We’ve had a streak of hot weather here in Boston, and most endurance athletes aren’t use to it yet. Be sure to not only drink enough fluids during exercise but also add a little sodium to your pre-exercise stint in the heat if you plan to be outside for a while. The sodium helps retain the fluids in your body (as oposed to have them go in one end and out the other) and can help delay dehydration and enhance your endurance. While on a daily basis you want to monitor your sodium intake, a little extra before hot weather exercise can be a wise choice.
Some possible choices are chicken noodle soup (or any canned brothy soup), V-8 juice, salted pretzels, pickles, ham and cheese sandwich with mustard – or any salted/salty food, before you go. This will be a change in eating patterns for health-conscious endurance athletes who cook their oatmeal without salt, rarely eat canned or processed foods, and have no salt shaker on the table.
You might lose 800 to 1,000 mg sodium per pound of sweat. (Weigh yourself pre and post exercise to figure our how many pounds of sweat you lose in an hour.) While you need not get obsessed about replacing sodium milligram for milligram, reading food labels can give you a frame of reference regarding how much you replace via foods. For example--
A quart of Gatorade offers 440 mg sodium
A can of chicken noodle soup offers 2,350 mg
Eight ounces of rrange juice has only 5 mg
Generally, if you crave salt, you should eat salt. The chapter on Repalcing Sweat Losses in my Sports Nutrition Guidebook offers more information. (See www.nancyclarkrd.com)