What are they?
Electrolytes are substances that carry an electric charge and are minerals essential to the diet. Electrolytes of interest to athletes are sodium (Na+), potassium (K+), calcium (Ca2+), magnesium (Mg2+), and chloride (Cl−). Each electrolyte has an important role to play in energy metabolism and muscle function, with sodium being a critical electrolyte for endurance training. During exercise electrolytes maintain fluid balance and muscle contraction by stimulating thirst and retaining fluids, which assists to prevent dehydration; which can bring on a host of symptoms from gastrointestinal stress and cramping, to declines in adequate regulation of body temperature as well as declines in mental focus and concentration.
Where do I find them?
Electrolytes are readily found in a variety of foods, and a diet rich in a variety of veggies, fruits, nuts, seeds, dairy products, lean meats and whole grains should provide adequate amounts to meet daily needs. General sodium intake recommendations are less then or equal to 2.3 grams/day.
For training and racing purposes electrolytes can be obtained through sports drinks (carbohydrate + electrolytes), or through electrolyte only drinks or tablets. Ex. Nuun, GU or salt tablets. Endurance training usually requires electrolyte amounts that exceed daily recommendations of 2.3g/day, especially when environmental conditions are hot and humid.
When do I need electrolytes?
The 3-H rule is helpful in determining when electrolytes are needed during training and racing. Use electrolytes when the weather is Hot or Humid, when you’re going out for a Hard effort and when you’re going out for over 1 Hour. This is especially important if you’re a heavy sweater (have salt residue on your clothing or helmet straps after exercise, or loose a significant amount of water weight during exercise). Also if you’re exercising early in the morning and you haven’t been able to adequately hydrate or fuel up before exercise, taking along sports drink (carb + electrolyte drink) can help to provide carbohydrate for energy and enhanced fluid absorption, along with electrolytes for maintenance of hydration and muscle contraction.
*A carbohydrate rich snack/meal is highly recommended before heading out for exercise that is intended to be longer than 1 to 1 ½ hours in duration.
How much do I need?
Individual sweat rates vary widely and can range from .5 – 1 liter per hour up to 2.4 liters per hour for heavy sweaters. On average .8 to 1 gram of sodium is lost in each liter of sweat, but again sodium concentration losses can be as much as 2 grams per liter for heavy sweaters.
General recommendations are to mix sports drinks to recommendations, which should provide adequate electrolytes and carbohydrate concentrations. If you’re training goals have you regularly participating in exercise over 2 hours in duration then seek out a sports drink that contains 500-1200mg of sodium per liter of solution and 800-2000mg of potassium per liter along with a 4-8% carbohydrate concentration.
Notes:
*These electrolyte recommendations are just that –recommendations. Each of us is individual in our fluid and electrolyte output, our needs for replenishment of fluids and electrolytes each hour, as well as what we can tolerate. There are many sports drinks out on the market so experiment with different products to find what works best for you. And if you’re planning on using nutrition products provided on race day, test them out a few times during your more intense training sessions to assure they will be tolerated on race day. Just make sure to mix drinks to packaging recommendations.
*Research into the onset and prevention of muscle cramping is continuous. Muscle cramps can be can be brought on by a host of factors, which include muscle fatigue, dehydration and electrolyte deficiencies.
