The temperatures are rising, which can drive some people to the comfort of an air-conditioned gym. Hesitant to exercise outdoors? Don’t sweat it — there are a number of ways to beat the heat and get a great workout without hiding in the gym (or at home!) all summer long.
It’s Getting Hot in Here — The Need-to-Know
Short of removing all of one’s clothing, Nelly might have been on to something. Exercising in high heat and humidity intensifies how hard the body needs to work to maintain normal function. During workouts, core temperature naturally rises, but this can happen far more quickly on a hot day. The body’s response is to turn on the sweat glands and circulate more blood to the skin in order to cool it down (clothing optional). As the workout continues, the heart pumps faster to send blood to muscles and to the skin Control of skin circulation during exercise and heat stress. Roberts, M.F., Wenger, C.B. Medicine and Science in Sports. 1979 Spring;11(1):36-41.
Summer means sweat, and all that perspiration means one thing: potential dehydration. The hotter the temperature, the more risk for dehydration, especially during an intense workout. Dehydration can actually affect the brain, impairing short-term memory and the ability to estimate fatigue, meaning the brain can think the body isn’t working as hard as it actually is — a dangerous state to be in when temperatures are high Effects of fluid ingestion on cognitive function after heat stress or exercise-induced dehydration. Cian, C., Barraud, P.A., Melin, B., et al. Centre de Recherches du Service de Santé des Armées, Unités de Psychologie et de Bioénergétique et Environment, France. International Journal of Psychophisiology. 2001 Nov;42(3):243-51.
High core temperature, increased heart rate, and dehydration create a perfect storm that could turn into one of three heat-related illnesses: heat cramps, heat exhaustion, or — the most serious — heatstroke. Warning signs include muscle cramps, nausea, and dizziness, but by taking the proper precautions, a summer workout can be a breeze.
Be Cool — Your Action Plan
There are plenty of ways to avoid the scary stuff. Here are six things any one can do to (literally) beat the heat.
1. Hydrate: The number one, Grade-A, most important thing to do is hydrate. Then hydrate again. And then hydrate some more! Loading the body with hydrating fluids before an exercise can help summer athletes work out longer before the risk of dehydration sets in. But what to drink and when? One study specifically recommends drinking plenty of fluid two hours before exercise, five to 10 ounces of fluid every 15 minutes during exercise, and fluids with increased sodium content after exercise Keeping sports participants safe in hot weather. Sparling, P.B., Millard-Stafford, M. Department of Health & Performance Sciences, Georgia Institute of Technology. The Physician and Sportsmedicine. 1999 Jul;27(7):27-34. Exercising in the heat can also sweat out sodium and electrolytes, which are both useful for athletic performance Hydration and sweating responses to hot-weather football competition. Kurdak, S.S., Shirreffs, S.M., Maughan, R.J., et al. Department of Physiology, Cukurova University, Turkey. Scandinavian Journal of Medicine & Science in Sports. 2010 Oct;20 Suppl 3:133-9 Dehydration and rehydration in competitive sport. Maughan, R.J., Shirreffs, S.M. School of Sport, Loughborough University, U.K. Scandinavian Journal of Medicine and Science in Sports. 2010 Oct;20 Suppl 3:40-7. Just be careful not to overhydrate, which can be just as dangerous as dehydration Consequences of overhydration and the need for dry weight assessment. Raimann, J., Liu, L., Ulloa, D., et al. Renal Research Institute, U.S.A. Contributions to Nephrology, 2008;161:99-107.
2. Drink Something Cold: On a hot day it’s better to drink something cold before exercising as a way to preemptively cool the body down. In one study, male cyclists drank either a cold or a warm beverage 30 minutes before a workout. Those that drank the cold beverage were able to pedal longer, had lower skin temperatures, and had lower heart rates than those that drank a warm beverage Cold drink ingestion improves exercise endurance capacity in the heat. Lee, J.K., Shirreffs, S.M., Maughan, R.J. School of Sports & Exercise Sciences, Loughborough University, Leicestershire, United Kingdom. Medicine and Science in Sports and Exercise. 2008 Sep;40(9):1637-44. Bonus points: Having a cold drink before a workout is much more practical (and money smart) than other precooling strategies, like taking ice baths Keeping your cool: possible mechanisms for enhanced exercise performance in the heat with internal cooling methods. Siegel, R., Laursen, P.B. School of Exercise, Biomedical and Health Sciences, Edith Cowan University, Australia. Sports Medicine. 2012 Feb 1;42(2):89-98.
