I agree with most of your post with a couple of exceptions. First, I think hyponatremia is extremely rare with cyclists. I've heard of it, once with a friend who was part way through RAAM and had to be hospitalized and another time with a guy who was doing a 150 mile climbing ride on a hot day and he wasn't eating. I think if a cyclist is eating or at least taking electrolytes the risk is minimal. I know people have died from it during marathons, but these are people who spend 6+ hours running with nothing but water.
The other thing is the "drink only when thirsty" idea. This may work for some but certainly not everyone every time. When I do a hot climbing ride I cannot keep up with the fluid loss and have to start forcing water early in the ride. I typically come home from a hot ride (6 hours, more or less) 5 or 6 pounds lighter. I tried to ration water once, still drank a bunch, and was 11 pounds lighter after the ride. To me, thirst doesn't enter it and I must make a conscious effort to drink.

My fastest 200k ever was a 11pm departure out of San Angelo, TX. July 14, 2017. 07:30 elapsed time, solo. I'll tell you what, I did that ride several times at night, and it's darned spooky out there in the middle of frickin' nowhere, with not a single car from midnight to 5am.

IIRC, it was still over 100F when I departed. But it's a dry heat, they say ROFLMAO. Dry heat sucks the water out of your body faster than you can drink. At least at 11pm-6am the sun isn't killing you.

It's a left out of the parking lot, then a right onto the highway, straight down to Sonora with nothing in-between except a closed down Eldorado, fuel and water at the Sonora convenience store, back north on the highway, left, right. Six turns, 201km. Nothing to keep you company but the wind, which guaranteed will be blowing one way or the other.

Cheers, from cool and green Oregon :)

Yes, just a few hours ago I almost collided with a deer. I was on routes where I know the roads very well so I know where the deer tend to be. Not nearly as lonely as the route you cruised at night. Skunks and rattlesnakes is my biggest fear. It was great to get out of the hot sun and the old boring route is like new at night it feels like a completely different route. I haven’t cycled at night very much so this is new and keeping the sport fresh.

I agree with what others say, it's the humidity as much as the heat that makes it so tough to exercise when it gets hot. Admittedly here in the(usually) cool UK high temps are rare. Last week did a ride in around 85F which for where I live is hot but it was the humidity which was tougher. Somewhere like Aus where it's dry heat not so bad imo. For what it's worth I love the hot weather, time to move if I can persuade the family!

To be sure I always have cool or cold water I carry at least two insulated bottles. One is semi-frosty from sitting overnight on the top shelf of the fridge under the cold air vent from freezer. It'll have some frost but not frozen solid. It'll stay cool for the 60-90 minutes it takes me to drink it.

The second bottle is frozen solid overnight. By the time I've finished the first bottle the second is thawing and will stay cold for a couple of hours. Depending on my route I'll stop at a convenience store to refill with a bottle of generic sports drink poured into the remaining chunk of ice in the second bottle.

If I'm not sure about supplies on a route I'll take a third bottle or Mylar pouch, also frozen, in a jersey pocket.

I also have a double insulated stainless thermos that fits my water bottle cages. Sometimes I'll fill it about 1/2 to 2/3 full, freeze it, and top off with plain water. It'll stay icy 12-24 hours depending on ambient temperature. Or I'll fill it with hot coffee for winter rides. It's heavy but worth lugging for really hot or cold rides.

I still wonder if a deer was the cause of my skull be cracked in three places last year. I have amnesia for everything that happened 10 or 15 minutes prior till I got put in my room at the hospital. One of the fleeting little scenes that went through my head for a period of time after were of a deer bounding off through the woods.

If you ride solo, think about whether you might want another to know when to expect you back or even share your location with them via your smartphone. My wife had just checked my location on her phone, saw I was stopped in an area I don't normally stop in and was about to call 911 when the people that found me called her. So simple things of just letting another person know and location sharing with a smartphone can work.

Anyhow.... back to the subject. Your gravel roads out there look great. Wish the few we had here were like that. Here, they tend to be six inches deep in wash gravel.

The gravel here is hard packed so it is fairly smooth. But I have to watch those soft spots that the tires like to dig into. I have a sibling that lives nearby that can track me on her I-phone. I should tell her when I’m out biking at night. People out here are friendly if I’m found wrecked and in tatters I think they would help :innocent: ...

My wife got hyponatremia on one of our 10-day backpacks. The weather was cool and showery. We hiked maybe 6 hours. After we made camp, she was obviously not OK, pale, nauseous, confused. It was a bit terrifying. We talked and I finally figured it out: she'd been drinking to the timing pattern she used on long bike rides, except that it was cool and she wasn't sweating. I'd only drunk about 1 pt. all day and felt fine. I gave her 2 Endurolytes with a little water and she was fine in 1/2 hour. Drink to thirst.

