Hydration, performance & recovery
So you’re heading out for a long run. 9:00am Sunday morning. You have your mitts, your hat, and a couple Powergels tucked in your pocket. Smart. After a hearty breakfast of oatmeal and peanut butter on toast – you head out towards the park. Pausing briefly as you remember you forgot to bring your water bottle – you shrug and ease into your warm up jog… after all – there are plenty of fountains in the park.
Strike one.
You’re an experienced runner. You’ve taken this route before. Besides… it’s cold out. Not a ray of sun breaking through the clouds. You figure you won’t get thirsty – you had two cups of coffee with breakfast.
Strike two.
2 hours later, you burst through your front door, gulp down a glass of juice, shower, and have a nice big sandwich. Exhausted (but in a good way) – you crash in front of the tv. You have a nagging headache, but figure it was the glass of wine you had the night before with dinner. It isn’t until 4:00, as you watch a “pull ups” commercial that it dawns on you that you haven’t peed since you woke up. Also, you haven’t moved much since you completed your run. Uh oh.
Strike three.
Of all the physiological issues that can decrease performance during exercise and cause stress to our systems, dehydration is arguably the most important. Not only does it cause early fatigue but it also impairs cardiovascular function. Dehydration is a surprisingly common occurrence, even during exercise in cold weather and among well-trained athletes.
An athlete can become dehydrated in as little as 30 minutes, or when fluid (sweat) loss exceeds 1% of body weight. Well-trained athletes sweat more, and they start sweating at a lower body temperature. (The function of sweating is to cool the body and a well-trained athlete cools his or her body more efficiently than an untrained person).
The thing is, exercise blunts our thirst mechanism so we can’t rely on thirst as an indicator of dehydration. In fact, most active people have experienced the symptoms of dehydration but probably haven’t been aware of it. If you’ve ever felt really sluggish hours following a workout? That’s what is called an “aha!” moment. Yup, that’s dehydration.
Plain, cool water is a very effective fluid replacement. For efforts lasting 60 minutes or less it’s the most readily available and cost effective option. For training requiring more than 1 hour of continuous effort, a carbohydrate-electrolyte sports drink (Amino Vital, for example) is a better choice, as electrolytes are lost in sweat. The primary electrolytes lost in sweat are sodium, chloride, potassium and phosphorus. Be careful not to drink plain water following extensive exercise, as it will actually dilute your electrolytes even further, resulting in nausea. Most sports drinks contain all of the key electrolytes in doses large enough to help you replenish your lost stores. Sadly, beer is not a sports drink.
Summing it up: five rules of proper hydration:
1. Don't wait until you're thirsty to start drinking. By then, it could be too late. Drink early and often--every day. Staying well-hydrated throughout the day benefits you in ways beyond your training. It helps keep you alert and will prevent that dull, groggy feeling that slows you down in the middle of the day. Your heart has to work harder to pump as you become dehydrated since sweat is made from fluid in your blood and your blood becomes thicker as it is lost. For the record this is not an effective “cardiovascular” workout.
2. If you are about to compete: an hour or so before your run or race, fill up your reserves by drinking 2 cups (16 ounces) of water and/or sports drink. I know, you’re afraid you’ll need to pee right when the guns go off. Which is the beauty of the chip system: even if you start late – net time allows you to visit the portapotties without sacrificing your PR. Take in between 6 to 12 ounces of fluid every 15 to 20 minutes during the effort. If you're going for less than an hour, you'll be fine drinking plain old water. Your body's stores of carbohydrates and electrolytes are sufficient to carry you for at least that long. Similarly, if you aren’t competing and are only concerned about adequate hydration on a day to day basis, water is definitely the best choice. Green tea is also a terrific choice. Coffee and other caffeinated drinks have a slight diuretic effect, and so they don’t count. In other words, your Mountain Dew just became a Mountain Don’t.
3. Before and After. Weigh yourself before you head out and again after your training. Drink roughly 16 ounces of sports drink/water for every pound of body weight you lost during exercise.
4. When you run (bike) long, use a sports drink. Study after study shows that for exercise lasting more than an hour, runners perform significantly better when drinking a sports drink than when drinking plain water. Stop thinking about burning calories and creating a deficit, and start thinking of your body as a fine tuned machine requiring prime fuel.
5. Don't go overboard. If you feel or hear sloshing in your stomach, you’re too full, and you don't need to drink for a while. Hyponatremia, or "water intoxication," (in simple English: over hydration) usually happens only during long, hot runs/workouts/races when one loses a lot of sodium through sweat and drinks excessive amounts of plain water. In doing so, one may unwittingly dilute sodium levels in our blood, setting off an electrolyte imbalance.
Follow these basic rules, and you’ll avoid all risks of shriveling into a prune on mile 9.
Be well!