How to acclimate to hot weather

If you spend most of your time this summer in the air-conditioned confines of your home, car, and workplace, when you go outdoors you may feel as if you have stepped into a blast furnace.

Acclimatization is the process by which you become physically adjusted to the temperature of your environment. It plays an important role in how well you tolerate heat and cold.

Outdoor acclimatization

People who spend a great deal of time outdoors become “outdoor acclimatized.” These persons are affected less by heat or cold extremes because their bodies have adjusted to the outdoor environments.

Acclimatization usually occurs over a period of about two weeks in healthy, normal persons. This process is faster in response to heat, but slower in the cold.

Factors affecting climate acclimatization

Your physical condition, age, and other factors also affect how your body copes with heat and cold.

Body fat

Lean people tolerate heat better than obese people. The more obese a person is, the less skin surface area the person has in relation to his or her weight. Greater surface area provides more exposed skin to perspire and cool the body through evaporation.

But this same fat can be beneficial to a person who lives in cold climates because the fat insulates skin tissue. The Inuit, who live in cold regions, tend to have more body fat than people who live in warmer climates.

Elderly persons usually don’t tolerate temperature extremes as well as do younger people. As a person ages, the body’s response to temperature change–shivering in low temperatures and sweating in high temperatures–is delayed and reduced.


Some medications may interfere with the body’s ability to tolerate temperature extremes because they affect parts of the brain responsible for temperature regulation. For example, some asthma and hay fever medications can reduce your tolerance to heat or cold.

Metabolic rate

A person’s metabolic rate–the speed at which the body’s cells turn food into energy–affects the person’s ability to cope with heat and cold. A relatively high metabolic rate produces more heat than a relatively low metabolic rate. As a result someone with a high metabolic rate may feel warm in a room of 72 degrees where a person with a low rate may feel cool.

Prepare to cope with the heat

You may be better prepared to cope with the summer heat if the temperature of your indoor environment does not differ radically from the temperature outdoors. Setting the air conditioning temperature 10 degrees below the outdoor temperature is suggested.

Acclimatization is the beneficial physiological adaptations that occur during repeated exposure to a hot environment. These physiological adaptations include:

  • Increased sweating efficiency (earlier onset of sweating, greater sweat production, and reduced electrolyte loss in sweat).
  • Stabilization of the circulation.
  • The ability to perform work with lower core temperature and heart rate.
  • Increased skin blood flow at a given core temperature.

To acclimatize workers, gradually increase their exposure time in hot environmental conditions over a 7-14 day period. New workers will need more time to acclimatize than workers who have already had some exposure.

Acclimatization schedule

  • For new workers, the schedule should be no more than a 20% exposure on day 1 and an increase of no more than 20% on each additional day.
  • For workers who have had previous experience with the job, the acclimatization regimen should be no more than a 50% exposure on day 1, 60% on day 2, 80% on day 3, and 100% on day 4.

In addition, the level of acclimatization each worker reaches is relative to the initial level of physical fitness and the total heat stress experienced by the individual.

Maintaining acclimatization

Workers can maintain their acclimatization even if they are away from the job for a few days, such as when they go home for the weekend. However, if they are absent for a week or more then there may be a significant loss in the beneficial adaptations leading to an increased likelihood of heat-related illness and a need to gradually reacclimate to the hot environment.

Spicy days are here, here’s how to acclimate to heat and get an edge on your competitors.

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Often, as spring progresses toward summer, runners warn me that they won’t do well because they aren’t good at running in heat.

My answer is always the same. “You’re going to have to prove that.” I then tell them of a trainee who, after accepting that challenge, shattered her 5K PR in an 87°F road race. Admittedly, it was an evening race, with a lot of shade. But what really made the difference was that she’d taken time to acclimate.

One way to do this is simply by embracing the heat as the days warm from 65°F to 70°F, 75°F, and beyond. Don’t hide from it by running at dawn, but use it to make yourself gradually more heat tolerant. In my PR years, I would wind up running in late afternoon, with the sun not only hitting me, but reflecting back at me from white-painted buildings that flanked one of my favorite running routes. Hot? What’s that? I loved it. Especially because pretty much everyone else was melting.

That’s one way to adjust.

