Nov 11th, 2013
Author: CrossFit CDR
Category: CrossFit CDR
Nutrition Corner: Magnesium
Many of you have probably heard the word magnesium, and may even take the Pure Pharma M 3 supplement, but besides the fact that its a mineral, what does magnesium actually do in our bodies? Does it really help in increasing athletic performance?
Magnesium is the fourth most abundant mineral found in the body, with about 60% of it found in bone, 26% in muscle, and the rest is inside our cells or in the bloodstream. Magnesium is an essential cofactor for more than 300 enzymatic reactions in the body! These include:
- DNA and RNA synthesis
- ATP production–our bodies energy currency
- Fatty Acid and Protein synthesis
- Glycolysis (Breaking down of carbohydrates for fuel or storage)
- Proper hormone functioning–including proper bone formation and regeneration
- Neuromuscular transmission and activity
One very important role of Magnesium for athletes is its relationship with calcium in contracting and relaxing our smooth (heart and organ) and skeletal muscles. Magnesium acts as a “natural” calcium blocker, because as magnesium becomes depleted, calcium can increase in the body. If an imbalance of our Mg: Ca ratio occurs, it can impair the proper functioning of our muscle cells.
Signs of sub-optimal Magnesium Intake
- muscle cramps, tremors, twitches
- regular or excessive fatigue
- irritability or lethargy
- frequent mood swings, including depression
- restless legs at night
- pre-menstrual bloating
Does it help with Athletic Performance?
Currently, many studies have been conducted testing magnesium’s role in athletic performance. In one 3-month study conducted on a group of women who were given diets deficient in magnesium, the results showed a significant relationship between low dietary magnesium and decreased levels of athletic performance. Low levels of magnesium impaired functioning during exercise by increasing the amount of oxygen needed to generate ATP (ATP turnover can be as high as 15 kg during exercise!), as well as lead to increased energy costs due to the decreased efficiency of muscle contraction. These effects were seen in all women despite their level of athletic performance.
Sources of Dietary Magnesium
Many people in the US currently do not receive the recommended daily allowance (RDA) of magnesium, which is 350 mg for both males and females. Below is a list of food sources that are high in this essential mineral:
- Halibut, 3 oz 90 mg
- Almonds, 1 oz 80 mg
- Swiss chard, 1/2 c. 78 mg
- Oatmeal 1 c. cooked 55 mg
24 Days of Christmas Challenge!
Our nutritionist, T-mac, will be doing another food challenge to get all of you holiday ready! This one will be different from past challenges to keep all of you committed! Here are the details:
- When: Dec. 1st-24th
- How many challengers: 24
- How it works: Each participant will be given 3 warnings: 1st=warning, 2nd=200 burpees, 3rd=YOU’RE OUT!
- There will be incentives to tattle on each other if you are not sticking to the plan!
- If you are interested, talk with T-mac ASAP
Workout of the Day
Strength: 5 Rep Max BackSquat
Row 1 K
7 ring dips
Sign up for class here
For more information on the effects of magnesium and athletic performance, check out the research article here
For a healthy and magnesium-rich recipe click here!
For more information on magnesium and food sources, check out this Health Professional fact sheet here
Erdman JW, Macdonald IA, Zeisel SH, eds. Present Knowledge in Nutrition. 10th ed. United Kingdom: John Wiley and Sons Ltd; 2012
Lukaski HC, Nielsen FH. Dietary magnesium depletion affects metabolic responses during submaximal exercise in post-menopausal women. J Nutr. 2002;132:930-935.
Raymond JL, Escott-Stump S. Krause’s Food, Nutrition, and Diet Therapy. 11th ed. Elsevier Health Sciences; 2003.