In terms of fluids, you will want to make sure that you are taking in both some sports drink and water. Most over-the-counter solutions such as Gatorade or Ironman Perform have both carbs and sodium, meaning you'll be able to get in some energy (carbohydrates) while you are drinking. You can alternate water with a sports drink, and you'll want to back off the fluids with about 30-minutes before your long run.
More: Electrolytes 101
You'll know you are ready when you have go pee before you leave and your urine is light yellow to clear.
Step 2: During Your Workout
Drinking while working out is a no-brainer, but still so many folks don't take in enough fluids. For a hot day, your target is approximately four ounces of fluids per mile. As an example, most Fuel Belt bottles hold eight ounces of fluid, so a full four-bottle belt would get you through eight miles.
In addition to planning for your fluids, you actually need to consume them! If you have a watch with a lap function, you can simply drink every time it beeps. Remember that once you fall behind on your fluids, it's hard to catch up and still continue running. If you do run into this challenge, consider walking for a bit in order to let the fluids get into your system.
If you don't have a run with places to stop and reload your fluids, such as a water fountain or a convenience store, then you'll need to make your own loop. It can be from your house or car, but either way you need to have a way to replenish your fluids if you are going to have a successful long run.
The key here is choosing the right type of fluids. There are two factors to consider: flavor and content.
Everyone has their own individual preference for what flavor or type of beverage they prefer. When you choose your preferred beverage, make sure it's something you really like so you'll actually drink it. You'll need to test what it tastes like when cold and warm, at the start of your runs and at the end, when you need them the most.
In terms of content, I strongly recommend that you go with a performance beverage. Widely available solutions like Gatorade Endurance and Ironman Perform (by Powerbar) both have higher concentrations of sodium. This is key, as salt helps the fluids move through your system effectively. Water alone just won't cut it; hot days require that your replenish electrolytes, and ignoring that will lead to a very sub-par run.
More: 10 Tips for Hot Summer Runs
Step 3: After Your Workout
Once your long run is finished, the first order of business is to get a recovery drink into your system. Ideally this happens within 15 minutes of finishing your run. You are looking for something with a ratio of carbs to protein in the 4:1 range. If you don't want to purchase a recovery drink mix, you can substitute an eight ounce glass of skim milk with two tablespoons of chocolate syrup.
With your recovery in progress, take a second to review your fluids to see just how well you hydrated. More often than not, people loose focus on longer runs and don't drink everything as planned.
More: How Calculating Your Sweat Loss Can Boost Your Performance
Your post long-run window, like the pre-run window, lasts as long as the run itself, or at least until you have to pee. During this time you can alternate water and sports drink—just make sure that they are cold, as you'll be more likely to drink them.
Managing your nutrition is a critical part of being able to train to your potential. Quality training begets improved fitness, and improved fitness will set the stage for a great run. And now that you are a hydrating machine, you'll be ready for race day no matter what the weather brings. Good luck!
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