supplements on the market, which includes Magnesium glycinate, Magnesium carbonate, and Magnesium citrate. Courtesy of the fact that magnesium must be bound to another substance. There’s simply no such thing as a 100% magnesium supplement. The substance used in any given supplement combination can affect the absorption and bioavailability of the magnesium, and may provide slightly different, or targeted, health benefits:
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Magnesium glycinate is a chelated form of magnesium that tends to provide the highest levels of absorption and bioavailability and is typically considered ideal for those who are trying to correct a deficiency |
Magnesium oxide is a non-chelated type of magnesium, bound to an organic acid or a fatty acid. Contains 60 percent magnesium, and has stool softening properties |
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Magnesium chloride / Magnesium lactate contain only 12 percent magnesium, but has better absorption than others, such as magnesium oxide, which contains five times more magnesium |
Magnesium sulfate / Magnesium hydroxide (milk of magnesia) are typically used as a laxative. Be aware that it’s easy to overdose on these, so ONLY take as directed |
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Magnesium carbonate, which has antacid properties, contains 45 percent magnesium |
Magnesium taurate contains a combination of magnesium and taurine, an amino acid. Together, they tend to provide a calming effect on your body and mind |
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Magnesium citrate is magnesium with citric acid, which has laxative properties |
Magnesium threonate is a newer, emerging type of magnesium supplement that appears promising, primarily due to its superior ability to penetrate the mitochondrial membrane, and may be the best magnesium supplement on the market |
As a result, after consulting with your medical practitioner, you might consider taking magnesium supplements to boost magnesium requirements particularly if you are training hard and playing alot. It does have not only health benefits but specific performance benefits worth considering. See below information
Magnesium – is it more important for hockey players than we thought?
Most sportsmen and women know that magnesium is required for health, but few really appreciate its importance for sport performance. Think of the ‘big hitters’ in minerals for sports nutrition and the chances are you’ll come up with iron, calcium and perhaps zinc. Yet despite magnesium’s pivotal role in energy production, many coaches and players remain unaware of its critical importance in maintaining health and performance. To make matters worse, magnesium is a mineral that is often poorly supplied in the diet; dietary intakes of magnesium in the West have declined to less than a half of those recorded at the end of the 19th century and are still falling (1).
Moreover, many nutritionists believe that the amount of magnesium required for optimum health has been underestimated in the past, and research suggests that even small shortfalls in magnesium intake can seriously impair performance. This evidence includes the following;
A study on women put on a magnesium restricted diet, which showed for a given cycling workload, peak oxygen uptake, total and cumulative net oxygen utilisation and heart rate all increased significantly during the period of magnesium restriction, with the amount of the increase directly correlated with the extent of magnesium depletion (i.e. the magnesium deficiency reduced metabolic efficiency, increasing the oxygen consumption and heart rate required to perform a given workload)(2);
- A study of male athletes supplemented with 390mg of magnesium per day for 25 days, which resulted in an increased peak oxygen uptake and total work output during work capacity tests(3);
- A sub-maximal work study, which showed that magnesium supplementation reduced heart rate, ventilation rate, oxygen uptake and carbon dioxide production for a given workload(4);
- A study on physically active students, which showed that supplementing with 8mg of magnesium per kilo of body weight per day produced significant increases in endurance performance and decreased oxygen consumption during sub-maximal exercise(5).
The likely explanation for these findings lies in the fact that that magnesium is required for the activation of crucial enzymes known as ATPases, which are required for energy production A magnesium shortfall also appears to reduce the efficiency of muscle relaxation, which accounts for an important fraction of total energy needs during exercise.
Implications for hockey players
What does this all mean for athletes? The simple message is that a growing body of evidence suggests that maintaining an optimum magnesium status is probably even more important than we’ve previously realised. The latest research on magnesium and lactate adds further weight to the evidence indicating that a healthy magnesium intake is vital for both endurance and anaerobic performance. In the longer term (and perhaps more surprisingly), it appears that an optimal magnesium intake may also be essential for antioxidant protection and for the correct regulation of inflammation, both of which are desirable for athletes, young and old. Although more research is needed to discover the underlying mechanism behind these effects, the take home message is that you should ignore the importance of magnesium at your peril!
Source: various
References
- Scand J Clin Lab Invest 1994; 54:(Supplement 217):5-9
- Am J Cardiol 2003; 91(5):517-21
- Med Sci Sports Exerc 1986; 18(suppl):S55-6
- Am J Cardiol 2003; 91(5):517-21
- Cardiovasc Drugs Ther 1999; 12 Suppl 2: 153-6
- UK Food Standards Agency/COMA
- US Institute of Medicine and National Academy of Sciences
- Scand J Clin Lab Invest 1996; 56: (Supplement 224):211-234
