Good old H2O is critical for rehydrating when the body experiences fluid loss, such as when we sweat. Water, Hydration and Health. Popkin, B.M., D’Anci, K.E., Rosenberg, I.H. et al. Department of Nutrition, University of North Carolina, Chapel Hill, NC. Nutrition Review, 2010 August; 68(8):439-458. Even though many gyms like to keep pricey sports drinks and protein shakes stocked on their shelves, most of the time, water will do the trick just fine. Shoot to sip seven to 10 ounces of fluid every 10 to 20 minutes during exercise to stay properly hydrated. Fluids and hydration in prolonged endurance performance. Von Duvillard, S.P., Braun, W.A., Markofski, M., et al. Nutrition, 2004 Jul-Aug;20(7-8):651-6. If you’re working out for longer than an hour or doing a particularly intense exercise (like running a marathon or participating in a tough training session), you will probably need to replace electrolytes too—this is where a sports drink or electrolyte-enhanced water comes in handy. Cardiac biomarkers, electrolytes, and other analytes in collapsed marathon runners: implications for the evaluation of runners following competition. Siegel, A.J., Januzzi, J., Sluss, P., et al. Department of Medicine, McLean Hospital, Belmont, MA. American Journal of Clinical Pathology, 2008 Jun;129(6):948-51. However it’s also important to be wary of overhydration: Too much water can lead to hyponatremia, which is when excess water in our bodies dilutes the sodium content of our blood. Too much of a good thing? Whitfield, A. British Journal of General Practice, 2006 July 1; 56(528):542-545. Incidence and prevalence of hyponatremia. Upadhyay, A., Jaber, B.L., Madias, N.E. Department of Medicine, Tufts University School of Medicine, Boston, Massachusetts. American Journal of Medicine, 2006 Jul;119(7 Suppl 1):S30-5. "It is most often caused by long duration exercise and either drinking fluid at a rate that is more than fluid losses or only replacing fluid losses with hypotonic fluids like water," CamelBak hydration advisor, Doug Casa, says.
2. Sip on sports drinks and coconut water.
When we sweat, we lose electrolytes, which are minerals found in the blood that help to regulate (among other things) the amount of water in the body. Research suggests and sports drinks, such as Powerade and Gatorade, can help prolong exercise and rehydrate our bodies because they contain electrolytes, which plain old water does not. Anaerobic performance when rehydrating with water or commercially available sports drinks during prolonged exercise in the heat. Coso, J.D., Estevez, E., Baquero, R.A., et al. Universidad de Castilla-La Mancha, Toledo, Spain. Applied Physiology, Nutrition, and Metabolism, 2008 Apr;33(2):290-8. While an ordinary workout may not require electrolyte-replenishing, those participating in longer and more intense periods of exertion, such as running a marathon or going through a particularly intense workout, will benefit from a good dose of electrolytes mid-workout. Fluid and electrolyte balance in ultra-endurance sport. Rehrer, N.J. Shool of Physical Education and Department of Human Nutrition, Otago University, Dunedin, New Zealand. Sports Medicine, 2001;31(10):701-15. Not in to sports drinks, or want a more natural alternative? Water-enhancing electrolyte tablets, coconut water, or a homemade sports drink could be potentially effective substitutes. Comparison of coconut water and a carbohydrate-electrolyte sport drink on measures of hydration and physical performance in exercise-trained men. Kalman, D.S., Feldman, S., Krieger, D.R., et al. The University of Memphis, Cardiorespiratory/Metabolic Laboratory, Department of Health and Sport Sciences, Memphis, TN. Journal of the International Society of Sports Nutrition, 2012 Jan 18;9(1):1.
3. Turn to fruit.
Many fruits are a great source of both electrolytes and fluids, though the dose of electrolytes can differ from fruit to fruit. Carbohydrate and electrolyte contents in commercial fruit juices. Jirapinyo, P., Phosuya, P., Thammonsiri, N., et al. Department of Pediatrics, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand. Journal of the Medical Association of Thailand, 2001 Jul;84(7):942-7. Bananas and dates are known for having high levels of the electrolyte potassium, making them a great option for refueling during an intense workout (for example, a long run). Plasma Potassium Concentration and Content Changes After Banana Ingestion in Exercised Men. Miller, K.C. Department of Health, Nutrition, and Exercise Sciences, North Dakota State University. Journal of Athletic Training, 2012 Nov-Dec; 47(6): 648-654. To stay hydrated while keeping up electrolytes, it’s important to drink water while munching on fruit (fruit contains some water, but not as much as your water bottle).
