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TRAINING TIPS: Hot-Weather Hydration Planning

Coach Kevin Mackinnon's tips for staying hydrated in the heat.

“Where’s your water bottle?” one of the coaches from our triathlon club asked my daughter. “We’re only running for an hour,” she replied. “It’s not that hot and, besides, my dad always gives us the lecture about how he used to do two-and-a-half-hour hill workouts without a water bottle in sight.”

All of which was true, but since I’m the head coach of the group, it’s probably not great that she’s heard my spiel so many times she can recount it by heart. She first started hearing it when athletes from our training group would start looking for water before we finished the warmup. That’s when I would start recounting the stories about the good ol’ days when the Queen’s University cross-country team, in the midst of a four-national-championships-in-five-years streak, would routinely do long workouts in early September “without a water bottle in sight.”

My cavalier attitude towards hydration in those days got me into trouble at times. I finished a long run in Athens, Greece one summer and spent the next 24 hours trying to recover. My sister still claims my brain has never recovered from the extreme dehydration I suffered at a half-Ironman in 1986, in which I staggered through the last 5K and ended up in an ambulance at the finish with an IV stuck in my arm.

So, while I don’t believe that people need to carry a water bottle with them for a 15-minute warmup jog before a workout, hydration is nevertheless a critical part of any training plan – one that requires as much thought as you put into how many kilometres you run each week or what kind of speedwork you do.

It’s critical that you are properly hydrated during training and racing, which is why you need to have a bit more of a plan than simply to “drink lots of water.” Performance is dramatically affected by dehydration – a significant loss in your bodyweight due to fluid loss can dramatically increase the amount of effort it takes to keep moving and can decrease your performance. Too much water, though, can also be harmful – you can dilute the electrolyte balance in your body, leading to the potentially deadly condition of hyponatremia, a condition where your body can’t use all the water you’ve thrown into your system.

You can figure out your own fluid replacement needs by doing your own sweat-rate analysis. Weigh yourself before and after your workouts to see how much water weight you’re losing and gear your water intake accordingly. Make sure you never lose more than one per cent of your bodyweight during your runs. (A few years ago, during a sweat test performed by the Gatorade Sport Science Institute, I finished my hour-long fitness test at exactly the same weight I started. They felt it was most likely due to an awareness of my fluid needs after many years of long distance training – I attribute it to the free and easy access to as much Gatorade as I wanted.)

Here are some other tips that will help ensure you’re properly hydrated this summer:

1)      Make sure you’re hydrated before you start running. Your urine should be clear – darker and concentrated urine before you even start isn’t a good sign.

2)      For runs longer than an hour, add some sort of an electrolyte replacement drink to your hydration plan. Make sure you experiment with different drinks and concentrations to find the one that best suits your needs.

3)      Don’t wait until you’re too thirsty. Once you’re parched, it’s pretty much too late to get yourself back on track. Gulp small amounts on a regular basis throughout your longer runs.

4)      Come up with a hydration plan. Don’t make assumptions – figure out exactly what your needs are and take care of them.

So, was my daughter right? On that cool afternoon, for her 45-minute workout, she was just fine. Later this summer, though, she’ll need to forget her father’s diatribe and pack that water bottle when she heads out the door.

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