It’s getting hot out there! Are you prepared? Dealing with the heat requires a proactive approach rather than a reactive one. For hot weather training and racing, it’s essential that you anticipate the effects of the hot environment and prepare a specific hydration and body cooling strategy.
Sweat evaporation is the most important cooling mechanism your body has, responsible for 80% of body cooling.* That means hydration is crucial to keeping the body cool. Did you know that being just 2% below optimal body water can result in up to 11% reduction in max power?* Our bodies can only tolerate a 1 to 2% drop in body water before dramatically decreasing athletic performance.
How can you keep your body hydrated, cool and performing well in hot weather? Think about what you have control over and take action. Here are a few tips to beat the heat:
If you know it’s going to be a hot week of training or racing, prepare ahead of time by consciously hydrating with plain water and electrolyte beverage at least two days leading up to the event. Set yourself up for success by heading into a race/ride with a surplus of fluids rather than a deficit.
While the weather may not be in your control, the amount of bottles you carry is. Bring extra water bottles and ice even if you don’t think you’ll need it. Carry an extra bottle in your jersey pocket and always stop to top off water bottles at water spigots.
If you’re thirsty, chances are you’re already dehydrated. Unlike bonking, it is very difficult for your body to come back from even mild dehydration.
In hot weather, aim to drink 2 to 3 bottles per hour of electrolyte beverage and water. You can stay on top of hydration by sipping at least 8.5 ounces or one third to half of the fluid in your bottle every 15 minutes.
Drinking plain water alone is not ideal in hot conditions because your body needs sodium to help water reach cells. Electrolyte mixes can help offset the electrolytes lost in sweating and also help prevent hyponatremia. Find an electrolyte mix that works well for your and bring extra with you on rides to refill bottles mid-way through. A few brands to consider are Amped Hydrate, Skratch Labs, or Osmo Nutrition.
Light colored kits, short sleeves/sleeveless and shorts are best for hot weather riding. For heat to leave the skin, the skin needs to be exposed. Clothing traps hot air, so the less the better.
It takes 10 to 12 days for your body to acclimatize to hot environments.* When first exposing yourself to hot temperatures, avoid peak heat hours and instead ride in the early morning or late afternoon when the temperatures are cooler. You may also want to back off on intensity as your body acclimates to the hot environment. After about 10 or 12 days, your body will adapt and sweating will begin earlier and become more watery (reducing sodium loss), sweat rate will increase, blood plasma volume will increase, your body will use less glycogen meaning you won’t fatigue as quickly, and your heart rate will reduce.
A quick way to cool down your core temperature is to immerse your body in cool water. Before a hot race or ride, douse your entire body in cold water. The water left on your hair and skin will continue to evaporate and cool you down without requiring sweat water loss. You can also find a calm lake or stream to create the same effect before, during and after activity.
When it comes to race day, always prepare for the worst and hope for the best. Don’t assume you will get a feed or neutral water on a race course. Always bring as much water as you can carry. The extra weight is always worth it. It’s also wise to have a designated ice water bottle for spraying your body down to keep cool during the race.
If you have an opportunity to get a feed or water bottle, always take the water even if you don’t think you’ll need it. Your teammate or another rider may need it, or you can use the bottle to spray down your body or save for emergencies.
Recovery starts before, during and after you ride. Replacing water you’ve lost during exercise long after the workout is over will help you recover more quickly. Remember to keep drinking electrolytes to replace the minerals you’ve depleted.
How much fluid should you replace? Try this simple trick:
Weigh yourself naked before activity, weigh yourself naked immediately after exercise. Subtract your after-exercise value from your before-exercise value. The difference in weight represents the loss of fluid. 1 pound of fluid is 16 ounces. For example: 160 lbs (before) – 157 lbs (after) = 3 lbs of fluid lost = 48 ounces of fluid that need to be replaced.
Race Day Tips:
Warning! Watch for Signs of Dehydration & Heat Injury
Don’t ignore the warning signs of dehydration and heat injury. It is never advisable to sacrifice your safety to finish a race or training ride. See below for the three stages of heat injury, warning signs and suggested treatment.
Heat injury has three stages:
Stage 1: Heat Cramps, Dizziness & Nausea
Treatment: Stop riding, find a cool shady spot to sit, drink cool fluids and electrolytes as soon as possible, stretch, and if dizzy lie down. You should recover after cooling the body down and hydrating sufficiently.
Stage 2: Heat Exhaustion
If you push past cramps and ignore nausea or dizziness, things can get severe. Symptoms of heat exhaustion include: headache, nausea, cold clammy skin, pale complexion, collapsing from dizziness, weak rapid pulse, shallow breathing. Your body’s sweating mechanism will begin to shut down due to extreme loss of fluid.
Treatment: Call 911 immediately. Heat exhaustion is very dangerous and needs immediate medical attention. You may need fluids administered intravenously.
Stage 3: Heat Stroke
At this point, the person has collapsed completely. Symptoms include very high body temperature, dry skin, unresponsiveness, labored breathing.
Treatment: Call 911. Immediate treatment is necessary. Immerse the person in ice to cool them down.
Be prepared, ride smart, and keep that power up in hot weather!
Kinesiology, Part II Exercise Physiology. Dr. Stephen Glass, PhD, FACSM; Brian Hatzel, PhD, AT, ATC; Rick Albrecht, Phd.
OsmoNutrition.com. Dr.Stacy Sims