3. Electrolytes: It’s also important to replenish electrolytes, lost through sweat, during warm weather workouts Exercise in the heat: strategies to minimize the adverse effects on performance. Terrados, N., Maughan, R.J. Fundacion Deportiva Municipal, Sabino Alvarez Jendin, Aviles, Spain. Journal of Sports Sciences. 1995 Summer;13 Spec No: S55-6. Electrolytes, such as sodium and potassium, help the body retain and absorb water. Most sports drinks provide a good amount of electrolytes, and electrolyte powders are also available to amp up regular water. Use caution though — many sports drinks contain extra sugar and other additives, which add up to unnecessary calories.
Good thing sports drinks aren’t the only way to get those much-needed electrolytes! One study compared the effects of rehydrating with water, mineral water, Gatorade, and a mixture of apple juice and water. The only beverage that showed any difference in restoring electrolytes after exercise in the heat was the apple juice-water drink — those that drank it retained more potassium than the others Rehydration after exercise in the heat: a comparison of 4 commonly used drinks. Shirreffs, S.M., Aragon-Vargas, L.F., Keil, M., et al. Sport and Exercises Sciences Facility, Loughborough University, UK. International Journal of Sport Nutrition and Exercise Metabolism. 2007 Jun;17(3):244-58. (Potential apple juice bonus: Potassium also helps prevent muscle cramps.) The study used a small sample, so make sure to try out whatever fluids give the best personal results.
4. Carbo-Loading: Electrolytes aren’t the only things to stock up on: The body also needs more carbohydrates during intense workouts in the heat. Carbo-loading is a good idea for an endurance event. Try making carbs about 50 to 55 percent of your total calories about a week before, then ramping up to about 70 percent in the days just before the event. Smaller athletes should aim for 4.5 grams of carbs per pound of bodyweight (3.5 for larger athletes such as, say, weightlifters). One study recommends chugging sports drinks when a workout will last longer than an hour because the carbs will provide more energy to power through in the stretch Nutritional needs for exercise in the heat. Burke, L.M. Department of Sports Nutrition, Australian Institute of Sport, Bruce, Australia. Comparative biochemistry and Physiology: Part A, Molecular and Integrative Physiology. 2001 Apr;128(4):735-48.
5. Climate: Acclimatization to the heat is also important when preparing for summer workouts. Gradually increase the intensity and duration of outdoor workouts in the heat so the body can better adjust and adapt to the conditions. Proper acclimatization can result in better sweat response, lowered heart rate, and lowered body temperature Acclimatization strategies—preparing for exercise in the heat. Shapiro, Y., Moran, D., Epstein, Y. Heller Institute of Medical Research, Sheba Medical Center, Tel Hashomer, Israel. International Journal of Sports Medicine. 1998 Jun;19 Suppl 2:S161-3. The process can take up to 10 to 14 days, but it’s important to ease into the new regime during the first few days for best results Preseason heat-acclimatization guidelines for secondary school athletics. Casa, D.J., Csillan, D., et al. Journal of Athletic Training. 2009 May-Jun;44(3):332-3.
6. Morning People: Another pro tip is to exercise in the morning. It may seem obvious, since outdoor temperatures are lower early in the day, but our body temperatures are also lower in the AM than in the afternoon Different effects of heat exposure upon exercise performance in the morning and afternoon. Racinais, S. Research and Education Centre, Qatar Orthopaedic Sports Medicine Hospital, Doha, Qatar. Scandinavian Journal of Medicine and Science in Sports. 2010 Oct;20 Suppl 3:80-9 Exercise capacity in the heat is greater in the morning than in the evening in man. Hobson, R.M., Clapp, E.L., Watson, P., et al. School of Sport and Exercise Sciences, Loughborough University, Loughborough, United Kingdom. Medicine and Science in Sports and Exercise. 2009 Jan;41(1):174-80. When the alarm goes off, try to throw on some light-colored clothing. It reflects light, which will help keep the body cooler than dark colors, which absorb light. And night owls, relax: becoming a morning person isn’t so hard.
Follow these tips, and it should be a piece of cake to rock a summertime workout. Need a bigger incentive to step away from the gym? There’s a special bonus to successfully training in the heat: things could be easier when temperatures drop. A study showed that the effects of proper heat acclimatization — improved sweat response, lowered heart rate, and lowered body temperature — stay with an athlete even when training in cooler temperatures Heat acclimation improves cutaneous vascular function and sweating in trained cyclists. Lorenzo, S., Minson, C.T. Department of Human Physiology, University of Oregon, Eugene, OR. Journal of Applied Physiology. 2010 Dec;109(6):1736-43. Now those are details worth sweating over!
How do you beat the heat and stay active during the summer? Is it best to just stay inside? Share your thoughts in the comments below.