How Much Water Weight Can a Player Lose During a Game?

A burly lineman can sweat through upward of nine pounds of fluid















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To reach the pro level, football players must compete aggressively. But to keep charging ahead at full steam, they also need to be vigilant about their health, which means eating and drinking right. In this extreme sport, just how much water can these pro athletes sweat through?


The body loses moisture through perspiration as well as through respiration (think of your breath fogging a window). Both of these processes speed up during exercise as the body works to cool itself down with sweat, which evaporates from the skin, taking heat with it, and by breathing harder to get extra oxygen to the muscles. Pile these factors on to a hot summer training session under heavy protective gear, and you have a recipe for some serious fluid loss.

To estimate for the amount of moisture lost, trainers subtract a player's postgame weight from his pregame weight. The difference is approximately how much fluid they have lost—and not yet replaced.

Athletic trainers usually try to make sure players don't lose more than about 3 percent of their overall weight during a practice session (although some may lose more). So, a running back might drop four to five pounds (around two kilograms) during a game, and a lineman might expend closer to nine pounds (four kilograms), says Chris Fischetti, an athletic trainer for the Buffalo Bills.

If a 300-pound (135-kilogram) lineman loses about 3 percent of his body weight, he has sweat out 1.08 gallons (4.09 liters) of fluid—which means that he would need to drink about 17 eight-ounce (23.5-centiliter) glasses of water to rehydrate after the game. That's a good deal more than the daily water intake recommendations for physically active adults, which are currently set at the equivalent of about 15 eight-ounce glasses for men and about 11 for women. Athletic trainers encourage the players to keep drinking fluids throughout games and practices, even if the athletes don't feel thirsty.

But water doesn't just come from the tap. Many foods, such as fruits and vegetables, also provide fluids and generally make up about a fifth of people's total daily water consumption.

And pro athlete or not, getting enough fluids is important because dehydration can lead to suboptimal performance, and in extreme cases lightheadedness and loss of consciousness. And when coupled with high temperatures and high humidity, such as those often experienced during intense NFL summer training camps, the body can overheat, leading to heat exhaustion or heat stroke—a serious medical condition.



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  1. 1. rodrigobernardo 11:19 AM 11/11/10

    It is recommendable to be consistent not only on the use of main units but also, when comparing quantities, on their sub units.

    If the authors start with litres, they should stick to that and go on to 17 x 0.235l, not moving to centilitres, which anyway are rarely used and in this awkward usage entailed a further decimal point, the choice thus being either litres or millilitres.

    It would have been even better if those 17, 15 and 11 x 23.5cl (sic) had been translated into their volumetric equivalents, 3.995l, 3.525l and 2.585l , which again could be shortened to 4l, 3.5l, and 2.6l, much easier to understand.

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  2. 2. candide in reply to rodrigobernardo 01:39 PM 11/11/10


    I agree, they should be consistent.

    In addition they mention "football" - American Football (by the tags and NFL reference) and then discuss the whole article in metric terms.

    Eu Football (soccer) - metric terms.
    US Football - US measurement terms.

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  3. 3. kwgmatthies in reply to candide 03:33 PM 11/11/10

    Yes, the title link:

    "How Much Water Weight Can a Player Lose During a Game?"

    might induce anyone interested in any game to click, earning SA their pittance. Today, in my neighborhood, it is a great day for a game of chess in front of the fireplace, though I doubt I'll lose any water weight, even if the game lasts 40 moves.

    Does the ambiguity of title arise here arise from an a priori nationalistic focus, or is this simply another example of media manipulation, sports fans?

    Stay tuned for the answer....

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