by Jennifer Trimmier
Summer temperatures are already soaring well into the 90s and with the precedent of the past several summers looming over our heads, it’s time for a refresher in proper exercise hydration so that our bodies can survive and thrive in the infernal heat.
Exercising in higher temperatures puts additional stress on the body’s thermoregulatory system, which regulates body temperature (think sweat). Couple the heat with higher humidity in our region and exercisers are at a higher risk for dehydration and heat-related illnesses such as heat edema (temporary swelling of the hands/feet/ankles), heat cramps, heat exhaustion and heat stroke. In addition to acclimating to the rising temperatures by reducing exercise intensity and taking breaks often, exercisers should hydrate well before, during and after exercise to prevent heat-related illness.
The American College of Sports Medicine (ACSM) and the United States Track and Field Association (USATF) developed the following fluid-intake guidelines:
- Two hours prior to exercise, drink 17-20 ounces
- Every 10-20 minutes during exercise, drink 7-10 ounces (more for excessive sweating)
- Following exercise, drink 16-24 ounces for every pound lost
Optimal exercise hydration also consists of following general fluid-intake guidelines on a daily basis so that the body is never in a state of dehydration. The Mayo Clinic recommends the following guidelines:
- For men, approximately 100 ounces or 13 (8-ounce) cups per day
- For women, approximately 75 ounces or nine (8-ounce) cups per day
Note that these amounts are more than the traditional notion to drink eight 8-ounce glasses of water a day. Per the Mayo Clinic, drinks consisting mostly of water (i.e. milk, juice, coffee, tea) count toward your goal as long as caffeinated or alcoholic beverages don’t count for the majority of your intake.
Many exercisers wonder whether they should consume sports drinks to replace lost nutrients during sweaty workout sessions. For most people, water is the best defense at fending off dehydration and heat illness while exercising outdoors during the summer. According to the American Council on Exercise (ACE), there is usually no need for sports drinks containing additional electrolytes, sodium or carbohydrates unless the exercise session lasts more than two hours.
Symptoms to Watch For
Recognizing and responding to the signs of dehydration is the best way to prevent individuals from suffering from more serious heat illnesses. The main symptom of dehydration, and one of the most under-recognized, is the feeling of thirst. An exerciser should drink when he or she is thirsty even when fluid-intake amounts are higher than the guidelines listed above.
Severely dehydrated athletes can have impaired performance, uncoordinated movement, muscular weakness and may experience heat syncope, which is sudden dizziness while exercising in the heat. If you notice these symptoms, try to get the affected person to a shaded area, give him or her fluids and place cool towels on the person’s body.
Medications and certain medical conditions can also affect water loss and fluid-intake needs. Check with your health care provider if you have questions about specific conditions or medications.
Jennifer Trimmier is an ACE-certified personal trainer who owns Strong Body San Antonio Fitness & Wellness Coaching. She provides at-home and on-location personal training and wellness coaching for individuals and groups. To learn more, visit www.StrongBodySA.com or call 210-445-0448.