Sweat Trials and Hydration for Training and Racing!

The summer race season is finally here with races like the Playtri Festival, Buffalo Springs Lake 70.3, and Take on the Heat right around the corner.  With temperatures rising, hydration during racing and training is becoming even more crucial for peak performance and general safety. For example, this past weekend at Ironman Texas it was hot and humid; many athletes found themselves slowing on the bike, walking the run, or not finishing the race because of poor hydration plans.

No matter your age or abilities, you should be drinking 20 to 60* fluid ounces per hour. To find out accurately how much you need to drink, you need perform sweat trials.  You will need to perform these sweat trials in many different environments as they are effected by temperature and humidity.  

The method to perform sweat trials is straightforward:

·      Start by weighing yourself with no clothing

·      Ride or run for one hour keeping track of how much you drink in ounces

·      After the workout weigh yourself again with no clothes

·      Subtract your post-workout weight from your pre-workout weight and convert to ounces

·      Add how much you drank to the value above (For example, if you lost 1 lb or 16 ounces and drank 16 ounces of fluid, your total fluid loss is 32 ounces.)

·      You can divide that number by 6 and get the amount of liquid per 10 minutes

·      You will need to do this for the bike and run

I cannot stress enough: if you start drinking when you get thirsty it is too late!  It is imperative to have a hydration plan going into your workout. That is why I recommend trying to drink every 10 minutes.  Furthermore, during your training it is good to experiment with various liquids to determine what you like to drink and can tolerate during different workout types.

Now that we have decided how much liquid you should be aiming for, it is time to decide the best way to fulfill your hydration needs.  To start with, I personally like the Speedfil Z4+ on the bike as it has a bottle, straw, and mount for your bike computer.  The Z4+ cage uses a standard, dishwasher safe bottle so you don’t have to worry about ruining a custom bottle after the first use with something other than water.  On the run I like the Fuel Belt 2 bottle hydration belt.  I have found the velcro closure allows for more adjustability than most buckle type hydration belts and keeps the belt well fastened during running at all intensity levels.  As mentioned above, 20 to 60 fluid ounces per hour is what you should be aiming for. Neither the Speedfil nor the Fuel Belt will hold the total amount of liquid that you will potentially need for your longer workouts. On both the bike and run it is good to plan your routes around loops or plan stops along the way to refill your bottles. 

*60 fluid ounces applies to a very small percentage of athletes. The majority of athletes will require between 25 and 40 fluid ounces per hour.