Exercising In the Heat
With Temperatures s in Dallas, Texas , and around the country, right now between 100 and 105 we have something even more serious to think about;
Heat Indexes between 105 and 107 degrees and Heat Related Illness.
Although a common myth about losing weight in the summer is the old adage; “Just Sweat it Out”, this is not only untrue, it can have negative health implications.
It is true, that we do lose weight while exercising in the extreme heat, it’s water weight, and with the human body, being made up of between 70-80% water, losing too much is just dangerous.
Losing 1-3% of your body weight during an activity can actually decrease your performance up to 10%.
So staying hydrated before, during and after, an event or race is essential for not only your performance but your health.
Here’s what’s to look out for if you are exercising in the heat.
There are two types of heat exhaustion:
- Water depletion. Signs include excessive thirst, weakness, headache, and loss of consciousness.
- Salt depletion. Signs include nausea and vomiting, frequent, muscle cramps, and dizziness
Heat Exhaustion Signs and Symptoms:
- Confusion
- Dark-colored urine (a sign of dehydration)
- Dizziness
- Fainting
- Fatigue
- Headache
- Muscle cramps
- Nausea
- Pale skin
- Profuse sweating
- Rapid heartbeat
Heat Stroke Signs and Symptoms:
The signature symptom of heat stroke is a core body temperature above 105 degrees Fahrenheit. But fainting may be the first sign.
- Throbbing headache
- Dizziness and light-headedness
- Lack of sweating despite the heat
- Red, hot, and dry skin
- Muscle weakness or cramps
- Nausea and vomiting
- Rapid heartbeat, which may be either strong or weak
- Rapid, shallow breathing
- Behavioral changes such as confusion, disorientation, or staggering
- Seizures
- Unconsciousness
When we exercise in the heat we experience something called, Cardiac Drift. The cardiovascular system is already working harder in the heat, with your heart working 5-10 beats harder per minute than at the same intensity on a cooler day.
There are some suggestions that I recommend while riding. The main goal is to avoid heat related illness, and the best way to avoid heat illness, is to keep the internal body temperature cool.
The single best advice I can provide is to ride in the coolest part of the day, the morning. The coolest part of the day is day break, the time when the sun is just breaking the horizon. We need someone to clear the spider webs off the trail, why not let it be you? 🙂
But not everyone has the gusto to get rolling at such an early hour, nor does their scheduled allow. So here are some other suggestions to help prevent heat related illness.
Shade: For Mountain Bikers choosing trails that are in trees, that provide shade, with the best option being a trail that is not only shaded but allows for a breeze.
Water: Drink Plenty of water before, during and after a ride. The 1st DORBA Fall Race is scheduled on August 18th. For Zoefitness Clients who are prone to cramping, and eat a diet high in processed foods, and therefore sodium, I generally recommend that they buy a gallon of water 3 days out and drink it in it’s entirety on that day. I do this for a couple of reason. The number one reason is to bring up their hydration status, so that the athlete is hydrated for the race and this gives the athlete plenty of time to excrete any excess water before race day.
Making sure you’re hydrated before a race or ride is one of the best preventative tools we can utilize to our advantage. A general guideline for exercise is 16-20 ounces of water about 2 hours before implementing a training session or race. This will give your body time to remove any excess water from your system. And 4-6 ounces about 15 minutes prior starting.
It’s recommended to drink about 4 ounces of water every 15 minutes. This is the rule of thumb I follow, and generally recommend, but I know athletes who consume closer to 8 ounces every 15 minutes during exercise. The amount of water that you will need to consume, is based on your sweat rate. If you’re a heavy sweater than, it’s likely you will need more water then the recommended 4 ounces.
A good and simple guideline to follow is: “a bottle(20 oz) an hour”.
For every 1 pound weight loss during a ride = 16 ounces of water post ride:
so if you lose 3 pounds you should consume 48 ounces of water to replace what has been lost.
Sweat is not only water but it is also made up of electrolytes, and minerals. So it’s imperative that you replace those as well. Failing to do so can lead to a condition known as hyponatremia, and can be deadly. Bob Seebohar, one of my mentors, recommends getting upwards to 800 mg of sodium an hour. This would turn me into a raisin. As a general rule of thumb, if you are heavy salt sweater, you will have salt or whitish streaks, where you sweat the heaviest. Salt is not the only mineral we lose in sweat.
I recommend Salt Stick Capsules. This is my favorite product and has been for years. It’s the only product that I know that contains all of the electrolyte/minerals: Calcium, Magnesium, Chloride, Sodium and Potassium. It also contains, the magic ingredient, Vitamin D3, which aids in the recycling of ATP.
Sports Drinks may or may not be a necessity. They are an excellent way to replace some of your electrolytes, and are a great tool for replacing carbohydrates during activities lasting longer than an hour.
Cooling vests, and cooling shirts have extensive research supporting their success in cooling the body temperature. Here are a couple of other ideas to help keep the body cool: Freeze a water bottle and place this in the back jersey pocket of your shirt. Freeze your hydration pack about 1/3 to 1/2 full, and make sure you have cold water in a cooler in your car/truck so you can enjoy cold water in between laps, and when you’re finished.
Take Breaks, I take shade breaks, both when I ride on and off road. Sometimes I will actually stop to allow my body temperature to decrease, but more frequently I will slow my speed, and do a track stand, for a few moments.
Go Slower in the heat. Since the heat raises your HR considerably, we just have to slow our speed down a little bit, we are going slower at the same heart rate on a cooler day. You’re still working hard, at least your heart is, so sometimes, it’s okay just to slow your speed down to avoid a trip to the ER.
Ride in the morning, evening, or indoors on rollers or a trainer. Rollers and stationary trainers are good in the winter but they’re also very good for the summer, when it gets dangerously hot, especially if you are not a morning person.
Use the Buddy System: If you’re riding by yourself, use what I call a “contact person”. I call one of my buddies, and ask them to be my contact person. I tell them, what time I am starting, where I will be riding, what my itinerary for riding is, and what time I should finish. I let them know what time I will call them, and I give them a time, to call the brigades if they haven’t heard from me. So far to this date, I have never needed my contact person in an emergency, but the best thing we can do is plan, and not need it, then to need it, and not plan.
Carry a phone: you want to always carry a phone, or have at least one phone in your group. This way you can call your contact person and let them know you’re going to ride another lap, have a flat, or in the case of an emergency; you, or even a perfect stranger may have one, that you can assist with.
Listen to your body: All of the time, not just in the heat. If you have your internal regulators on you can tell when you’re over doing it, when the heat is getting to you, when you need a shade break, or when you just need to finish your ride. If you’re on a one way trail and start to feel the onset of something serious, turn it around, and get off the trail, or finish the ride as soon as possible. Don’t worry that you’re going the wrong direction. Just get yourself safe.
Once you get to your car, enjoy some ice cold water, and blast the air condition, and don’t worry about driving until your core temperature is back to normal!