If you're not thirsty and are hammering water, you are definitely at risk. No matter how much water you're drinking, and about a liter per hour is all that's possible, you need to take enough electrolytes that you're slightly thirsty because that indicates proper balance and should produce slightly better performance and recovery. Definitely don't ration water. Why would one do that? We should all know that water does more good in the body than it does in the bottle. If you're low on water and worried, drink it.

I have a little heat exhaustion story which might be helpful to someone. My wife and I were on our honeymoon hike, long ago, in the Olympic National Park. It was sunny, amazing. About 5 miles up the trail, we came upon a fellow with all the symptoms of a divorced lawyer and heat exhaustion. He had his ~12 y.o. kid for the weekend. They had ~$1000 worth of new REI gear. He was wearing a down parka, pale and sweating. We were in shorts and T-shirts. He was not OK. Actually the first person we met was his son, who told us about his dad, up the trail. He'd been sent back down the trail to look for water. We asked the dad if he had water and yes he did but he was afraid to drink it because that was all they had. We gave him some electrolytes, talked him into drinking the water, gave him some more, and walked up the trail with them for an hour. He was fine, so we dropped them and took off. The trail we were on had stream crossings every mile or so, typical of the Olympics. Back in the day, I never carried water in the Park, just a handy cup.

Feeling cold and yet sweaty on a warm day is not what one expects from heat exhaustion, but there it is. Untreated heat exhaustion becomes heat stroke, which becomes a medical emergency.

That is why I specified eating or taking electrolytes. Of course if you flush yourself out you are at risk but the things I have read say if you eat or take electrolytes you should be fine. I never take that risk.
The day I was rationing water was an 85 mile loop with over 8500 feet of climbing, front loaded. I started with 2 large bottles but didn't want to stop and refill and lose the group, I know, dumb.Once into the mountains there was no water until the designated fill stop and by that time I was screwed. No way to catch up with hydration for me and so I suffered and struggled the rest of the day. I drink more than most, a lot more than many people I ride with. Yesterday I rode less than 4 hours, maybe 90 degrees tops, and lots of climbing. I drank about a gallon and when I got home I just kept drinking to try and re-hydrate. Still thirsty this morning.

And we always worry about dehydration. Too much water never really crosses the mind that much. Hiking in the desert mountains in Big Bend NP I ran across one water bottle only guy with no backpack or anything. He was trying to get liquid out of cactus and had thorns sticking in his lips and mouth. Idiot! I was heading down the mountain at least 2 plus hours to go. I gave this fellow a bottle of Gatorade that I could spare I told him hike back to the trailhead now! Oh hell no he insisted on making it to the peak which was miles away I told him you are not going to make it. Save the bottle and ask for liquid but if they refuse you it’s because they are at minimum. I’m not his dad so I left heading back down. If he was a teen or a kid I would have been more insistent., Back home I looked at the NP reports they didn’t pull a corpse off the mountain so I guess he didn’t die.
I never thought much about hyponatremia because I’m always in a sweat but in a cool weather area or when we have cold days in winter it is something to seriously consider.

I was descending a fire road on my mountain bike and there was a couple on bikes climbing and they were arguing about something. I noticed they only had 1 bottle between them. I got to the bottom and climbing back up I found the guy lying on his back in the middle of the road. I had lots of water (it was hot) and I gave him some and he got up and seemed to be ok so I took off and eventually caught up to his wife/girlfriend, she had their water, and I told her that the guy was hurting back there. She said something like, "He'll be ok". Great, see ya.

My fellow club member David became the first rider over 60 to finish the RAAM. He failed on his first attempt due to hyponatremia. He gained about 15 pounds of water weight and he's a little guy. He couldn't put his shoes on because his feet and legs were so swollen.
The next year he had figured out the nutrition and hydration and finished with some time to spare. The next time he did it he became the first rider over 65 to finish and he said it was relatively easy.

Just an aside: Do you run into some large feral hogs at night?

I almost never drink straight water for a ride. I've always got a mix in my bottles that includes a little bit of electrolytes. However for those that do drink straight water, they probably should start thinking about a source of electrolytes when going from their third bottle to forth bottle of straight water. Because after the fifth bottle of straight water they can be in dangerous territory if those five bottles are consumed over a relatively short period of time.

The electrolytes don't have to be in your bottles. You can just eat something or take a tablet. Plain table salt is an electrolyte. Sodium, calcium, potassium, chlorides, phosphates and magnesium are all electrolytes. Some more than others. But even a salty snack along the way will help. I just prefer to put it in my bottles like I do my carbs. It's just too bothersome for me to pull out a gel or pill while riding. Not that I can't do it, just that I don't care to since bottles are more convenient.

