Dehydration Causes Major Strength Decreases!

A 2008 study[1] concluded that muscular power decreased by up to 19% at a dehydration level of 3% (that’s 3% of total body weight). Interestingly, the study participant’s perception of fatigue increased by a massive 70%!

What happens when you dehydrate?

Research shows that as little as 1 percent dehydration negatively affects your mood, attention, memory and motor coordination. Data in humans is lacking and contradictory, but it appears that brain tissue fluid decreases with dehydration, thus reducing brain volume and temporarily affecting cell function.

Normal water needs range drastically due to a number of factors, such as body composition, metabolism, diet, climate and clothing.

Surprisingly, the first official recommendation about water intake was made as recently as 2004. According to the Institute of Medicine, the adequate water intake for adult men and women is 3.7 and 2.7 litres per day, respectively.

Around 80 percent of total daily water should be obtained from any beverage (including water, caffeinated drinks and alcohol!) and the remaining 20 percent from food.

But of course, this is just a rough guide. Here’s how to monitor your own hydration:

Track your body weight and stay within 1 percent of your normal baseline. You can work out your baseline by averaging your weight (just out of bed, before breakfast) on three consecutive mornings.
Monitor your urine. You should be urinating regularly (more than three to four times per day) and it should be a pale straw or light yellow colour without strong odour. If less frequent, darker colour or too pungent, then drink more fluids.
Be conscious about drinking enough fluids. Your fluid consumption should prevent the perception of thirst.

— from Here’s What Happens to Your Body When You’re Dehydrated, by Toby Mündel from Massey University, and originally published by The Conversation.

[1] Active Dehydration Impairs Upper and Lower Body Anaerobic Muscular Power – Jones, Leon C; Cleary, Michelle ; Lopez, Rebecca M; Zuri, Ron E; Lopez, Richard, Journal of Strength & Conditioning Research: March 2008 – Volume 22 – Issue 2 – pp 455-463

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