Staying hydrated is important for your health. When you exercise you lose water through sweat, the moisture in your breath, and through your body’s normal filtration and the creation of urine. Your body’s electrolyte concentrations change when you add or lose water. Maintaining a proper electrolyte balance will avoid dehydration sickness, and keep you performing at your best. It can be hard to calculate how much water you are losing, and then you may not know how much water you should consume to replace it.
Before you try to calculate how much water is lost, it is important to know if you are already well hydrated to begin with. To ensure this, it is recommended that each day males consume ~ 128 oz. of water, and females drink ~ 90 oz. water. Assuming you are well hydrated, start by weighing yourself before your workout and record it. All gyms have scales. During the workout keep track of how much you drink. Most bottles are labeled with measurements. Once your workout is done, weigh yourself again and record it. The difference in your pre minus post exercise weight is your water loss in pounds. For example if you weigh 165lbs before exercise and weight 163 post workout, you lose 2 lbs. of water.
To properly rehydrate, drink 16 oz. of water for every pound lost. Using the same example, 2 lbs. is 32 oz. That’s a lot of water to drink at once. Let’s say its 5 lbs. of water lost; that’s 80 oz.! It’s not possible to absorb all that water at one time so the key is to rehydrate over time. You can reduce how much water you lose by simply drinking more during the workout. Every 15 minutes you should be consuming a few oz. How much depends on the exercise, climate, sweat rate, etc. A good estimate can be calculated by multiplying pre exercise weight by 0.02 to find the acceptable sweat lose, according research from Central Washington University. Then multiply that number by 16 to determine how many oz. you will need to consume in total. Next divide this by the number of minutes you exercise to find the amount of oz. you need to consume per minute to keep up with the water loss. Dividing by 15 minutes will give you an approximate volume to drink each 15 minutes.
- 165 * 0.02 = 3.3lbs.
- 3.3lb * 16oz/lb = 52.8oz
- 52.8oz / 60 minutes = 0.88 oz/min
- 0.88 * 15 min = 13.2oz to be consumed every 15 minutes for one hour
Water is necessary for recovery and acts as the transport fluid for all chemical reactions in your body. Stay hydrated, stay health, and stay fit!
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