But if needed, you can do it a lot more quickly, says Lawrence Armstrong, a heat researcher at the University of Connecticut. Only a few days of focused heat acclimatization, he says, can produce an amazing array of physiological adaptations, all designed to make your body sweat more efficiently.

How to acclimate to hot weather

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Increase Your Sweat Reservoir

One is that your plasma volume increases. This may increase your weight by a couple of pounds, but don’t worry about it: that’s an extra liter of fluid your body is able to sweat away without dehydrating. “You have a greater reservoir to work with,” Armstrong says.

At the same time, your sweat becomes less salty, conserving sodium. That is useful, says Matt Harber of Ball State University, Muncie, Indiana, because conserving sodium helps you maintain proper fluid balance, even as you sweat.

You also start to sweat more profusely, and earlier on in the workout.

That used to be seen as a sign of being out of shape, says Yannick Molgat-Seon, an exercise physiologist at the University of Winnipeg, Manitoba. “But it’s actually a good thing,” he says — an indicator that your body is anticipating what’s soon to come and taking preemptive measures to deal with it. Harber agrees. “Better sweaters are in better shape,” he says.

Optimize Heat Output

Another change is that your body diverts more blood to the skin.

That has two effects: One is that it allows sweat glands to increase their output. But when you are running, 75-80% of the energy expended by your muscles winds up as heat, and the more easily your blood can carry this heat to the skin where your sweat can eliminate it, the less there is to accumulate in your muscles.

Pump More Blood

Finally, your heart rate during exercise lowers.

On first blush, that doesn’t sound like a good thing — after all, you want as much blood as possible circulating to your muscles (for running) and your skin (for cooling). But it turns out that slowing the heart rate at any given exertion level allows the heart to fill more completely between beats. That actually allows it to pump more blood per minute, not less.

Daniel Lieberman, the evolutionary biologist and exercise researcher of “Born to Run” fame, thinks these adaptations are holdovers from our distant past. Early humans, he says, came from the African savannas where they evolved to hunt and forage in midday heat, when it was too hot for less heat-tolerant predators.

We no longer have to avoid becoming lunch to a lion, but deep in our DNA, he suggests, we retain the genes that allowed our ancestors to survive. All we need to do is to reawaken them when needed.

How to acclimate to hot weather

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10 Days from Heat Wimp to Heat Champ

I once lived in Texas, and have visited it several times. It’s a place where summer heat can set in with a vengeance, as though someone flipped a switch, and one rule of thumb I picked up from the local runners is that it takes about 10 days of running in heat to adjust.

Brett Ely, a 2:38 marathoner who is now an assistant professor of exercise science at Salem State University, Massachusetts, agrees. She once helped the Army develop a protocol for training soldiers for deployment to Iraq, where temperatures can exceed 110°F. Eight to 14 days, she says, is all you need.

Nor do you need to spend extended amounts of time each day in heat. All the way back in 1963, a research team led by someone named A.R. Lind found that there was no advantage to extending heat-training workouts beyond 100 minutes. An hour is probably good enough.

Heat-training workouts don’t even need to be all that hard. In a 1991 paper in Sports Medicine , Armstrong found that all that’s really needed is to run at something more than 50% of VO2max — basically an easy jog.

I myself have found that you can assist the process by measures unrelated to running, such as being sparing in your use of air conditioning, especially in your car. Sitting in traffic with the windows down and the air conditioning off isn’t the same as running intervals on the track, but heat is heat, and if you can get comfortable doing that, it will help.

You also don’t need to bake yourself every day. My runner took two months to adapt for her PR at 87°F, and another old study , this one by someone named J.T. Fein, bears her out. Training once every three days for a month, Fein found, is every bit as effective as training daily for ten days. What seems to matter is getting in about 10 heat-training sessions, overall — just as my Texan friends taught me, all those years ago.


There are, of course, caveats.

Be aware of the symptoms of potentially dangerous overheating. A sudden sensation of feeling chilled, even though it’s hot, is a red-flag warning to “stop now.” You should also check to make sure you’ve not stopped sweating, an even stronger warning of incipient heatstroke. Nausea on a hot day is another sign you may have crossed into the danger zone.

“Start gradually,” Ely says. “If you were going to high altitude, you wouldn’t do a hard workout on the first day. You’d ease into it.”

But, don’t just write off summer as too hot. Embrace the heat (cautiously) and see what surprises might lurk in your ancient savanna-hunter genes.

