by Sarah Schlichter
As runners, we most often hear about the macronutrient groups, like carbohydrates, for performance. There’s a good reason for that—carbohydrates act as the most efficient fuel source and provide sustenance for endurance exercise. However, if you think of carbohydrates like the gas that fuels your car (or exercise), there are many other teammates (nutrients) that are needed alongside, acting as the steering wheel, blinkers and headlights. In other words, we also need other micronutrients to perform efficiently and effectively.
In relation to macronutrients, micronutrients are vitamins and minerals that we need in smaller amounts. Don’t let that fool you though—they still play a significant role in body functioning and performance. They are essential because our body can’t make them—meaning we need to get them from our diets. Antioxidants, like Vitamins A, C and E, help protect against oxidative damage during exercise and are crucial for our recovery. Antioxidants help our bodies strengthen and repair cell and muscle tissue, allowing us to perform exercises again and again.
Micronutrients are the vitamins and minerals that our bodies need to perform properly.
Electrolytes, namely sodium, potassium, magnesium and chloride, are a subset of key micronutrients we need before, during and after exercise. These are the predominant substances we lose through sweat and activity. Electrolytes are crucial for maintaining and balancing body fluid, while allowing for optimal performance. While we want to replenish fluid stores before, during and after exercise to prevent dehydration, we also want to replenish electrolytes as well.
Sodium, potassium and magnesium are the common electrolytes lost in sweat. We cannot stay adequately hydrated without sufficient electrolytes. Your personal sweat rate, the weather and humidity, time and intensity are all factors that will influence the amount of electrolytes needed. It may vary from person to person, and it’s best to meet with a professional to determine the ideal amount you need for proper performance. Sodium is helpful for water retention and preventing the loss of excess fluid during exercise. It should be consumed along with other electrolytes to assist in proper fluid balance. Potassium is important for the transport of fluids and nutrients in and out of our cells, nerve impulses and muscle contractions. Many runners may be familiar with muscle cramping, which could be a symptom of inadequate potassium or imbalanced electrolyte levels. Magnesium tends to fly under the radar as an electrolyte, compared to sodium and potassium. However, magnesium plays key roles in energy balance and metabolism, oxygen and electrolyte uptake and helping to decrease muscle cramping. These electrolytes work together to help maintain fluid uptake, fluid balance and promote muscle contraction throughout exercise. A deficiency in one or an imbalance could lead to dehydration or overhydration, adverse symptoms and poor performance.
Dried fruit, like raisins and dates, are popular “real food” choices among runners due to their carbohydrate and glucose content, providing rapid energy. We know raisins are an optimal carbohydrate-rich snack for before, during and/or after exercise. A study in International Society of Sports Nutrition found that raisins and sports chews promoted more carbohydrate oxidation and improved running performance vs. water alone.
Raisins not only provide rapid energy, but also heart-healthy vitamins and minerals.
Raisins are also advantageous because they have a range of key micronutrients that can benefit athletes. Raisins are high in potassium, which along with muscle contraction and fluid balance, also helps with heart health and blood pressure. A 1.5 oz. serving size of raisins offers nearly 10-15% of your daily potassium needs (about 322 milligrams). Many endurance athletes may also prefer to sprinkle some salt on their raisins or dried fruit to enhance sodium intake as well. Raisins are a great vehicle for providing both sweet and salty tastes, according to your preference.
Raisins provide small amounts of other micronutrients, like B-Vitamins, calcium, magnesium, zinc and Vitamin C. A serving size of raisins also provides about a milligram of iron, nearly 5% and 10% of women and men’s needs, respectively. Raisins also contain a range of polyphenols, which act as antioxidants that help limit damage to our cells and muscle tissue. Don’t discount the power of dried fruits to help manage electrolyte balance during your next race. You may find that raisins are great for instant energy and can complement your other fueling products during exercise. Make sure to stay hydrated with water, but also consume enough electrolytes as well.
Sarah Schlichter is a Registered Dietitian with my Master’s of Public Health in Charlotte, NC. She works in nutrition counseling and consulting, and blogs at Bucket List Tummy.