Macrominerals and Electrolytes

Dietary minerals are inorganic elements that the body needs to function properly. Macrominerals (like calcium, magnesium, potassium, and sodium) are required in larger (milligram to gram) amounts in the body; whereas, the trace minerals (like iron, iodine, chromium, selenium, and zinc) are only required in small amounts daily.

Several of the important macrominerals also form the body’s much-needed electrolytes. Without giving you a refresher course in chemistry, most simply put, electrolytes are mineral salts that carry an electrical charge (either positive or negative). Electrolytes maintain nerve activity, muscle function (contraction and relaxation), and blood acid-base balance (i.e., pH).

The importance of macromineral supplements in athletes is commonly overlooked—as most tend to believe that we get enough from our diet. Many people also believe that the kidneys can make up for shortcomings in the diet by selectively regulating fluid and mineral balance to maintain normal blood pH. Certainly, under normal healthy conditions, diet and kidney function may suffice to balance macrominerals. However, consuming a high protein diet, as well as stress from exercise, work, and/or caloric restriction can increase the “acidic load” in the blood and increase macromineral/electrolyte requirements. Beyond increased “acidic load”, heavy sweating during intense training can rapidly diminish blood electrolytes, which can further throw acid-base balance off.

In this month’s supplement in focus we have honed in on the macrominerals and electrolytes that are important for every bodybuilder and strength athlete to consider.

Calcium (Ca) is very important for bodybuilders. Not only does it maintain bone health, but also it is intimately involved in muscular contraction/relaxation (needed for power). Research also indicates that adequate calcium ingestion increases fat metabolism, decreases fat storage, and helps with absorption of macronutrients (like protein). Recent evidence also shows that calcium can trigger greater anabolic testosterone release after a bout of heavy training.

Sources: Dairy products, legumes, tofu, salmon, sardines.

Signs of deficiency: Early symptoms include, muscle cramps, brittle nails, twitching eyes, and yellowing of teeth.

Dosage: For best results, you should take in1000-2000 mg of calcium citrate daily. The body can only absorb about 600 mg of calcium at a time, so single 600 mg doses work best. Remember to adjust your dose based on the amount of calcium you get from dietary means. Note: Since calcium can interact with the absorption of other drugs and nutrients, make sure you take it 2 to 3 hours before or after taking other supplements.

Magnesium (Mg) is the fourth most abundant mineral found in the body and is vital for proper nerve and muscle function. It is known to help keep the heart beating regularly, it maintains bone health, and supports the immune system. In terms of muscle growth, Mg is tightly involved in regulating blood glucose levels and protein synthesis. Research shows that many North Americans (especially athletes) are deficient in Mg.

Sources: Halibut (fish), almonds, cashews, green vegetables (e.g., spinach), legumes, whole grains

Signs of Deficiency: Loss of appetite, fatigue, muscle weakness, muscle cramping, involuntary muscle contractions.

Dosage: Although there are no reported dangers with excessive Mg ingestion, you may note stomach cramps and diarrhea with too much. The upper limit for Mg ingestion is about 350-450 mg per day.

Potassium (K) is needed for proper muscle, nerve and organ function and aids in maintaining healthy bones. It has also been linked to maintaining healthy blood pressure. Specific to bodybuilding, potassium supplementation has been shown to decrease muscle soreness and aid in maintaining water balance and normal muscle contraction, especially under conditions of caloric restriction (where deficiencies may occur). For those who eat a well-balanced and mixed diet, potassium supplements are unnecessary. However, those undergoing strict dieting (like competitive bodybuilders) may find supplementing potassium very useful.

Sources: Citrus fruits, bananas, tomatoes, milk, potatoes, and legumes

Signs of Deficiency: Loss of appetite, fatigue, muscle weakness, muscle cramping, involuntary muscle contractions.

Dosage: Taking too much potassium can result in cardiac arrest and be fatal. Be sure to consider your fruit and vegetable intake before deciding to take a potassium supplement. For those undergoing a strict diet that is near void of fruits and vegetables, taking up to 500 mg per day in 3-5 single 100 mg doses should suffice.

Sodium (Na) receives a lot of negative press, as excessive amounts can lead to heart disease and stroke. In terms of bodybuilding, excessive sodium in the diet leads to water retention and a bloated appearance. However, sodium in proper amounts is necessary for normal muscle and nerve function and body fluid balance. Athletes should be aware of their sodium requirements, as electrolytes are lost with sweating. If you only replace fluids with water, then a sodium imbalance may ensue and result in a condition called hyponaturemia. For bodybuilders, depending on the time of season, you may limit or increase sodium intake in an effort to manipulate body water levels.

Sources: Table salt (NaCl), sports drinks, soda pop, pickles, meat, dairy, eggs, smoked salmon.

Signs of deficiency: Muscle weakness, muscle cramps, low blood pressure, dizziness.

Dosage: Although sodium is very important for normal body function, there is generally no need to take a sodium supplement. In fact you may have to try to limit your dietary intake of sodium to keep it under 3000 mg per day. A healthy rule is to take in no more than 1 mg of sodium per calorie of food ingested (to a maximum of 3000 mg of sodium per day).