Heat-related illness poses a serious health risk to farmworkers, especially as their work season overlaps with hot summer temperatures. The two types of serious heat illnesses, heat exhaustion and heat stroke, can cause permanent damage to the body or even result in death. On average, approximately five crop workers die from heat illness annually in the US; this is 20 times higher than for all workers.

Workers are at higher risk of heat-related illness if they are not acclimated (or used to) the heat. Cal/OSHA reports that at least half of reported incidences of heat illness and deaths were in unacclimatized workers. Almost half of the reported cases were on the worker’s first day on the job, and 80% were within the first four days.

How to Acclimate to the Heat

To function properly, the body needs to stay between 97 and 99°F. The body adjusts to help maintain this body temperature regardless of what the temperature is outside. The process that helps a person adjust to the heat is called acclimatization. In acclimatized workers, the body cools down faster by sweating more efficiently (i.e., sweating earlier and losing fewer electrolytes through sweat).

It can take up to two weeks for workers to acclimate to the heat. For those two weeks while the body is adjusting to the hotter temperatures, workers are at a higher risk of developing heat illness. It is important that everyone takes extra precautions while acclimating to the heat.

The California Heat Illness Prevention Study (CHIPS) found that while 86% of workers had received training on heat illness prevention within the previous year, only 42% correctly answered a question testing knowledge of acclimatization.

What to do:

  • Train workers on early signs and symptoms of heat illness. Emphasize the dangers of working in the heat while unacclimatized, particularly for new workers, at the start of the heat season, and before a heat wave. Be sure to review the key concepts by asking workers questions to ensure their understanding.
  • Gradually increase exposure to heat over one to two weeks.
    • For new workers, start with 1.5–2 hours of work on their first day, and increase by 1.5–2 hours each day.
    • For experienced workers or workers coming back from a break of a week or more, start with a half day’s work on their first day, and then add 1.5–2 hours each day.
    • Rest more frequently in shade.
    • Work at a slower pace.
    • Drink more water.


    Given the importance of training and increasing knowledge, WCAHS has developed discussion guides to help employers communicate the Cal/OSHA heat standard to their employees. In addition, WCAHS offers Heat Illness Prevention trainings for supervisors.

    How to acclimate to hot weather

    When you think about racing in hot environments you may think of summer. While summer can certainly be hot in several locations, it’s often fall and spring racing that brings more trouble because athletes are traveling to warmer environments for events.

    Whether you travel for racing or not, you may find yourself concerned with acclimation to heat and humidity. Consider the following situations:

    • You train in cool fall air and your next race is in a hot environment.
    • You train in cool spring air and the first race of the season is in a hot city.
    • You live in a city that is always cool relative to the locations where you race.
    • You live in a hot, dry environment but plan to travel to a hot, humid environment for a race.
    • You live and work in an air conditioned environment but race in a hot and humid environment.

    Most, if not all, endurance athletes have encountered the negative effects of heat on race results. Why is it that some athletes seem to handle hot conditions better than others and can anything be done to help you train for the heat?

    Body Temperature

    Your body regulates internal temperature within a relatively narrow range. Most people consider a normal oral temperature to be 98.6 degrees Fahrenheit, though there can be normal variations of 1 degree or more.

    When internal temperature rises, your body works to cool down. At low levels of heat stress, your body is able to manage the load. As the heat load increases, you are at risk for heat cramps, heat exhaustion and the most serious condition of heat stroke.

    Heat stroke occurs when your core temperature exceeds 105 degrees Fahrenheit. If not addressed, heat stroke can result in death.

    Body Cooling

    Your body regulates temperature through radiation, conduction, convection and evaporation. When your body is warmer than the environment, it radiates heat into the environment. Radiation does not require molecular contact between objects. The easiest way to experience radiant energy is when your body absorbs radiant energy from direct sunlight or reflection from snow, even in freezing conditions.

    Conduction involves a transfer of energy from one molecule to another though a liquid, solid or gas. Conductive body cooling depends on the temperature difference between the skin and surrounding surfaces and the thermal qualities of those surfaces. For example, water is more conductive than air. You can sit motionless and comfortably much longer in a 75-degree-Fahrenheit room than you can in motionless water at the same temperature. This is because water has the ability to absorb heat several thousand times faster than air.

