It’s summer! The days are longer, the weather is warmer, and kids are off from school. We all want to play more in the summer, taking advantage of longer days and nicer weather. With our coastline and mountains, San Diego is a Mecca for outdoor activity. Surfing, swimming, in-line skating, running, bicycling, mountain biking, rock climbing, and a wide variety of team sports are the tip of the iceberg for our summer activities.
We’re all taught to make sure we drink enough water during exercise. Many health care providers recommend drinking at least eight glasses of water per day, and more during the summer or while exercising. What doesn’t get mentioned is that drinking much more than this can dilute essential minerals and electrolytes which can cause a whole host of problems. I learned this firsthand while on a bicycle tour in the midwest during one of the most severe heat waves Missouri has seen in June! I found myself drinking nearly 3 gallons of water daily to keep from being thirsty, which filled my belly so much it was hard to eat enough calories to sustain 70-mile days on a bicycle. Even eating salty snacks, salting my food more than usual, and taking a double dose of my usual potassium, multi-mineral, and calcium supplements had me barely keeping up with electrolytes. Several people on the ride spent an afternoon in the emergency room for an IV of Ringer’s solution after suffering severe heat exhaustion and electrolyte depletion. This type of emergency can easily be avoided if you pay attention to electrolytes in addition to fluid intake alone.
What are electrolytes, and why do we need them? salt tablets for runners
In chemistry, every atom has a certain number of protons (positively charged) and electrons (negatively charged). A stable atom has an equal number of protons and electrons, and has no electrical charge. An ion is an atom that has an uneven number of protons and electrons, giving it a positive or negative electrical charge. An electrolyte is any substance containing free ions that behaves as an electrically conductive medium.
In physiology, the primary ions of electrolytes are sodium (Na+), potassium (K+), calcium (Ca2+), magnesium (Mg2+), and chloride (Cl−). The electric charge symbols of plus (+) and minus (−) indicate that the substance in question is ionic in nature and has an imbalanced distribution of electrons.
Both muscles and nerves are considered electric tissues. Muscles and nerves are activated by electrolyte activity between interstitial fluid (fluid between the cells) and intercellular fluid (fluid within the cells). Electrolytes may enter or leave a cell through the cell membrane and are required for a variety of cellular functions. For example, muscle contraction is dependent upon the presence of calcium (Ca2+), sodium (Na+), and potassium (K+). Without sufficient levels of these key electrolytes, muscle weakness or severe muscle contractions may occur.
Electrolyte balance is maintained by intake of electrolyte-containing substances, and is regulated by hormones as well as by the kidneys. back to top
Which electrolytes do we need?
While sodium gets a bad rap from the people concerned about blood pressure, it is actually required for a variety of cellular functions and we can’t live without it. A human being requires approximately 500mg of sodium per day for basic physiological functions. Sodium is one of the minerals required for nerve impulses to occur (nerve impulses facilitate every message from the brain to our muscles and internal organs). It is also important for maintaining appropriate blood volume.