I heat up very quickly on hot days which causes my HR to soar. I too love cold weather and don't do well in the heat, but I've registered for a couple of events this Fall and I'm trying to find ways to stay cooler on training rides this summer. I bought a Kool Tie at REI, a tube of fabric containing polymer crystals that expand when wet --- made in Phoenix, and they know heat! I'm already cutting down on my coffee consumption (down from 1 large mug to 1/2 a regular mug), and increasing my water intake even on days I don't ride.

I'm also going to experiment with frozen bandana scarves: soaked in water, folded wet, wrapped in a small ziploc bag and placed in the freezer until ready to use. I'll carry it in the tube pack (NOT in my back jersey pocket where it will melt faster against my back in direct sunlight), it should be thawed but still very cold about midway through the ride.

I'll report back on the success of these measures. If they keep ME cool and comfortable, they may work well for others too.

Since others have done a great job on discussing hydrating and eating, I will focus on the engine. On hot, humid days, derate the engine. The human body is remarkable in its ability to adapt to temperature and humidity but there are limits. So on really hot days, go easier. That provides more blood flow for cooling and less internal heat generation. It is a zero sum game in the human body. We only have so much blood / oxygen transport capability to generate energy that has to be prioritized and apportioned to pedal, breathe, think, cool and digest. As we sweat, we begin to lose blood volume. That means even less is available for our needs.

The key is to stay ahead of the game. Manage your energy and keep drinking and eating before you need it. Once you are in water / electrolyte deficit, the stomach has limits as to how fast it can empty.

I believe that the heat generated to push the pedals is around a 90% loss...meaning that for every watt you generate you need to get rid of 9w of heat.

I raced in Texas for several years. I'll be brief but succienct:

-Insulated bottles packed partially with ice
-More electrolytes than you think you'll need. Hammer's Endurolytes are about the best broad spectrum mineral replacement out there from what I've looked at. You need more than sodium and potassium.
-Colder water is better. Warm/warmer water will either add to your thermal load or reduce core cooling benefits. Physics folks.
-Drink before you need to. Large bottle an hour minimum.
-Ice in the jersey pockets. I also have used a pantyhose leg filled with ice down my back. I avoid the Camelback on hot days because your body is heating the water inside and the camel back is trapping heat in your back (for longer rides...for shorter rides it starts out inversely and provides some cooling benefit).
-If water is available hose yourself down. Evaporative cooling is a good thing.
-Not all helmets vent the same. After much testing I found the Catlike Whisper to be the coolest overall. The Specialized S-works is pretty good as well.
-Adaptation. Know that the first few weeks in the heat will be harder.

Finally while it may seem obvious, I see people standing out in the sun yakking on hot days or riding on the sunny part of the road when there's shade available. Heat is cumulative. Stay out of it more and you'll be cooler.

I don't handle the heat very well so if it gets into the 80s I have to either not ride or slow way down. I've tried many different tactics to ride in the heat but none have ever worked for me. I suffer regardless. So now I just ride slowly and take many breaks or just not go. Or ride at elevation where it is always below 80º.

Most of my life, I've lived somewhere up north with most of it in Michigan. There weather there is cooler but the humidity is higher. My body had to go thru some adjustments with my move to NC. I really didn't notice how my body was acclimating to the warmer climate until I did a weight loss program. I found out very quickly with the first 25 lbs loss that cooler temps of the north bothered me more but the southern heat wasn't an issue. By the time I hit 90 lbs, I lost alot of padding that either my vehicle has very firm seats or I really did lose my extra padding. Had to go with a gel seat cushion and that doesn't solve the problem of long drives.

Normally, I am well hydrated. I found years ago that I just feel better if I drink 8-10 glasses of water a day. I have notice if I'm out riding in higher temps, I do drink more. It's not uncommon for me to stop and take a drink. Follow your body's signal. If you are thristy, you maybe dehyrating.

By the way, they do make an insulated water bottle that fits on the water cage.

I'm 70+ and STILL overeating!!

As for your mileage issue, I think you are right on target. Last August was my first century, trained hard all summer, stretching each each long ride of the week by 10mi until I got to 81 (random mile tagged on:)). Keep at it, dont slack off, toss hill rides and brisk 20's and 30's in during the midweek.....but once each week do the long ride.

Last summer was one of our hottest ever here in Michigan, seemed like it was always 90, sunny and humid. By time August came around we had a day where the temps peaked at 75f and I did the ride no probs.

I have 2 hydration packs I'll mix in with my 28oz water bottle if the heat is getting to be too much.

Try Powerade. It has a better balance of electrolytes than Gatorade. For tough riding just normal dietary sodium intake is not adequate for me. On several long tours (multi-week) we've encountered temperatures as high as 110F for relatively long periods. Humidities have probably been lower than what you are encountering, but we hit some pretty hot humid conditions in Illinois, Indiana, Ohio, and points east. We also hit 109F in the Oregon High Desert and southern Idaho, but the humidity was very low.
We used Powerade almost exclusively.

Start out slow, and work into it. Last summer we left a cool wet Oregon June to arrive in very warm Portugal. While we trained hard by riding a lot of miles, we were not acclimatized at all. We really struggled crossing southern Spain. In Late June and Early July we encountered several days of 104-110F temps. With 4 more days of hard/hot riding before getting to the Mediterranean Coast, we said this is dumb and hopped a train to Valencia and 80 degree temps. The point is start slow and acclimatize.

Earlier this month we were finishing up a 750 mile ride along the California coast by riding back to my Mother-in-Law's home in the San Yoaquin Valley. My wife and I ended up riding in 104 F temps to get there. Again we were using Powerade. We were pretty acclimatized having ended our ride at the Mexican border. Acclimatization makes a lot of difference.

