Welcome to the Get Fit Guys, quick and dirty tips to get moving and shape up.

My name is Brock Armstrong and I am the Get Fit Guy.

How important is staying hydrated during exercise?

I mean, really.

If you are lugging around a fanny pack water bladder or a bunch of different sports beverages,

well, you know what? You may be doing it wrong.

When I first started running, semi-seriously, I diligently carried a water bottle on my belt,

as instructed by all the running magazines and the running websites.

Then, as my thirst for the sport grew, I graduated to, well, an embarrassingly fanny pack-style beverage

bladder. But by the time I achieved the level of having a shoe sponsorship and coaches,

I wasn't carrying anything with me at all. A few sips at some random water fountains or the on-course

aid stations, well, they worked just fine. And there's a reason that I tell that story. For many

years, the rule of thumb for exercise hydration has been that if

you sweat out more than 2% of your body mass, your performance will decline. And that's based on

military research that was meant to prepare U.S. soldiers for hot climate combat during the Second

World War.

Now, in practical terms, that rule means that a man who weighs 80 kilograms or 176 pounds can only sweat out about 1.75 liters or about 60 fluid ounces of sweat before he will start to fall

apart, performance-wise anyway.

Now, the problem is that depending on how hard you exercise and also how hot it is where you're

exercising, well, you could potentially drip that much onto the gym floor in about an hour.

And even sipping from an electrolyte-laced water bottle may not stave

off that 2% loss. Now studies have shown that in the more jiggly types of activities, like running,

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