Take the 2-minute tour ×
Bicycles Stack Exchange is a question and answer site for people who build and repair bicycles, people who train cycling, or commute on bicycles. It's 100% free, no registration required.

In the US, we're in the middle of a heat wave. Temperatures are topping 100 degrees F and up in some areas. When touring, how should one's eating and drinking before and during a ride be changed to deal with heat like this?

If I don't chicken out, I'll be touring this weekend. I've ridden in temperatures like this before, but I'd like to make sure I'm not missing anything obvious.

The usual way I deal with heat is to drink lots of water, eat properly, reapply sunscreen more often, and don't ride too hard; conserve energy and take a break during the hottest part of the day. (Noon to three, in my experience.) I keep my helmet padding wet, and make sure to eat salty food. However, I'm not sure if I should eat and drink the same kinds of things.

For during-the-ride food, I've packed dried fruit, nuts, trail mix, energy bars, and I have five water bottles that I keep topped off.

I'll have a camping load - around 40 pounds of stuff - and I usually keep a pace of around 10mph.

This ride will be mostly on the roads, in the Pine Barrens of New Jersey, so there won't be all that much climbing.

Specifically:

  • Do I stick with protein the night before the ride and carbs after, or does the heat bring different requirements to the table? I'm a vegetarian when away from home, so that restricts what I can eat for my lunch breaks.

  • In the past, I've eschewed sports drinks, but is important that I ingest electrolytes? Should I start looking into sports drinks?

share|improve this question
    
Most answers on this topic will deal more with what not to eat, and on maintaining hydration, proper clothing, etc... Are you looking specifically for food answers? Or could we edit to say something like "How do I prepare for cycling in unusually high temperatures?". I didn't just edit it because if you are looking for food specific answers, not overall diet or preparation, then I would be changing your intent. –  zenbike Jul 22 '11 at 9:58
    
I've found that foods that are particularly salty or spicy do not go down well in the heat -- you don't really feel like eating them, and they often leave you with a troubled stomach afterwards. And sport drinks often seem too "strong" in the heat -- many people like to water them down about 2:1. You do need to ingest more than the usual amount of salt, though, in the form of salty food, sport drinks, or salt tablets. Having a variety of road foods to choose from is a good idea, since you can't really predict what will appeal to you and what will sit well on your stomach. –  Daniel R Hicks Jul 22 '11 at 11:26
2  
And force yourself to apply the sunscreen in the morning, before you start, at least on the critical areas like the back of the neck. Once you get going you'll find you don't want to stop to do it. –  Daniel R Hicks Jul 22 '11 at 11:28
1  
@zenbike - I'm specifically looking for information specific to food and drink. A more general question would be... well, it would be a different question. –  Neil Fein Jul 22 '11 at 13:57
    
@Neil Fein: I thought it might be. That's why I asked... –  zenbike Jul 22 '11 at 16:04
show 1 more comment

3 Answers 3

up vote 6 down vote accepted

It is extremely important that you eat and drink properly when cycling in extremes of temperature.

In Dubai, where riding in the summer means riding regularly in 50c temperatures, this is a major problem.

Eating is less of a concern than hydration, but you want to avoid dehydrators, like alcohol, in your food. You also want to watch what spices and additives are present in your food, like high salt content, but your standard diet as noted (High protein the night before, and carbs after a ride and assuming unsalted nuts and trail mix) should be fine to ensure energy. (Too much salt in one go can upset the stomach by drawing water into the gut, especially if you're already dehydrated. So it needs to be in small doses.)

Avoid sugary drinks, stick mainly with water, and electrolyte replacement drinks with low sugar content.

Desert survival expert Marjorie Woodruff recommends drinking a few ounces of water every 1o minutes if water is limited, and a minimum of 1 liter every 45 minutes if water is readily available. Electrolyte replacement s fairly essential, but can be accomplished far more inexpensively using a product like Elete Water because it can be carried easily, and a very small container is an effective add in to about 25 liters of water. It's mostly tasteless, but in our experience here in Dubai, very useful.

Proper clothing is essential. Cover your skin. Do not rely solely on sunscreens, as they do not prevent dehydration, although they are better than nothing. Better yet, do both.

Another essential in hot weather cycling, especially while touring, and deadly essential if touring unsupported is the ability to recognize and understand what is happening when you are affected by heat, and what it feels like.

This article from the Mayo Clinic has a pretty thorough examination of exercise in hot weather, and what the dangers and effect are.

How to avoid heat-related illnesses

When you exercise in hot weather, keep these precautions in mind:

Watch the temperature. Pay attention to weather forecasts and heat alerts. Know what the temperature is expected to be for the duration of your planned outdoor activity.

Get acclimated. If you're used to exercising indoors or in cooler weather, take it easy at first when you exercise in the heat. As your body adapts to the heat over the course of one to two weeks, gradually increase the length and intensity of your workouts.

