As the weather takes a turn toward summer here in New England (finally), you may notice that you feel a lot more sluggish during and after workouts. A little thing called dehydration may be creeping up on you without you even knowing it!

Being even mildly dehydrated can affect your performance. Sport scientists have noted that your body’s ability to perform high intensity exercise decreases by up to 45% with a sweat loss of only 2% of your body weight.

So if you’re 150 lbs and you sweat out about 3lbs (48oz) of water during a run, your performance can be significantly impacted in a negative way. While 48oz can seem like a lot, think about a long run on a hot day – it’s not entirely outside the realm of possibility that you would sweat that much.

So how do you know how much water to drink during exercise? Perform a simple sweat test – Kyle explains how:

When it comes to sweating and staying hydrated, it’s water in, water out. Your water intake must match what your body is expelling. The sweat test Kyle describes above helps you determine what that quantity is.

Happy sweating to everyone!

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