Sometimes it is a little hard to find shade (Oregon High Desert) so drink more:)
http://i783.photobucket.com/albums/y...DSCN0184-2.jpg

Agree with Racer Ex that a better ventilated helmet helps a lot. I found the S works a tremendous improvement. I was getting badly overheated after the 20 mile mark (to the point that my head would be pounding) and with the new helmet the problem all but disappeared. If you do stop, even very briefly, take the helmet off. That helps a great deal as well.

I don't generally have leg cramps riding, but have terrible problems after playing golf once the temps climb much over 90. Not so much on the course but at night afterward. I can relate to the poster who spoke of writhing on the floor in sheer agony. Happens most Wednesday nights during the summer. (They make us ride carts on weekends, so no problem there, but I refuse to give up walking during the week.) Potassium tablets taken in mega doses (I'll eat a dozen of the 99 mg tablets through the afternoon) provides only very limited help. I plan on trying salt tabs next, having just read a NYT article (6/3/12) in which a group of scientists offered that the research on the negative impact on salt has been taken as gospel for years but is really based on old, flawed studies they found to have no merit.

In '07 wife and I were in Spain watching the Vuelta. Magnus was sitting on his bike, so we started talking to him. After a couple of minutes we ask him if he wanted to move over to some shade, since it was a hot day. He said "I am not going to win today and the race was going to be about 6 hours, so 10 minutes was not going to make a difference." Pretty nice guy.

Looks like Idaho off in the distance :D

Don't wait until thirsty to drink....it's too late then. Hydrate well the day before and drink often during the ride. I agree with Stapfam on the salt tablets. Used to work in a warehouse withno A/C and in those days there were salt tab dispensers srategically place throughout the building. If you areerspiring profusely, and I tend to, you won't believe the amount of salt you lose. Despite its bad rap as part of an unhealthy diet, salt is essential. If not through tabs, add it through diet as long as you are sweating it out.

In addition to hydration/nutrition:
1. Small wet towel draped over back of neck
2. Thin sleeveless baselayer
3. Sun sleeves-white
4. Shorts not bibs

"Started with a foot cramp, though it was due to new shoes and clips, then lower back pain started which lead to neck and then a pounding headache. Then my calf’s did not cramp but got very painful."

Your shoes are too tight.

I used to fight forest fires. Salt tablets were standard issue, and we were asked about them to be sure we had some before going to the fire line.

They sure renewed my energy after very extensive sweating. Ever carry a hose line several 100 feet up a steep hill?? Too bad I didn't make it to 70.

I do wonder if they still use salt tabs?

At first I thought this said "I used to light forest fires..." :)

Here's a suggestion I have learned from doing triathlon. Weigh yourself before you go out on a medium, doable ride in the heat. Keep track of how much fluid you consume by refilling/measuring as needed. Weigh yourself immediately when you return. Both weights honest and naked. Beginning - ending - fluid consumed = actual body fluid weight loss.

With this knowledge you should keep you overall weight loss below 2%. This tells you how much fluid replenishment to take. And keep a balance between about 30-50% electrolyte fluid and 50-70% clear water. Water with no electrolyte replacement is a sure recipe for cramps.

I consumed 68 ounces in 52 miles of Texas heat 88-94 degree today, the last 20 into a 20 mph wind. I like Gatorade G2 mixed 50/50 with water and a big healthy teaspoon of plain old salt mixed in. For the entire ride I did 6 of those new Gatorade gel squares and two GU gels.

Nuun

That too - ssshhhh - mums the word - you are the only person I ever told.

I can't take salt tabs, make me puke. We were supposed to take them during water breaks in Pop Warner football practice in the early 70's. My dad told the head coach not to give them to me anymore. Wasn't on that team for long, head coach took advice from no one. The HS here don't use them anymore with all the sports drinks and things for the athletes to take and eat/swallow. I never used them when I coached XC nor dod the HS I went to gave us any salt tabs.

Bill

I won't tell a soul! :)

I got dehydrated yesterday during my first centuy. I pre-hydrated like crazy and urinated a lot at the one and two hour marks but after that very little. I was drinking a bottle of powerade an hour but it wasn't enough. I was very dizzy the last few miles and completely spent at the end. My skin was white with salt from my perspiration. I made it and am happy about that but it was a good lesson.

This is what I do.

I have a foam cooler intended for baby bottles.
It will fit a couple water bottles. I put some water in, freeze it.
Just before I leave, I fill them and throw them in the cooler, and put that in a pannier.
I will have another bottle on the bike. When it gets warm, I take out a cool one, and
take an Endurolyte.
http://www.hammernutrition.com/produ...-energy-drinks

When I feel like I'm cooking, I pour the dregs of the first bottle on my back.
By then, the 2nd bottle is warm, and I pull out the last bottle.

At some point, I'll see a store, and get another bottle, just as an extra.

We also bring fat free pretzels as a snack.

It takes weeks for your body to get used to the heat, some people adapt quicker, especially the young.

We had 94deg up here in Boyne today. I rode a 38mi in strong headwinds most of the ride, plenty of hills and had to wring out my helmet padding of sweat every 15min or less. Couldnt drink enough water until I finally pulled over to a country store and grabbed 2 25oz cold bottles of water and sat in the breezy shade. Dang, it was like a blast furnace today.

I live in hot-n-humid south Louisiana and IMHO a helmet with adequate ventilation/heat dissipation is critical to not cooking your noggin. I wear a Louis Garneau Quartz helmet because it has really big, effective vents. Regardless of what helmet your wear, if you start to get overheated then take the damn lid off. I also try to schedule my longer, faster rides for earlier in the morning. Late afternoon/after work is okay for casual, around-the-subdivision "beer rides" without a helmet (PC incorrect . . . GASP!)