Heat Acclimation

It’s still winter where I live, but if you’re planning on running early spring or summer races, preparing for running in the heat should be on your mind. There are lots of changes that occur in your body when you become adapted to the heat during exercise.

One of the first things is you have a lower heart rate when exercising at a particular temperature. Your blood plasma increases, which allows you to move warm blood toward the outside of your body to dissipate heat. Increased blood plasma also allows you to begin sweating earlier and at a higher rate. Sweating earlier means your body will start sweating when your core temperature goes up by one degree rather than two or three. This head start may not seem like much, but is important for maintaining a lower core temperature.

Without the increase in your plasma volume, you would compromise your cardiovascular output as more energy was shunted to decreasing your body temperature through sweat and moving your blood around.

Now keep in mind that just because you are more efficient at running in the heat, does not mean that you can slack off on your hydration. You are actually losing more fluid because you are sweating earlier and at an increased rate. The change in the amount of sweat lost can be huge. Normal fluid lost for one hour of exercise is 0.5 to 1 liter. As you become heat acclimated, this can increase up to 1-2 liters per hour.

How do you get ready for the heat? run in the heat. hot and humid is difficult to adapt to but you can do it to a point. If it’s winter or just not hot enough where you live, there are still some things you can do. The bottom line is you want to increase your core body temperature to about 100 to 101.5 degrees.

Some options include building a really simple heat chamber in your home, over dressing. If you have the space, create a room that gets really hot. You can use space heaters or stop the clothes dryer from ventilating outside (which will increase humidity too). Ideally, you’ll have a treadmill, but some other type of exercise equipment like a stationary bike or elliptical machine will be all right.

Over dressing is pretty simple. Just put on lots of extra clothing and then go running. In doors is going to be the best, but out doors will work if you don’t have another option. This isn’t an ideal way to prepare but it is better than nothing.

Another, less effective, way is to do some high intensity exercise until your core body temperature is up to 100-101.5 and then go sit in the hot tub or a sauna.

Adapting to the heat takes about seven to fourteen days of heat exposure for one hundred minutes a day. You can do a much shorter period of three to five days and it will help you feel better when running in the heat, but for endurance events the longer period is what you should be doing.

The problem is that heat training makes you tired, so you don’t want to do this super close to your race date, but you have to balance that with not losing the heat adaptation you’ve tortured yourself to develop. Try to complete your heat training 3-4 days before your event.

 

Is your sunscreen working?

Everyone knows there is a risk of developing skin cancers by exposing unprotected skin to the sun and that risk increases depending on how long you’re in the sun and when. Where you live also increases or decreases your risk.
Factors such as time of day latitude, altitude, and time of year change the amount of UV’s you’re exposed too. The EPA’s sunwise app predicts UV levels based on these factors. Other personal risk factors include, facial cleansers, fair skin, blue eyes, red hair, and freckles.
Every year companies review the Effectiveness of and harm caused by sunscreens. Prior to 2014, there were no regulations on sunscreen effectiveness, ingredients, or claims of preventing skin cancers.
In 2011, after 4 years of multiple articles being published about the harmful ingredients and lack of actual protection, standards were created by the FDA. In 2014, testing standards were implemented. Although, the US standards are lower than Europe’s. Now in the US, companies can no longer use the claim that their sunscreen “prevents skin cancers.”
Ongoing air pollution has increased our risk of skin cancers. Cases have increased by 35% over the last 30 years. The FDA also, now, requires sunscreen to screen both  UVA and UVB rays. But about half of products do not screen them equally and they could not be sold in Europe.
Most sunscreen companies have stopped putting a harmful type of vitamin A, retinyl palmitate, in its product. This ingredient may increase the speed of developing melanoma. However, consumers should still check for it-14% contained it in 2017.
Higher SPF claims do not mean more screening. SPF over 50 is misleading and does not mean more protection. Most countries cap the SPF claim at 50. The FDA is drafting a regulation to address this issue.
Nor are the claims of sweatproof, waterproof, or sunblock entirely accurate and thus no longer allowed to be printed on the screens. A skin cancer warning is required.
Spray on sunscreen are not as effective as creams/lotions. They don’t go on evenly or thick enough. There is a danger of inhalation as well.
Sunscreens need to be reapplied every two hours and sunscreen is not enough. If you’re going to be in the sun for long periods of time or between 10 am and 4 pm wear UV protective clothing, a hat and sunglasses.
Indoor tanning is also a big no-no. It increases your risk of all types of skin cancer including melanoma, which is the most dangerous. It’s illegal for someone under the age of 18 to use indoor tanning beds in most countries, including the US. It’s like smoking when you know the risks for cancer and other health problems. You are actually more likely to get skin cancer from indoor tanning than you are lung cancer from smoking (although it may cause other serious health/lung issues).
Best sun screen list here.