Know your fitness level. If you're unfit or new to exercise, be extra cautious when working out in the heat. Your body may have a lower tolerance to the heat. Reduce your exercise intensity and take frequent breaks.

Drink plenty of fluids. Dehydration is a key factor in heat illness. Help your body sweat and cool down by staying well hydrated with water.

Don't wait until you're thirsty to drink. If you plan to exercise intensely or for longer than one hour, consider a sports drink instead of water.

Sports drinks can replace the sodium, chloride and potassium you lose through sweating. Avoid alcoholic drinks because they can actually promote fluid loss.

Dress appropriately. Lightweight, loosefitting clothing helps sweat evaporate and keeps you cooler. Avoid dark colors, which can absorb heat. If possible, wear a light-colored, wide-brimmed hat.

Avoid midday sun. Exercise in the morning or evening, when it's likely to be cooler outdoors.

If possible, exercise in shady areas — or do a water workout in a pool.

Wear sunscreen. A sunburn decreases your body's ability to cool itself.

Have a backup plan. If you're concerned about the heat or humidity, stay indoors. Work out at the gym, walk laps inside the mall or climb stairs inside an air-conditioned building. Understand your medical risks. Certain medical conditions or medications can increase your risk of a heat-related illness. If you plan to exercise in the heat, talk to your doctor about precautions.

Heat-related illnesses are largely preventable.

By taking some basic precautions, your exercise routine doesn't have to be sidelined when the heat is on.

share|improve this answer
    
Is high salt content a dehydrator? I thought that it's necessary to have salt in order to retain water: if you drink water and don't have enough salt, then you'd just pee the water out again; lack of salt makes you hypovolemic. –  ChrisW Jul 22 '11 at 10:48
1  
No, salt isn't a dehydrator, and anyone who works in the heat needs additional salt. But too much salt in one go can upset the stomach by drawing water into the gut, especially if you're already dehydrated. So it needs to be in small doses. –  Daniel R Hicks Jul 22 '11 at 11:31
    
Thanks, @Daniel R Hicks. That's what I was getting at, but you said it way better than I did. I've edited my answer to include that information. –  zenbike Jul 22 '11 at 12:54
    
@ChrisW, I wasn't trying to say no salt, just not excessive salt. –  zenbike Jul 22 '11 at 12:57
    
Yes it's clearer now. When I have salt it tends to be indoors (I'm only commuting, not touring), with plenty of water to drink immediately and afterwards. –  ChrisW Jul 22 '11 at 13:02
show 2 more comments

Dehydration is probably your biggest worry in the heat. Checking the colour of your urine is one way to tell if you're becoming dehydrated.

colour chart

Fresh fruit contains water so would be preferable to dried fruit, but obviously it's less convenient to transport.

I have used sports drinks when running (specifically Lucozade Sport) and I find it helps, but that may just be psychological. Some sports drinks contain significant amounts of caffeine, I would avoid those as large doses of caffeine can have a diuretic effect.

Edit: This article in the British Medical Journal describes the limitations in using urine colour to assess hydration.

Bottom line: urine colour as a measure of hydration

General public—Evidence is lacking to suggest that urine colour is a useful, safe, or accurate marker of hydration

Professional athletes—Limited evidence to show that first morning urine colour can be reliably used to assess dehydration and rehydration

share|improve this answer
4  
Urine color is not always reliable. If you've ingested some sort of diuretic (or perhaps have an infection that's generating toxins the body wants to get rid of) then your urine output will be excessive and relatively clear, even though you may be dehydrated. And if you eat certain foods or take certain vitamins (particularly B vitamins) your urine may be quite yellow or orange even though you're over-hydrated. –  Daniel R Hicks Jul 22 '11 at 12:13
    
Good point, urine colour can be affected by other things. –  Tom77 Jul 22 '11 at 14:39
    
Still a good rule of thumb, though. –  Neil Fein Jul 22 '11 at 16:05
add comment

You need to use an electrolyte drink. This is exactly what they are made for. They help keep your body chemistry right for handling water. Sweat out too much of your salts and you won't be able to process the water properly.

Simplest is to drink Gatorade. It has electrolytes and carbs, both of which you will need.

Many cyclists use powders that you mix with water. For traveling, there are electrolyte tablets that are easier to carry and dissolve in water.

I ride with one bottle of energy drink and the second bottle of water. The water is good since you can also cool yourself by poring it on your head/back.

As far as food, various carbs are good, but try to include some protein. The Clif bars have protein and are vegan.

You might go to a cycling shop and see what the guys there suggest, there are tons of options designed for this.

Good luck and have fun!

share|improve this answer
    
Absolutely disagree. Sports drinks have their place, but for long distances in extreme heat, you want water. Drinking sports drinks ties your carbohydrate / electrolyte consumption to your hydration. You generally want to average no more than two servings of carbohydrates (equivalent to two bottles of sports drinks) per hour for longer rides, but in hot temperatures you may easily exceed three bottles of water per hour. –  Stephen Touset Jul 20 '12 at 14:05
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.