Editors note: Hydration: Planning Ahead To Keep Going was written by Dave Mackey for ATRA’s Trail Times Newsletter #26 in 2003. Dave recently survived a gruesome accident while trail running. You can help Dave and his family offset medical expenses and lost income on YouCaring.com.
Trail running combines many environmental factors that add significant stress on the body. Dirt, rocks, tree roots, standing water, rushing rivers, hills, altitude, sun, heat, and cold can be major obstacles in trail runs. When you choose a trail run or race you know in advance that you can not change or control the environment or terrain, but you can mitigate the impact of some external factors on your body by controlling hydration, electrolyte replacement, and food intake.
This article addresses hydration while electrolyte replacement and food intake will be tackled in a later issue of Trail Times. In the interim, keep in mind that all the water that enters your body should be matched with salts, sugars, and carbohydrates, and for ultrarunning be sure to include protein.
As soon as your cells start to become depleted, your body is no longer operating at 100% efficiency. When your body loses one liter of water, you lose 25% of your ability to produce kinetic energy. This does not necessarily mean that you will finish 25% slower, but a dehydrated condition will certainly add time to your run.
When you start a race you may know how much fluid you will drink at every aid station based on the positioning of the stations along the route, but what about before your run or race? You can work with the aid station logistics during an event, but hydration really should start in the days leading up to the competition. Runners should be drinking at least four liters of water per day. This baseline may vary between depending on runner weight and environment (dry or moist climate), but this is a general guideline. I personally drink this amount of fluid no matter what my running schedule is.
Individuals constantly lose and replace fluids. When running a trail race, especially at altitude in hot, dry conditions, the rate at which you lose fluids increases exponentially compared to sitting on the couch in a humid, sea-level home. No matter how much fluid you drink during a trail race, you will likely never replace fluid faster than the rate at which you lose it. You can try to balance your fluid levels during a race with ideal conditions — cool temperatures, moist climate — but at the end of the run you will still be somewhat dehydrated.
The key to hydration in a race or run is to drink early and often. The sooner you start drinking (best within 20 minutes), the better your chances are to offset the negative effects of fluid loss. In a trail marathon I drink all the way until mile 23, and if I have been able to ingest what my body needs, I feel that I will have enough to push through to the end.
Have you ever felt thirsty part way through a race? This is inevitable given that some trail races are more than 100 miles, but thirst can be an issue in races lasting only one hour. If you do feel thirsty, it is probably too late to replace the necessary fluids since you are already dehydrated. All you can do is delay the symptoms of dehydration. Is it best to leave your last few gulps of precious fluid in your water bottle or Camelback until you are closer to the aid station? No. The best place to store water is in your stomach. Keeping the flow of water to your system is critical. It takes time to replace the water that has been depleted from your cells and the typical runner can only absorb about one half-liter of water per hour through the stomach.
Some runners declare that they can not drink during a run because of stomach issues. Some runners who drink too much vomit as soon as they start running. It can take a long time to train your body to handle fluids in your stomach, but in order to have your peak run, you need to force yourself to adjust to fluid intake. Start by carrying a water bottle and drinking or sipping fluids during your training runs. Build up your fluid intake gradually and you will be able to handle the amount of fluids that are necessary to get you to the finish line of a race with as little dehydration problems as possible.
Have you ever had to pee during a race, but didn’t want to spare those precious 30 seconds to do so? If you think that you are hydrated simply because you have to urinate, you may be wrong so keep drinking. Remember, your urine can be gin-clear after downing a 16-ounce Java, but you know that the caffeine is causing dehydration at the same time. When you run a trail race the stresses and chemical changes in your body can cause you to have C2P2 (clear, copious pee-pee), but this in all likelihood still means that you are losing fluids faster than you are replacing them. So, keep downing the ounces! If you do not like to take time during a race to stop and drink, be assured that you will easily make up that time over the course of you run by having a more efficient and hydrated machine.
Timing It Right
So where is the balance? If hydration is so critical, should you head down to Der Sports Haus and buy one of those 100-ounce jobbers and keep topping it off at all the aid stations? Well, this is one strategy that ensures maximum fluid replacement and may work in the Vermont 100, but there are other ways for shorter runs.
The best strategy is to plan ahead and come into the aid station with an empty hydration system, having finished it off only minutes before you arrive. If you come into aid stations and always have fluid left in your hydration system, then you haven’t been drinking enough or you are carrying too much. If you are carrying too much it means that you have been hauling around extra weight, which adds to your time and cuts into energy expenditure. This is fine for runners who participate in events simply to enjoy the experience no matter what pace they travel, while making sure they have enough reserves regardless of the weight issues of additional fluids. The fine line for runners hoping to achieve faster times involves learning where their ideal hydration balance is so they don’t carry too much, or too little.
Experience is key, because it takes many training runs and races to know just how much fluid you can drink in a certain period of time and how long it will take to cover trail distances in specific races. You may average an eight-minute mile pace at the Hills of Cabin John Race on Block Island, but be relegated to a 20-minute mile pace during the final miles in the Pikes Peak Ascent. Figuring your trail race pace takes time and experience, and you will learn what works for you with trial and error. Until then, be somewhat conservative and carry extra fluids.
After all runs, not just races, be sure to replenish your fluids. In a race or hard training session that lasts between two and three hours, you could lose over 150 ounces of water from your body! For ultrarunners who are training or racing more than three hours, they have many more pounds of water weight to replace. It can take days, or even longer to return to a fully re-hydrated condition after an ultrarun. Get in the habit of regularly carrying a liter of water with you and sipping or drinking throughout the day, not only after a hard run. This practice will ensure that your fluid levels remain at an optimum level.