Heat Related Illness

heat stroke

Temperatures are climbing here in the western United States and that means coping with the heat and preventing heat stroke and heat exhaustion. Heat stroke is a serious condition, which can damage and kill brain cells by causing the body’s temperature to rise to a core temperature of 105 degrees Fahrenheit. It can also cause death.

Symptoms of heat stroke include dizziness, throbbing headache, red hot and dry skin, no sweating, muscle cramps, nausea and vomiting, rapid heartbeat, shallow breathing, confusion, disorientation or staggering, seizures, and unconsciousness.

If you suspect someone has heat stroke, you must cool them down as quickly as possible. You can do this by getting them out of the sun, putting ice on their neck, armpits, and groin area, fanning them with water while wetting their skin.

Heat related illness is related to the heat index, which is how hot you feel when the effects of the air temperature and humidity are combined. Higher humidity makes you feel hotter because it hinders your body’s ability to cool itself through sweating. Also being in full sun can increase the heat index by 15 degrees. Some people are more prone to heat stroke than others, such as, people over the age of sixty-five and under four, athletes, people with a chronic disease, someone who is dehydrated or consuming alcohol, sleep deprivation, and people on particular medications (check with your doctor to see if your medication lowers heat tolerance).

Everyone is different when it comes to heat sensitivity. A sudden change in temperature without adequate time for the body to acclimatize increases the risk for heat related illness. There is not a certain temperature when heat related illness becomes a possibility, but the more factors that are present the more aware you need to be to look for symptoms.

To reduce your risk of getting heat stroke or heat exhaustion wear loose fitting light colored clothing, wear a light weight hat with a large brim or that also covers your neck, wear sun screen (sun burn increases the risk of heat stroke), hydrate, and take electrolytes.

heat stroke prevention

For those of us who will be running in the heat you can increase your heat tolerance by running in the heat. Make sure and take the above precautions before you go out to heat train. Take water with you on your run, start small with three miles, and then increase a little bit at a time. If you start to get show signs, seek some shade and try again another day.

If you do get heat stroke, you are more prone to getting it again at least for the next few months because of the damage to your cooling system and because whatever caused you to get it in the first place is likely still present.

 

I’m too Hot! I’m too Cold! I’m just right.

I’m a list writer. So, as I’m preparing for the Salt Flats 100, I have written lists for everything. My friends and family believe I over think things, and that I’m pretty much crazy, but it helps me prepare and maintain my sanity as race day gets closer. I draw the line at making lists of my lists. At that point, I will have myself committed to the State Hospital.

 Salt Flats is in the middle of nowhere, as are many 100-mile races, it’s not as if you can just run to the store and pick up a forgotten item. I have a list of what goes in each drop bag. I have a list of what I need to give to my crew. I have a list of things my crew needs to address at each aid station. I have a shopping list. I have a list of clothing to pack.

Springtime weather in Utah can be unpredictable. It can go from 75 degrees Fahrenheit and sunny to 30 degrees Fahrenheit and hailing in a matter of minutes. Knowing this, my list of clothing has nearly every piece of running attire I own on it. To complicate matters, I place the same items in multiple drop bags such as long sleeve shirts and pants. But you have a crew, why doesn’t your crew just carry it all? Because any number of things could go wrong with my crew, and I need to know my gear is where I need it to be even if my crew isn’t. My crew will come into an aid station and pick up my drop bag, so it is ready for me. If they are not there, for whatever reason, I know my stuff is there waiting for me.

Knowing what to wear at various temperatures comes with experience. Everyone’s heat and cold tolerance is different. It’s all about layers (Like an onion? Yes, like an onion).   Continue reading