    Convection is the heat exchange associated with moving air or water adjacent to the body. Back to the 75-degree example in the last paragraph, if you add a fan to move air past you while sitting in the room, you will feel cooler. If you are stationary in 75-degree water that is moving, you will feel much cooler than if the water was motionless.

    The final, and most critical, body defense to overheating is evaporation. The evaporation of sweat from the surface of your body, the changing of a liquid to a gas, cools your skin. It is important to note that it is not sweat, per se, that cools your body; rather it is the evaporation of sweat from your skin that cools the body.

    The relative humidity of the air surrounding your body is the most important factor that determines the effectiveness of evaporative cooling.

    F all is here, and the mercury is falling in thermostats across the northern hemisphere. The good news: Not only will your body acclimate to the cooler weather, but you can also hurry this process along.

    Beginning in the 1960s, U.S. Army researchers found that nude men who spent eight hours a day in a 50°F (10°C) chamber became habituated to the cold and had mostly stopped shivering after two weeks. Later research from Scandinavian and U.K. teams likewise concluded that people can get used to cool environments. And a recent research review from Army researchers concluded that all humans seem to have at least some ability to acclimatize to the cold.

    A small 2014 study published in the journal PLOS One, a group of healthy men spent up to three hours a day sitting in baths filled with 57°F (about 14°C) water. (That’s roughly the temperature of the Atlantic Ocean along the New Jersey and New York coastlines in late October, according to the National Oceanic and Atmospheric Administration.)

    At the start of the 20-day study, the men did a lot of shivering, which is the human body’s initial response to cold. Their heart rates and metabolisms sped up, generating heat. At the same time, their blood vessels narrowed and drew back from the surface of the skin, causing skin temperature to drop. Basically, the men’s vascular systems clenched—pulling blood toward their warmer interiors in an effort to escape the exterior cold.

    But by Day 20, much had changed. The men’s shivering had more or less stopped. While their metabolisms and heart rates still sped up in response to the cold-water bath, their blood vessels no longer constricted and their skin temperature didn’t drop the way it had before. The men reported less discomfort during their chilly baths. At the same time, their blood samples contained fewer markers of cold-induced stress and immune-system activity. It appeared their bodies had gotten used to the chill.

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    The changes your body goes through in cold weather

    “Everyone has an ability, to some extent, to acclimatize to cold,” says Marius Brazaitis, first author of the study and a senior researcher at Lithuanian Sports University. He says the human body seems to achieve acclimatization through a mix of different internal adjustments, which people can either encourage or suppress depending on their behaviors.

    What sorts of internal adjustments? There’s evidence that a particular type of fatty tissue, known as “brown fat,” may help the body generate heat in response to persistently cold conditions. “Chronic cold exposure somehow activates brown fat, which we know undergoes dramatic seasonal changes,” says Shingo Kajimura, a professor in the Department of Cell and Tissue Biology at the University of California, San Francisco.

    Kajimura says newborns have a lot of brown fat, which helps them stay warm because they lack sufficient muscle to shiver. While it was once thought that people lost their stores of brown fat as they grew out of infancy, research has found that parts of the adult body—specifically, the area around the upper spine and neck—either retain brown fat or generate new brown-fat tissues in response to cold.

    The placement of this brown fat is important. Kajimura says that temperature perception is monitored by the brain, which detects the cold in part by noting the temperature of blood flowing into it through the neck. “That’s why putting a scarf on makes you feel warm,” he says. By warming the neck and the blood flowing through it, a scarf “tricks” the brain into believing it’s warm—just as a cold cloth on the neck can help the brain cool off in summer. It’s possible that, in response to regular cold exposure, brown fat in the neck area both forms and becomes more active, keeping us more comfortable at colder temperatures.

    Brazaitis says the human body seems to possess a number of different mechanisms that help it adjust to the cold. But most people in the developed world suppress these adaptive mechanisms, at least to an extent, by shielding their bodies from “thermal distress.”

    “Putting on more clothes, drinking more hot drinks, increasing room temperature, consuming more food, which increases inner metabolic rate—this behavior does not allow [the body] to become more resistant to cold,” he says.

