Exercising outdoors, especially during summer months, may be a wonderful and pleasant experience, but it certainly comes with challenges. Even the most physically and cardiovascularly fit must exercise (pun intended) caution and understand the importance of safety measures.

Heat Index in Dry Climates vs Humid Climates

For those that live in regions with dry climates, temperature and the sun’s heat are the main concern, as these determine the heat index. Even in the drier climates, when the temperature reaches 80 degrees, the National Weather Service (NWS) advises caution when exercising outdoors. For example, if the humidity is very low at 25% and the temperature is 85 degrees fahrenheit, the heat index is 82, which is considered to be in the “caution” zone by the NWS. If the humidity is a little more moderate at 40%, and the same temperature of 85 degrees, the heat index rises to 90, which pushes this temperature/humidity combo into the “extreme caution” zone.

In regions with higher humidity, the moisture combined with sun and warm temperature drives the heat index up even more dramatically. When comparing the same 85 degree temperature with a humidity level of 70%, the heat index is 95, which is considered the “extreme caution” zone. With humidity at 90% and temperature of 85 degrees, the heat index rises to a whopping 105 and is in the “danger zone”! Humidity levels clearly have a profound effect on the heat index, but we must also be mindful that the sun and higher temperatures are also factors to be considered when training and engaging in strenuous exercise outdoors. It is highly advisable to exercise early in the morning (or later in the evening) while the sun is low in the sky, and to reduce the intensity levels when working out in summer heat and humidity. 1

Importance of Hydration

With higher temperatures, it’s important to note that the body utilizes more energy to keep from overheating; thus, you lose fluids much more rapidly than when temperatures are lower. And when humidity levels are high, we lose more fluids at an even quicker rate, which increases the risk of heat exhaustion and heatstroke.

Warning signs of heat exhaustion:

*Muscle cramps




If you have any of these symptoms, immediately stop exercising and get to an air-conditioned room or a shady spot and sip cool water. If possible, lie down with your feet slightly elevated and dab a cool cloth over your face and use a fan to keep cooler air circulating on you, and rest to help your body temperature come down. If symptoms persist and body temperature doesn’t cool down within 30-60 minutes, go to a doctor or emergency room to avoid further complications and the possibility of heatstroke, which can damage vital organs and possibly cause death.

Sweating is how the body keeps cool, but this is primarily how most fluid is lost. It’s critical to be well hydrated before, during and after your workout. Simple guidelines to prevent dehydration: drink between 16-20 oz purified water 2 hours prior to outdoor workouts, drink 8 oz every 15 minutes during the workout, and drink another 16-20 oz post workout.


In addition to water, electrolytes are critical for ample hydration, as well as many other critical functions in the body (this will be discussed in a future blog post). The 4 main electrolytes that need to be replenished from exercise are: Sodium, Potassium, Magnesium and Chloride. I highly recommend supplementing with electrolytes to ensure your body has the proper electrolyte balance as well as keeping your body well hydrated, particularly during the summer months. Designs for Health makes a wonderful product, Electrolyte Synergy, to help replace the electrolytes lost due to exercise. This product also includes Vitamin C & Taurine (to help support the cardiovascular system), Quercetin, Rutin, and Citrus Bioflavinoids (polyphenols/plant extracts for additional fluid balance support).  Recommended dosage is 2 teaspoons in 12 oz of water before exercise.


As a courtesy during July & August, I’m offering 10% off the purchase of Electrolyte Synergy by Designs for Health:

Purchase at Deeper Health Supplement Store

(1st time purchasers please enter Registration Code VF1430 to set up new account)

Enter coupon code HCPC1430WELCOME for 10% off order (for both new & repeat purchasers)



Remember the Rules & Tools

So if you’re heading outside for a run, group interval class, cycling, or other outdoor exercise, be sure to exercise early morning or in the evening when the sun is lower, reduce your intensity level and duration, hydrate pre, during and post workout, and include Electrolyte Synergy to give your body the extra support it needs during the hot summer months.  As they say in Italy, lunga vita estate (long live summertime)!