Why Is Exercise & Drinking Water Important?

Water is essential for human function. The body is made up of about 50 to 70 percent water, depending on hydration status. Muscle is about 70 percent water, so humans can only go a few days without it. About 80 percent of water should be taken in through liquids, but food contributes to about 20 percent of total water intake.

Average Requirements

Water helps cushion joints, aids in cellular function, carries nutrients to the cells, prevents constipation and regulates body temperature. The Food and Nutrition Board released new guidelines in 2004 that states people should let thirst be their guide. Generally, people consume enough water through food and beverages. However, a daily general recommendation for men is to consume 125 ounces and for women to consume 91 ounces daily.

Exercise Requirements

During exercise, the body utilizes more water than average, meaning it must be replenished more frequently. The American Council on Exercise recommends drinking about 17 to 20 ounces two to three hours prior to exercise. After commencing, drink 7 to 10 ounces every 10 to 20 minutes. If exercise lasts longer than 45 minutes to an hour, drink something with electrolytes or sodium, such as sports drinks, to replenish sodium and potassium that is lost through perspiration. After cool-down, drink another 16 ounces of water for every pound lost during exercise to rehydrate yourself.

Extreme Weather

Extreme heat and humidity cause blood vessels near surface of the skin to dilate, leading to decreased venous return to the heart and reduced cardiac output. To make up for this reduced cardiac output, the heart has to pump faster to achieve the same results and deliver oxygen to working muscles. In high humidity conditions, sweat will not evaporate off the skin, which is the body’s main cooling mechanism. All of these factors can lead to higher instances of dehydration, so make sure to drink more water than normal in extreme heat. In extreme cold weather, kidneys increase urine production, flushing water out of the system faster, so it is also important to stay hydrated in the cold, even if thirst decreases.

Dehydration

J.G. Hunter and K.L. Carson of Clemson University describe dehydration as a 20 percent loss of body water, which can be life threatening. Symptoms of dehydration include muscle fatigue, extreme thirst, minimal urination of a dark yellow color, increased body temperature, nausea, constipation, lightheadedness, dizziness and headache. Chronic dehydration, or a state of constantly being a little dehydrated, can lead to kidney stones, increased cancer risk and heart attacks.

Tips

When you wake up first thing in the morning, drink a glass of water. Add slices of lemon or cucumber to water to change the flavor. Carry a container of water throughout the day. People often get thirsty throughout the day, but because a water source is not near, they push the urge to drink away. Drink water with meals and snacks.