Staying properly hydrated is one of the key measures we can take to remain healthy. Being well-hydrated is imperative for concentration, memory, mood, cognitive abilities and of course, our motor coordination and physical function. This is true for both runners and non-runners alike. Especially in the cold winter months, it can be difficult to remember to hydrate. We believe that a solid understanding of the importance of hydration is a critical factor in remembering to drink water and keep hydrated. When we know how much fluids will help us, we will be more likely to remember them!
The Damages of Dehydration
According to the Mayo Clinic in the US, “dehydration occurs when you use or lose more fluid than you take in, and your body doesn’t enough water and other fluids to carry out its normal functions” (https://www.mayoclinic.org/diseases-conditions/dehydration/symptoms-caus...). Scientists have discovered that dehydration of just one percent has the ability to negatively affect a person’s mood, memory, and motor function, and this number could be even lower and requires additional study (https://www.ncbi.nlm.nih.gov/pubmed/17921465). When our bodies become dehydrated, brain fluid decreases, which limits proper brain volume and cell function.
As we become dehydrated, our blood also becomes thicker and more concentrated. This thicker blood is then harder to move around our body, causing our heart and cardiovascular system to work even harder to maintain proper blood pressure and temperature. When our blood is thick from dehydration, our heart is forced to delegate most of its oxygen-rich blood to our working organs and other “non-essential” organs, such as our skin, miss out. When our skin does not receive the hydration it so desperately needs, we tend to overheat. This increase in internal body heat also causes us to feel fatigued, sluggish, and like our thoughts are clouded.
Dehydration can also cause anxiety, muscle cramping, headaches, and a myriad of other health concerns.
Dehydration and Runners
Dehydration is especially damaging for those who lead an active and healthy lifestyle - especially runners. We lose body fluid during all of our normal activities, and even more when we engage in physical activity or experience excess heat.
Recently, researchers studied the effects of hydration on about a dozen runners on two occasions. To conduct the study, the researchers asked the runners to complete a 75-minute evening run and a 10k run the next morning on two separate occasions. On one trial, runners were instructed to replace 75% of their lost body fluid after their evening run. On the other trial, they were told to replace 150% of their lost body fluid.
The results of the study found that when the runners hydrated 150% of their lost body fluid after their evening run, their 10k run the following morning were an average of one whole minute faster than when they only rehydrated to 75%. This number may seem insignificant, however, it could be the difference between running a marathon in 3:52 or 4:00. It is also safe to assume that the longer the run, the more intensely the effect of dehydration will effect runners (https://www.active.com/running/articles/what-is-proper-hydration-and-how...).
How to Stay Hydrated During Training
Although your personal hydration needs will vary depending on your weight, size, metabolism, and even your clothes, there are some basic standards to live by. Here are a few important tips.
1. Drink whenever you can. This includes rest days. When training, it is good habit to drink multiple times throughout the day. Have a glass of water when you wake up, at each meal and when snacking, as well as 60-minutes prior to bedtime.
2. Hydrate during runs that last longer than 60-minutes. A lot of runners don’t like to carry a bottle with them when they run. This is fine as long as you have another hydration plan for runs lasting 60 minutes or longer.
3. Look at your urine before you train. This one may seem gross, but our urine tells us a lot about our hydration status. Before a training session, look at the color of your urine. If it is darker than a straw yellow, drink one or two cups of water before you begin training.
4. Rehydrate fully. After a run, it can be tempting to drink a bit until your thirst subsides and let that be the end of it. It is important to replenish over 100% of your body fluids after each session.