Living and exercising in the southeastern U.S. for the last 35 years has made me acutely aware of the effects that heat and humidity can have on athletic performance. Pickleball courts on average are 15-20 degrees Fahrenheit hotter than the air temperature. Dehydration is a chief concern in such conditions. It can harm your health as well as your playing performance.

Simply defined, dehydration occurs when you lose more fluid than you take in. Water makes up about 60% of body weight and is involved in almost every process essential for life. Even a slight fluid imbalance can cause serious health concerns because water is needed to cool the body and aid in energy production. Water is also the basis for all bodily fluids, including blood and digestive juices. It is involved in the absorption of nutrients and waste elimination.

During pickleball, water is lost through sweating and breathing. Playing in high temperatures and humidity can cause fluid losses of up to 2.5 quarts (2.4 liters) per hour. High humidity also inhibits perspiration from evaporating rapidly and thus cooling the body.

Even mild dehydration with a 1-2% loss of body weight can cause weakness, fatigue, nausea, loss of coordination, dizziness and gastric problems. A 5% loss can result in heat exhaustion, which is characterized by nausea, dizziness and fainting. Severe dehydration, defined as a loss of 9-15% of body weight, is a life threatening medical emergency.

Mild-to-moderate dehydration can usually be treated simply by drinking a sufficient amount. To remain hydrated you must drink before, during and after playing. Relying on thirst as an indicator of your body’s need for water is a poor method because thirst lags behind actual dehydration. A better method of assessing the level of hydration is to note the color of your urine. If it’s dark yellow or amber you are most likely dehydrated. If it’s clear or straw colored you are well- hydrated.

Mild dehydration has these signs and symptoms:
• Excessive thirst
• Sleepiness or tiredness
• Dry mouth
• Decreased urine output
• Muscle weakness and fatigue
• Headache
• Dizziness or lightheadedness

Severe dehydration, a medical emergency, is characterized by:
• Extreme thirst
• Irritability and confusion
• Very dry mouth, skin and mucous membranes
• Lack of sweating
• Little or no urination (urine produced is dark)
• Dry, inelastic, shriveled skin
• Low blood pressure
• Increased heart rate
• Fever
• Delirium or unconsciousness

HYDRATION BEFORE AN EVENT
Hyperhydrate just before the start of play in hot weather. This can be accomplished by drinking 15-20 ounces of cold water or an electrolyte solution. Doing so will help delay the onset of dehydration.

The maximum rate of fluid absorption by the gastro-intestinal tract during exercise is approximately 30 fluid ounces (890 ml) per hour. The rate of fluid loss through sweating during exercise in the heat is close to 60 ounces per hour. This means that with prolonged intense hot-weather exercise, the onset of dehydration is inevitable. Drinking about 8 ounces of fluid every 15 minutes is the most effective way to delay dehydration during hot-weather exercising.

Understand that there is a large range among athletes when it comes to the volume of fluid lost while exercising in the heat. The rate is dependent upon the quickness of ingestion and absorption, the type of fluid ingested, the amount of sweating, the rate of gastric emptying, the intensity of training, plus the percentage of body fat, age and numerous other factors.

Bottom line: Take time to understand your hydration capacity and experiment with sport drinks and the amount of liquid consumption during those hot pickleball days.

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Alan Bragman is a chiropractor living in Atlanta, Georgia. He is a former Cat 3 cyclist and nationally ranked table tennis player and inline speed skater. He was on the medical advisory board at Bicycling magazine for 10 years and has written for numerous other sports publications.