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Don’t Go Running on Empty

Proper hydration and nutrition are especially important during the dog days of summer

It takes more than a blistering summer sun to keep dedicated runners from lacing up and putting in their daily miles. But whether you’re training for a fall marathon or jogging to keep fit, you need to keep properly hydrated and nourished.

Although maintaining proper hydration is important at all times, it’s especially crucial when you’re exercising in the heat, advises Amy Boltz, RD, LDN, Wellness Dietician, Rothman Institute at Jefferson.

“Athletes can lose up to three quarts or about three liters of sweat in as little as an hour of exercise outside,” Ms. Boltz says. “Even losing as little as 1 percent of their body weight can significantly impact athletes’ performance, and greater losses can cause muscle cramps. Substantial dehydration can lead to heat stroke or even death.

“On the other hand, sometimes endurance athletes – particularly people who are running marathons – can over-hydrate themselves, meaning that the level of sodium circulating in their blood becomes too low. That can lead to confusion, nausea and vomiting, muscle cramps and worse.”

Hydration guidelines
The following chart offers some general guidelines on how to drink and when:

In following these guidelines, adds Ms. Boltz, keep in mind:

• Generally, one gulp of fluid equals 1 ounce, and four gulps equals half-cup. So, eight gulps every half hour should keep you properly hydrated.

• Weigh yourself immediately before and after a workout, and then drink at least 2 ½ cups of water for every pound lost in sweat.

• If a scale isn’t available, measure your hydration by monitoring your urine, which should be light yellow and odorless. Dark-yellow urine indicates dehydration.

• Don’t wait until you’re thirsty to begin drinking. If you’re thirsty, you’re already dehydrated.    

• Pre- and post-activity consumption of fruits and vegetables rich in water – for example, watermelon, berries and tomatoes – can also help keep you properly hydrated. 

• To prevent over-hydration, sports drinks that are 6 to 8 percent carbohydrates, such as Gatorade® and POWERade®, are better than water for activities lasting more than hour because they can replace carbohydrates and electrolytes necessary to prevent low-sodium levels. To counter-balance sodium loss even faster, add ½ teaspoon of salt to a 32-oz. sports drink.

• Daily consumption of foods high in salt, such as pretzels, soups and tomato juice, can also help prevent sodium levels from getting too low.

Nutrition guidelines
Carbohydrates, protein and fat are the three sources of nutrition. Everyone, including athletes, must draw from all three of these sources, but in proper balance. For runners and other endurance athletes, recommends Ms. Boltz, that balance is: 

• 55 to 65 percent from carbohydrates – Healthy options include whole grains (whole wheat breads and cereals), fruits, starchy vegetables (potatoes, corn) and low-fat dairy products (which also provides protein, as well as calcium to keep bones strong).

• 15 to 20 percent from protein – Healthy options include lean meats (skinless chicken and turkey), fish and beans, as well as the aforementioned low-fat dairy.

• 20 to 30 percent from fat – Healthy options include olive oil, canola oil, peanut butter, avocados and seeds (sesame, sunflower and pumpkin).  “A lot of runners, particularly, forget about fat, but it is necessary to deliver such vitamins as A, D, E and K throughout your body,” Ms. Boltz stresses. “Healthy fats also enable marathon runners to meet their very high calorie needs without adding a lot of volume to their food intake. But minimize your consumption of saturated and trans fats, which are unhealthy. ”