However more is not better. So be careful not to get into the idea of just simply adding huge amounts of electrolytes into your hydration/feeding regimen while riding. I don't use Gatorade, PowerAid or other pre-made sport drinks because I feel they have too much electrolyte. At least for me they do.

No but I’m sure I will. I know where the tanks aka ponds are were the pigs like to be that are near the road. They usually run away from you but if all confused could run into you and with those tusks it could turn out bad. Nasty crop destroying pests but if you shoot the 80-100 pounders they make great bar b q.. The big fat 300-500 pounders just stink. No natural enemies even coyotes won’t mess with a 500 pound angry mama sow.

Heck, I drink straight water out my hydration pack never thought of adding electrolytes. I have the powder packets that you add to water. I’m going to start adding them. I do eat Ritz peanut butter crackers at minute 90-120 that are salty so I guess that helps. When I used Gatorade I dilute it 50/50 with water. To prevent cramps why you cramp I don’t know but I learned the hard way. I have had straight water in the hydration pack and a bottle of Gatorade in the bottle cage and figured it was being balanced out with the straight water.

They’ve removed the water coolers on our golf course due to the virus......I walk the 18 holes so I put 3 of my cycling water bottles in my golf bag. I also take electrolyte capsules with the last two bottles. Those really help to keep my energy levels up. I’m not a big perspiration person but my clothes are soaked at the end of each round.

Yesterday I rode the bike for about 4 hours with temperatures pushing 90 the last hour along with high humidity all morning. I only used two bottles of sports drink. I need to drink more when but just don’t. I used to take a swig every 10-15 mins but have gotten out of the habit. I do a better job of drinking while climbing.

103 right now. Going to night ride leave about 8pm .. drink a quart of Gatorade before I take off.

Went for a short 19 mi ride in the 92F today. Going for a 15 mi or so ride with my wife after dark tonight on the bike trails. Will be her first night riding here in Ohio.

Temps tend to be more mild here. 70's and 80's in the summer.

I have ridden in 100+ temperatures a couple of times. It isn't too bad as long as one keeps moving. Make sure one brings lots of water.

I hit upper 90's and low 100's for a 150 to 190 mile ride a few years ago. Whew, it was HOT midway through the ride, and I was drinking every drop of water I could get. Fortunately it cooled down somewhat even by late afternoon, and into early evening.

My friend in East Texas tells me she is afraid if she falls off the bike the pigs will have her for lunch.

They can be aggressive but most of the ones I come across run away If not cornered.

Accuweather's forecast for Seattle for July shows a quite a few days around 80. Mostly 70's.

Guess with San Diego (Coronado) and Santa Cruz in my homeowning past, I'm just a left coaster.

I could not be a cyclist in southern summer heat and/or humidity.

But I couldn't live there either, so best for all.

I came across one rattler sunning himself on the shoulder in the early morning sunlight. I just swung out into the empty highway and gave him the shoulder. Big fat dude. One snake avoidance tactic I did use, when stopping to take a leak at night, was to just stick to the middle of the blacktop. I could see/hear a car from a mile away, so that wasn't a concern.

The locals told me they'd be most concerned about feral dogs, but TBH the locals were home in bed at 2am, not on the road to Sonora.

The poor dog that chases me just wants to run. The poor thing is half blind and slow. I stopped and let it catch me and the dog was smirking and all happy. Trotted back home all content...

True. We have a serious problem with feral hogs in Texas. I haven't hunted in years but I'd consider it for the feral hog problem. They're a menace to the entire ecosystem, not to mention dangerous to hikers or people who work outdoors.

The state will give ranchers money to hire helicopters with shooters in them to shoot feral hogs. Sometimes I can here a helicopter then gun fire shooting hogs. When My family had a large ranch I hunted hogs all the time. We even had hog traps. We would also let people come over a hunt as many hogs as they wanted for free. Just to get rid of them. Like canklecat said they tear stuff up. They will ruin your whole yard and will even eat every seed in a farmer’s field right after it has been planted. Urban legend has it in S Texas this farmer lost his hog farm so he just let his 500 hogs loose and that started a boom in the feral hog population. No natural predators and they are a tough animal and smart.

Wunderground's Map said 112-116°F along my ride home yesterday afternoon. But there are plenty of places to stop and get a cold drink if I need it.

Here's how the pros train for the heat: https://trainright.com/badwater-lessons-preparation/

Thanks for the link. About the only one I've tried is running the heater in the summer. That wasn't to acclimate my body.

At the time my vehicle's radiator was clogged by the water here. So I delivered pizza in the summer running the heater. Believe it or not it kept the engine from popping a cork. Until I saved enough in tips to have the radiator rodded.

Nowadays my strategy is to pay attention to the weather predictions and the messages my body is telling me. Slow down when you have to. Ride faster at other times. Try to enjoy the ride fast or slow.