    While they may impede the body’s ability to adjust to colder temps, pulling on a sweater or sipping some hot tea does little long-term harm. But cranking up the thermostat in your car or home costs money. Home and vehicle heating is also a major contributor to greenhouse gas emissions, according to the U.S. Environmental Protection Agency. By encouraging your body to adapt to the cold, you can feel comfortable during the fall and winter without needing to entirely rely on heating system.

    Adjusting your thermostat down by a few degrees, shedding layers, and spending more time outside in cold conditions—basically, anything that causes you to shiver—will help your body acclimate to the cold, Brazaitis says. If you can induce shivering a few times a day, you’ll begin to feel more comfortable in colder temps after just one week, he says.

    The quickest way to adapt to the cold

    If you really want to accelerate your body’s habituation to the cold, frigid showers will get the job done. “Cold showers are no fun, but they cause the body to adapt pretty quickly,” says John Castellani, a research physiologist for the U.S. Army who has studied how people respond and adapt to the cold. He suggests starting off with just a quick cold-shower exposure—say 15 seconds—and adding 10 seconds every day. (You can turn up the water temp once you’ve endured your measure of icy water.)

    Spending time in a cold shower or in other cold environments is safe for most—and may even confer some health benefits. But people at risk for heart trouble need to be cautious. “The first thing that happens when you’re exposed to cold is your blood vessels constrict and blood pressure goes up,” Castellani says. And so exposure to the cold—especially extreme cold, like jumping in an icy lake—can trigger a heart attack or other problem in people who have heart disease, he says.

    But if your heart’s healthy and you’re looking to harness your body’s natural ability to adapt to the cold, a week of shivering—and maybe a few cold showers—should do the trick.

    After months of cold weather running, the summer heat and humidity feel like a shock to the system. When you are out running, they literally are. Your cardiovascular system works harder to pump enough blood to the skin to keep you cool. Faster rates of fluid loss can affect muscle function. Overheating can send a signal to your brain to shut down the run. Each year, no matter how many years you have been running, you need to adjust your training for running in heat and humidity as part of the acclimatization process.

    Training adjustments to heat and humidity will vary widely based on the individual runner. Your current fitness, personal preference and tolerance for hot weather, and geographic location will all impact how much you need to adjust your training at the start of summer. High humidity also requires acclimation; if you live in a humid area, your training may require more adjustment than if you train in an arid region. There is a reason many elites train in Flagstaff, not the Midwest!

    Some runners may barely need to adjust, especially if summer temperatures gradually increase. Others may need to allow longer to adjust, especially if the weather suddenly changes from 45-degree mornings to 70-degree mornings.

    Temporarily adjusting your training will not harm your fall racing goals. If anything, a focus on long-term, sustainable growth will only benefit you in fall races – and beyond.

    Hydration becomes of the utmost importance during summer running. Always hydrate before and after runs and carry water even on short runs. Do not forget about electrolytes!

    Treat the Heat and Humidity as a Training Stress

    It is vital to understand heat and humidity as a type of training stress, just like mileage and intensity. Training does not take place within a vacuum. Heat and humidity make running objectively harder, particularly before you are acclimated for the season.

    Too much stress hinders adaptation, increases injury risk, and multiples the likelihood of mental burnout. You do not want to increase multiple training stresses at the same time. Your long-term training will improve if you allow yourself time to adapt to the stress of the heat, before increasing mileage or intensity.

    As you acclimate to summer weather, consider keeping other aspects of your training load the same. The first few weeks of summer may not be the ideal time to increase mileage or start a speed segment. You may even choose to slightly decrease volume or intensity as you acclimate.

    Train for Time, Not Distance

    Almost all runners will slow down during the acclimation period, if not during the entire summer. Any run will naturally take longer. If you are limited on time or tempted to push the effort to finish at your normal pace, consider running for time instead of distance. An hour easy run is an hour easy run, whether you run it at a 10:00 min/mile in 70-degree heat or a 9:00/mile in 40-degree temperatures.

    When in Doubt, Run Easy

    Many runners possess a tendency to go too hard, too often. When heat and humidity spike, this tendency becomes even more detrimental to adaptation. Running too hard too often when unacclimated to the heat will apply too much training stress. Too much stress hinders adaptation and creates a vicious cycle of subpar runs and performance plateaus.

