1. Health

When cycling in the heat, take steps to stay cool, safe

fat and tired girl riding bicycle
fat and tired girl riding bicycle
Published May 28, 2015

In more than 40 years of riding, heat was never a problem for me. My legs cramped, but it was nothing I couldn't stretch out during a ride. A week before last month's Spring Classic, hosted by the St. Pete Bike Club, I tapered off my training and prepared for a century ride with a modest goal of shaving a few minutes off my best time.

That day's high was forecast to be 90 degrees. The first 25 miles were easy, as I was with a strong group of riders who all shared the load. But they didn't stop at one of the early rest areas, called SAG stops. The club had six of them for the ride, offering water and food. My group finally pulled into one at about the 40-mile mark. I was drinking during the ride but only when I felt thirsty. At about 65 miles I took a strong pull for a mile or so and remember thinking my goal was imminently doable.

We skipped the next rest stop at around 70 miles. Shortly thereafter, I realized I needed food. Unwrapping an energy bar, I lost contact with the group but kept a good pace and caught them at the next rest stop at about 82 miles. I was thirsty but still confident.

At 90 miles, my cramps were getting harder to stretch out. When we took off from a traffic light, suddenly one knee went sideways. I had no idea what was happening. By 94 miles, both legs were rubber. My knees were flailing side to side so much that I was afraid of losing my balance and falling off the bike. I lost all leg muscle control. I had to call it a day. By the time I got home, I literally could not move without my legs cramping severely. My wife tried to get me to relax by breathing as if I were about to give birth. He-he-he-ooo.

"You had severe dehydration," said Dr. Eduardo Martinez, an internist in Largo and a cyclist for about 20 years. He rides an average of 170 miles a week and said there is no substitute for experience.

"If you're going to do a big ride in the heat, you need to practice riding in the heat," he said. And you need to understand how your body reacts to hot weather. I'd add this: Don't get cocky. After eight years in the Texas heat and 20-plus years in the hot and sticky Washington, D.C., summers, I thought I could handle anything.

Martinez has found that, for him, magnesium is key. He takes as much as 1,000 milligrams on days he has big rides. "Magnesium has saved me when my legs were locked up years ago on a ride," he said.

Some medical experts say that up to 80 percent of Americans have chronic magnesium deficiency because of their diets. This deficiency can cause depression, sleeplessness, anxiety, muscle weakness, abnormal heart rhythms and low blood pressure. A blood test called Magnesium RBC can diagnose a chronic deficiency.

First and foremost, you need to drink, something I don't do much, even on a normal day. And during warm day rides, drinking is more important than eating. The body's systems can't function when you're dehydrated, as I discovered.

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Ideally, you need to drink before the ride — two glasses is the oft cited maxim. And during the ride, thirst is not a reliable guide. I wish last month I had followed my past practice of drinking every 10 minutes during long rides. You don't need much liquid each time, just a few ounces, but keep constantly hydrating.

You needn't replace all the water you lose during exercise. Sweating away 1 or 2 percent of your body weight is not cause for concern. But if after a ride your urine is dark or you have a crusty white film on your riding clothes, Martinez said, you're losing excessive salts and water. Energy drinks with electrolytes help replace what you lose when sweating, though many riders prefer to dilute these sweet drinks because they can upset stomachs.

Martinez said he found pickle juice effective during his last Six Gap ride in Georgia. Some riders there swore by mustard packets (yes, those little shots of mustard you get with your hot dog).

Caffeine, often claimed to be a diuretic, may help your ride. English researchers found that caffeine increased absorption of glucose in the intestine.

You'll need to experiment to see what works for you (or, in my case, what didn't work). Elite professional riders can drink 9 liters of water in a six-hour stage race.

But experts agree that the old saw about drinking eight glasses of water a day is still valid. It seems like a preposterous amount to me, especially in the winter. But then in the winter, my legs don't go wobbly and I don't lie on the couch screaming about my cramps.

One other hot weather tip: Use sunscreen. I'll soon have a divot on my nose when they remove my melanoma in situ, the mildest form of skin cancer.

Yeah, summer is not the time for sissies.

Bob Griendling is vice president of the St. Petersburg Bicycle Club and a member of the Mayor's Bicycling and Pedestrian Advisory Committee. He blogs at Contact him at


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