Q: I am a 17 year old CC runner currently running 75 miles a week. During the day here (suburban Chicago) it gets up to about 85-95 degrees. When I do runs at this time after about an hour white foam starts to build up at the outlet of my shorts and runs down my leg. Preparing for Boston Marathon? Here Are 4 Tips? —Nate
A: How to Increase Mileage Running warm weather; sweat is one of the most important of these. The salt concentration in sweat is very variable, depending on a number of conditions. Early in the summer, before you have adapted or acclimatized to the heat, sweat will have a high salt concentration. As your body adjusts to training in the heat, the salt concentration in sweat will decrease.
Sweat is most effective as a coolant when it evaporates from the skin; this evaporative process does not work well in humid weather (like summer in Chicago). Instead of evaporating, the sweat will drip off of you.
Putting all of this together, running on a hot humid day, especially during the first week or so of hot weather (or on random warm days in the fall), will cause salty sweat to run down your legs.
First Boston Marathon? Here‘s What to Know well hydrated. Each pound that you lose on a run indicates a fluid deficit of 16 ounces; you should be replacing this fluid during and after your run, so you don't start the next run already mildly dehydrated. Dehydration impairs the cooling process; at a minimum, this will adversely affect performance. At a greater level, dehydration can lead to serious consequences, even death.
Electrolytes are also important when you are sweating heavily for prolonged periods of time. Salting your food will help replace some of the salt that you have lost. Many of the sports drinks have sodium and other electrolytes added.
How to Increase Mileage Running!