    An easy run is always beneficial, no matter what your goals are. Want to run faster? Easy runs will improve your running economy. Want to run farther? Easy runs build endurance. If you struggle with heat and humidity, just focus on easy mileage for a few weeks as you adapt.

    If you struggle with controlling your effort in the heat and humidity, consider training with heart rate. Heat and humidity will spike your heart rate, so you will likely run much slower to maintain an aerobic heart rate zone – but in summer, easier is better.

    Modify Your Quality Workouts

    If you are well adapted to quality workouts such as tempo runs, intervals, and the like, you can likely continue them during summer. However, you may want to modify the format and scale the intensity as you acclimate. This post details exactly how to modify a speed workout for summer. Opt for shorter intervals and fartlek-style workouts, hill repeats, and leg speed development runs (such as these summer speed workouts). Take your focus completely off of pace, because your paces will be slower to reflect the higher energy demands of running hard in the heat. Your perceived effort is what matters!

    Know When to Bail a Run

    There are circumstances that warrant quitting a run, especially in summer. Extreme heat and humidity can be dangerous, especially if you are not acclimated. If you stop sweating, experience lightheadedness or dizziness, or your form noticeably deteriorates, stop running. Those extra miles have no training benefit at that point and the risk of heat stroke or hyponatremia is high.

    Maximize your performance in hot temperatures with our heat running secrets

    The heat is the most difficult element for runners to train in.

    The effects of heat and humidity on training and racing are two- fold and impact performance both long-term and short-term.

    During a workout or a race in the heat, your performance suffers for three different reasons.

    In this guide, we’ll help you understand why running in the heat is so hard, learn how to adjust your workouts and races properly, and how to maximize your performance.

    Why running in the heat is hard

    First, you have an increase in your overall body temperature. Just like when you run a fever, the higher your core body temperature, the worse you are going to feel.

    Second, as soon as the body starts to heat up, blood is diverted to the skin, where cooling takes place through sweating and evaporation. Therefore, less blood is available to transport oxygen to the working muscles. Less oxygen means you can’t run as fast or as hard and the effort to maintain or increase your pace dramatically increases. In this way, training and racing in the heat is somewhat similar to altitude training.

    Finally, you become more easily dehydrated in hot and humid conditions. When fluid levels drop, your body’s cooling methods, mainly the ability to sweat, erode and you have a harder time controlling your body temperature. This in turn causes the core body temperature to rise faster, which creates a viscous cycle that severely limits performance.

    How running in the heat effects recovery

    Not only does heat and humidity make that one specific workout harder, it also hampers recovery and your ability to perform on subsequent workouts.

    After you exercise in hot conditions, your body needs to spend more energy on cooling itself rather than delivering nutrients to your battered muscles.

    When the muscles can’t get the nutrients they need to repair the damage caused by the workout, recovery is slower and you may not be fully prepared for your next hard workout like you normally would be.

    Running in the Heat Trick #1 – Adjust Your Paces

    As we can clearly see, performance suffers in the heat and humidity. I’ve worked with some runners who question the amount the heat and humidity actually affects their workout and race times, but it’s a scientific fact that even the most heat acclimatized runner will suffer performance loss in hot conditions.

    Therefore, it’s important that you find ways to adjust your workout times and race paces to reflect how you’ll perform in hot conditions. Likewise, sometimes you need to know how much more effort a workout is taking in hot and humid conditions so you can better monitor fitness and progression.

    How to adjust your running pace in the heat

    Luckily for you, I’ve created calculator that will estimate of how much harder you’re working in the heat and humidity. Download your calculator on how heat effects your running times here.

    Running in the Heat Trick #2 – Proper Hydration

    Hydration is a critical element to staying cool and performing your best in hot conditions.

    What makes hydrating so difficult is knowing exactly how much fluid you need to stay cool and replenish what you lose through sweating.

    Likewise, pre-hydrating and re-hydrating with the proper fluids is critical to maintaining fluid levels and performing at your best

    Every runners sweats at a different rate relative to their conditioning, acclimatization, and individual make-up. A study conducted by Jack Daniels found that runners with similar backgrounds, training regimens and under identical training conditions differed in sweat loss by as much as 2.5 liters per hour.

    This means that while I may only sweat at a rate of 1.5 liters per hour, you might sweat at rate of 4.0 liters per hour, making drinking and hydrating much more important for you.

