The Basics of Hydration
Hydration plays a huge role in athletic performance! Your fluid requirements are different from the person running next to you and even the person running next to them! This is because, according to the ACSM, sweat rates can range from 1 to 4 pounds per hour depending on a variety of factors. Some of these factors are sport, body size, intensity, clothing, the weather, your level of training, and whether or not you’re acclimated to the heat.
What is water’s role in the body?
Before we get started, it would probably be helpful to know what water does for your body in the first place! This fun fact will really drive home water’s importance: without water, death usually occurs in 7 days. (5)
- Helps digest food
- Regulates body temperature via sweating
- Transports nutrients and oxygen to working muscles
- Eliminates metabolic waste
- Lubricates joints and cushions organs and tissues (1)
Are you dehydrated?
The best way to determine whether or not you are hydrated is to take a closer look at your pee. More specifically, you’ll want to note the color and quantity. According to the NCAA, the lighter your pee, the more hydrated you are. If your pee is yellow, you could be mildly/moderately dehydrated. If your pee is dark, you are probably dehydrated.
You’ll also be able to tell if you’re dehydrated by taking a closer look at how you feel. Some signs of dehydration are chronic fatigue, headaches, and lethargy. (1)
What is sweat?
Sweat is not just water – it also contains electrolytes. Sodium. Potassium. Calcium. Magnesium. According to this study, complete restoration of fluid balance immediately after exercise is an important part of the recovery process. In fact, rehydration after exercise can only be achieved if both the electrolytes and water, are replaced. You know how I mentioned earlier that a person’s fluid requirements are super individual? That is in part due to the fact that a person’s sweat composition can vary considerably from person to person!
Dehydration and Performance
You might be wondering what is happening to your body when you’re dehydrated. In short, dehydration is a stress to the body! Your body temperature and heart rate increase, you burn more glycogen, and focusing becomes more difficult. (1)
Once you reach 2% fluid loss, you’ll find that you won’t be able to fight the heat very easily. Your cardiovascular system and your capacity to exercise will also start to suffer. (5) Logically, the more dehydrated you are, the more you’ll feel these stressors.
Fluids Before, During, and After Exercise
Nobody wants to start their workout in a hydration deficit! You’ll want to make sure that you drink some water before you exercise so that your body is in water balance. This is particularly true if you’re running in a hot environment. If you’re planning on running in a hot environment, drinking a little extra water the day leading up to your race can have a ton of benefits. (5)
- Delays dehydration
- Increases sweating during exercise
- Diminishes the rise in core body temperature
The goal? Drink 2-3 mL per pound of body weight at least 4 hours before your workout. The four hour window will give your body time to eliminate excess water beforehand so that you don’t have to stop and pee during your run! (1)
Too much of a good thing can be a bad thing! Overhydration is possible. If you drink too much water, you might dilute your blood sodium levels. (1)
While you’re exercising, you’ll want to prevent dehydration so that your performance doesn’t suffer! You might consider hydrating while you workout if you are working out hard enough to be worried about dehydration. (1) Try to get in a mix of water and electrolytes. Ideally, 110-170 mg sodium and 20 to 50 mg of potassium per 8 oz of water. (1)
Once you’re through with your run, you’ll want to full replace all of the water and electrolytes that you lost! Drinking 50% more fluid than you lots in sweat will improve recovery from dehydration. (1) You’re better off sipping those fluids versus drinking it all at once to maximize fluid retention. (1) Depending on the duration of exercise, intensity, and amount of sweat lost, you might need to increase your consumption of salt by sprinkling a little bit on your food throughout the day. (1)
How do you determine how much fluid you lost in your sweat? One of the easiest ways to do this is to monitor changes in your weight before and after exercise. Each 1 lb of body weight loss = 450 mL of dehydration. (5)
There are a ton of different sports drinks on the market. It can be super overwhelming to pick one! According to Nancy Clark’s Sports Nutrition Guidebook, a good sports drink has three basic components: good taste, carbohydrates, and sodium.
You’re probably wondering why she mentions good taste, right? Well, she makes a good point. If you enjoy the sports drink, you’re more likely to actually drink it! If your workout requires a source of energy in addition to hydration, you’ll also want to choose a hydration option that has some carbs. The ideal ratio of carbs to fluid is 13-18g carbohydrates per 8oz/240mL. (1) Too little carbs will leave you with not enough energy and too many carbs will decrease the speed of absorption. Finally, she explains that sodium plays a super important role in hydration! Sodium both stimulates thirst and enhances fluid retention. (1)
8 oz of pure coconut water has 45 calories, 25mg sodium, 470mg (10%) potassium, 11g sugar, 4% calcium, 4% magnesium, and 4% phosphorus.
This study compares 4 different hydration options: bottled water, pure coconut water, coconut water from concentrate, and carbohydrate-electrolyte sport drink. They found little difference between the four tested conditions regarding markers of hydration or exercise performance in young, healthy men. The take away? Good old coconut water can hold its own when compared to regular sports drinks!
Adding a small amount of electrolytes to your water will help your body hold onto and use that water better than water alone. (5)
My favorite electrolyte powder is the Vega Sport Electrolyte Hydrator. It tastes great (I like the berry flavor over the lemon lime) and it has all of the essential electrolytes your body needs to stay hydrated. My favorite electrolyte drink is Nooma. The flavors are so good – blueberry peach is my favorite. Because there are no sugars added, it’s not overwhelmingly sweet either. I 10/10 recommend!
Homemade Sports Drink
Check out my recipe for a homemade sports drink! Making your own sports drink is cheaper, healthier, and tastier! This recipe is super customizable and forgiving. I like to get fun juice mixes from Trader Joe’s to make my homemade sports drink, but any juice will do.
- 2½ cups water
- 2 cups coconut water
- ½ cup favorite juice
- ¼ tsp sea salt
- Mix ingredients together. Refrigerate. Shake well before consuming!
1 Clark, Nancy. Nancy Clark’s Sports Nutrition Guidebook. 5th ed., Human Kinetics, 2014.
2 “Assess Your Hydration Status.” Http://Www.ncaa.org, NCAA, www.ncaa.org/sites/default/files/Assess Your Hydration Status.pdf.
3 Maughan, R. J., and S. M. Shirreffs. “Recovery from Prolonged Exercise: Restoration of Water and Electrolyte Balance.” Journal of Sports Sciences, vol. 15, no. 3, 1997, pp. 297–303., doi:10.1080/026404197367308.
4 Shephard, R.j. “American College of Sports Medicine Position Stand: Exercise and Fluid Replacement.” Yearbook of Sports Medicine, vol. 2007, 2007, pp. 254–255., doi:10.1016/s0162-0908(08)70206-x.
5 McArdle, W. D., Katch, F. I., & Katch, V. L. (2013). Sports and Exercise Nutrition(4th ed.). Baltimore, MD: Wolters Kluwer.
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