4. Weigh yourself.
Hop on the scale before and after exercise. For each pound lost during activity, drink an additional 16 ounces of fluid. If your body weight change is three percent or more, you may be experiencing significant to serious dehydration. Urinary indices during dehydration, exercise, and rehydration. Armstrong, L.E., Soto, J.A., Hacker, F.T., et al. Human Performance Laboratory and Department of Physiology and Neurobiology, University of Connecticut, Storrs, CT. International Journal of Sports Nutrition, 1998 Dec;8(4):345-55. Losing a few pounds of body weight after exercise can put strain on the body and result in uncomfortable side effects like muscle cramps, dizziness, and fatigue. Dehydration. A.D.A.M. Medical Encyclopedia. Last reviewed: August 15, 2011. To prevent sweating away the water that keeps us hydrated, have a water bottle at the ready.
5. Check the toilet.
If you’re taking a mid-set break to hit the loo, check on the color of your urine to make sure you’re staying hydrated. When properly hydrated, urine should be pale yellow in color. Though it may be tricky to keep an eye on it, try to watch the urine stream, since the color of urine will dilute when it hits the toilet water. Store this handy, dandy urine color test in your phone or wallet to make sure your piddle is up to snuff—dark yellow urine may indicate dehydration. Dehydration. A.D.A.M. Medical Encyclopedia. Last reviewed: August 15, 2011.
6. Tame thirst.
Whatever you’re drinking, be it water, juice, or sports drinks, make sure to take a sip or two whenever you feel thirsty. Even if you’re not feeling totally parched, mild thirst is still a sign of impending dehydration.
7. Pay attention to your muscles.
Lean muscle tissue contains more than 75 percent water, so when the body is short on H2O, muscles are more easily fatigued. Effects of dehydration and rehydration on EMG changes during fatiguing contractions. Bigard, A.X., Sanchez, H., Claveyrolas, G. et al. Unite de Bioenergetique et Environment, Centre de Recherches du Service de Sante des Armees, La Tronche, France. Medicine and Science in Sports Exercise, 2001 Oct;33(10):1694-700. "Staying hydrated helps prevent the decline in performance (strength, power, aerobic capacity, anaerobic capacity) during exercise,"Casa says. When your muscles feel too tired to finish a workout, try drinking some water and resting for a bit before getting back at it.
8. Pinch yourself. (No, really.)
Go ahead, pinch yourself! Skin turgor, which is the skin’s ability to change shape and return to normal (or more simply put, it’s elasticity), is an easy way to check your hydration (though not 100 percent reliable for everyone). Is skin turgor reliable as a means of assessing hydration status in children? Fayomi, O., Maconochie, I., Body, R. St. Mary’s Hospital, London. Emergency Medicine Journal, 2007 rebruary; 24(2): 124-125. Skin-textile friction and skin elasticity in young and aged persons. Gerhardt, L.C., Lenz, A., Spencer, N.D., et al. Laboratory for Protection and Physiology, Empa, Swiss Federal Laboratories for Materials Testing and Research, St. Gallen, Switzerland. Skin Research and Technology, 2009 Aug;15(3):288-98. Chain gangs: new aspects of hyaluronan metabolism. Erickson, M., Stern, R. Department of Basic Biomedical Sciences, Touro College of Osteopathic Medicine, New York, NY. Biochemistry Research International, 2012;2012:893947. Using your pointer finger and thumb, simply pinch the skin on the back of your hand (not too hard!) and hold for a few seconds. When you let go, if the skin takes a while to return to its normal position, you may be dehydrated.
9. Keep dry mouth at bay.
One of the first signs of dehydration is dry mouth. If your mouth starts feeling like the Sahara, head to the water fountain (or take a sip from your reusable water bottle!). A short water break between sets or during quick breaks from cardio can help stave off exercise-induced dehydration. Acute effect of oral water intake during exercise on post-exercise hypotension. Endo, M.Y., Kajimoto, C., Yamada, M., et al. Department of Exercise Science and Physiology, School of Health and Nutritional Sciences, prefectural University of Hiroshima, Hiroshima, Japan. European Journal of clinical Nutrition, 2012 Nov;66(11):1208-13. Fluid replacement during exercise. Noakes, T.D. Exercise and Sport Science Reviews, 1993;21:297-330.
10. Stop if you get the dizzies.
Feeling lightheaded during a workout is a sign of dehydration and a signal to tone it down a notch. Dizziness. A.D.A.M. Medical Encyclopedia. Last reviewed: May 1, 2011. Though willpower sometimes makes us want to push ourselves through a few more reps or another mile, feeling dizzy is an indicator that it’s time to hydrate." Due to the decreased plasma volume with dehydration during exercise," Casa says, "the heart must work harder to get blood to the working muscles." When there’s not enough water in blood, both blood volume and blood pressure drop, resulting in dizziness. Neuropsychological Performance, Postural Stability, and Symptoms After Dehydration. Patel, A.V., Mihalik, J.P., Prentice, W.E., et al. University of North Carolina at Chapel Hill, Chapel Hill, NC. Journal of Athletic Training, 2007 Jan-Mar;42(1): 66-75.
Next time you plan for a sweat sesh, keep these tips in mind for a safe, hydrated workout.
Originally published January 2014. Updated July 2015.