    How to measure sweat loss in the heat

    To help you out, I’ve created a simple calculator that will enable you to calculate your exact rate of fluid loss at given temperatures so that you know exactly how much you need to rehydrate before, during, and after a run of any distance or temperature.

    You can use our sweat loss calculator here.

    Sports drinks vs. Water

    The critical factor in hydration is how rapidly fluids can be absorbed into the blood stream. As a general rule, the higher the carbohydrate content, the slower the absorption rate.

    Therefore, you should drink water of diluted sports drinks before and during running and sports drinks or a recovery beverage after.

    Here’s a more in-depth analysis of sports drinks or water for runners.

    How to hydrate before a run

    Research has demonstrated that beginning your run hyper-hydrated (of hydrating your body above its normal state before exercise ) will delay or eliminate the onset of dehydration, particularly if you fail to completely replace sweat loss during your run.

    The problem is that you will quickly urinate any excess fluids. Luckily, we have a simple trick using a product called glycerol that will help you retain this extra fluid and increase your performance by up to 6% in hot and humid conditions. Check out our article on hydrating before your run

    Running in the Heat Trick #3 – Racing in the Heat

    The heat is the most difficult element for runners to compete in and race well. As mentioned previously, with the rise in core body temperature, a runner will have less oxygen available to working muscles, become dehydrated, and suffer a decline in performance.

    However, we do have a few tricks up our sleeves to teach you how to race better in the heat.

    Pre-cooling before a race

    Pre-cooling is a technique used to slightly lower a runner’s core body temperature before they start running, which in turn extends the amount of time they can run hard before hitting that critical temperature threshold. Learn how you can use pre-cooling to improve your racing times.

    Racing a Marathon in the heat

    Running a marathon or half marathon in the heat isn’t an exciting thought. However, you can’t change the weather, so the best strategy is to be prepared. The following is a brief list of some innovative strategies and tips that you can implement on race day should you have to run a marathon in the heat

    Structured Workouts automatically sync with compatible devices and guide you through workouts in real time.


    Pav Bryan – Amazon #1 Author + BikesEtc Magazines ‘Cycling Guru’ & ‘King Of Endurance’


    Structured Workouts automatically sync with compatible devices and guide you through workouts in real time.

    Plan Description

    This plan has been designed by Pav Bryan ( – Amazon #1 New Release Author, BikesEtc Magazines ‘Cycling Guru’ and ‘King of Endurance’.

    Has the temperature recently changed outdoors or do you want to get outdoors to train, but suffer in the heat? Do you consider yourself to be a ‘highly trained’ athlete, where 500 TSS points per week is the minimum you train at? This plan is for you! This is to compliment your existing regime not to replace. Add this to your current program. It is part of the wider; Hot Weather Package, brought to you by DPC.

    Purchase this plan and get a 20% discount voucher for use off a Spruzza device, the perfect accompaniment to any Hot Weather Plan!

    PLEASE NOTE: that while all features listed below still work, some of the links in the sessions might not and some of the newer TrainingPeaks features are unavailable. This plan has been updated and can be found in the TP store (email if you can’t find it). There is a guide attached to day one of this plan which contains a user guide including new links to resources such as blogs and videos.

    We will be looking to gradually adapt your body to the heat you have outdoors, this will require some form of ‘on-the-bike’ cooling, we recommend the Spruzza device for this. It is a five week long plan. It is important to add this to your existing training and not to replace anything.

    This plan will ask you to ride outdoors in the heat, a smaller training loop is more ideal for this so you can be close to somewhere to cool off. If you begin to feel ill during any of the acclimation sessions, slow down or stop.

    This plan is the most comprehensive and user-friendly plan on the market! Only plans from Direct Power Coaching come with support. We win when you do so buy this plan and will support you by providing you a free guide to download in day one and if you do have any questions you can email [email protected] and we will respond within 48 hours.

    You can use any method to monitor your training, power, heart rate or rate of perceived exertion, although power is an advantage. You get key rides to ensure you are capable across every aspect of cycling; nutrition, hydration, technique, tactics and of course performance. Truly personal coaching without the expense of working with a coach 1:1.

    95% of the sessions you will do come with comprehensive instructions, links to videos, blogs or downloads, plus they have the workout builder function and can be directly uploaded to Garmin too complete!