I have been reading some rather interesting articles lately about dehydration and the effects on a diver. With lobster season almost upon us and the Florida shore dive season in full swing, I thought we should visit the topic of dehydration and diving. I was noticing after long shore dive days, I was parched and would occasionally get headaches. After a few years, doing multiple shore dives in a day, I now hydrate fully the day before slowly, loading up on H2O and making sure I have my vitamins in me. For those of you who have never shore dove before, it is fabulous and having steel tanks gives me the opportunity to get 2-2 1/2 hour dives enjoying everything I come across. Well, times this by 2 or 3 and you are talking a serious workout during the day!
Also a scuba diver can lose fluids through sweat or urination. Yes, divers do sweat even underwater. But breathing causes the most loss of water for divers. It is not difficult to achieve the proper level of hydration before and while scuba diving. In warmer weather and for longer dives, you will need to drink more fluids. Drink slowly, so your body gets enough time to absorb the fluids without the kidneys getting overwhelmed. But remember to avoid caffeinated drinks like coffee and colas or any alcoholic beverages for many hours before the dive.
What does dehydration do to a diver?
- Dehydration can increase you chance of decompression sickness. According to experts you don’t “off gas” properly if you are dehydrated.
- The fatigue factor. Dehydration causes fatigue. Muscles don’t work as efficiently when you are a quart or more dehydrated and you get tired sooner. At a water loss equivalent to 3 percent of body weight (i.e., 2 quarts for a 150-pound diver), your muscular endurance diminishes. You don;t tend to be as observant on your gauges, you are tried swimming to boat, it hurts to get up ladder.
- The heart factor. Dehydration also causes cardiovascular stress. At four percent water loss, your heart must work harder to make up for a lower blood volume. That leaves it with less reserve capacity for dealing with the stress of, say, a long surface swim against a current.
- Having fun is hard work. You work harder than normal, hefting tanks and weights, struggling into neoprene and finning through the water. So you sweat more and breathe harder.
- You have to “go” more often. In the water, two processes—immersion dieresis and your body’s reaction to cold—both trigger the urge to pee, so you lose more water through your bladder than normal. In response to cold, your body constricts blood vessels in your arms and legs, sending it back to your trunk in order to conserve heat. For reasons scientists haven’t quite figured out, simply going under water causes the same reaction. In both cases, your body believes its total fluid volume is now too high, and orders urine to be made and dumped to restore the normal level.
- You breathe dry compressed air. You breathe dry compressed air, which your lungs moisten with water drawn from your body’s stores. So you lose more water from respiration than normal.
The result? By the end of the diving day you can easily be down a quart or two of fluids.
- ok, you are dive traveling in tropical climates with tasty rum punch and repeat six days … Air travel means the exercise of lugging luggage, plus hours of breathing dry airplane air. Your tropical destination includes more heat than you’re used to (more sweating), and perhaps more air-conditioning—which dries the air.
Terry Giles brought up some great facts and tips for countering these effects.
Remember that we are being pressurized when diving. You know the whole, don’t hold your breath to the top, slowly exhale on ascent? Well these pressure will also add pharmacological effects. According to Giles, “Increasing pressure will typically accelerate and change many of the body’s metabolic reactions. Imbalances at depth due to dehydration or electrolyte depletion can create output issues for a diver just when they want no new issues to deal with. At depth, we know CO2 Buildup is a dramatic problem compared to on land. We know that heat loss in cooler water creates huge thermal demands on the body. Just these 2 issues alone should be enough for most divers to consider that if a better way exists, they should be using it!”
Sodium and potassium are also important for optimal dive performance. I make sure I eat a banana every morning when diving. Helps with the cramp issues. You are in the water, you don;t really notice if you are overworking as you aren’t sweating. You don;t feel overheated because you actually tend to get colder the longer you are down. Signs are different. Keep in mind that a diver’s body works harder and overtime to keep your body’s vital organs warm. If you are getting cramps, you are already dehydrated.
Will sports drink help like gatorade or powerade?
According to Giles, there are two levels of hydration.
“Level One: Extracellular Hydration – extracellular hydration occurs outside of the cells. Extracellular refers to the fluid outside of the cells, which is found in three compartments that collectively equate to 20% of the body’s water. Water and high sugar sports drinks like Gatorade® fall under extracellular hydration. Water will cool your core temperature but is slow to actually migrate into the cells. Sports drinks replenish some electrolytes, but usually not in proper balance; therefore do not stimulate migration into the cells. Also most sports drinks are very high in sugar – which too impedes actual cellular hydration, as well as creating other undesirable side effects such as insulin spikes, etc. Level Two: Intracellular Hydration– intracellular occurs actually inside the cells and refers to the fluid inside the cells which equates to over 70% of the body’s water and represents 40% of our total body weight. True intracellular hydration is far more complicated than drinking water or a sports hydration beverage that is simply some electrolytes and possibly some carbohydrates.
Drinking water will improve your overall hydration status, but it will not significantly alter the ratio of intracellular to extracellular fluid. Drinking most sports hydration drinks will do little to nothing to improve your intracellular hydration and in fact could actually hinder your performance due to high levels of sugar and incomplete or unbalanced electrolytes.”
My thoughts about drinking soda on the boat or before dives:
Most boats will give you complimentary soda in between dives. This is bad my friends. Carb and sugar overload and way too much sodium and not enough potassium. To clarify, your muscles require a drink with about twice the potassium to the sodium it contains, and if the drink is high sodium with little or no potassium, you are actively destroying the essential activity of your body’s “sodium-potassium pump”.
Another problem with sodas is that they act as dehydrating diuretics. Both caffeine and sugar cause dehydration.
Also soda is loaded with caffeine which is a diuretic and causes an increase in urine volume. High concentration of sugar is drawing off water because your kidneys try to expel the excess sugar out of the blood. When you drink a caffeinated soda to quench your thirst, you will actually become thirstier. My husband used to coach youth football. This was his peeve, kids drinking soda before a game. He would say, “drink that soda and you have to drink twice as much water to get rid of it and rehydrate.”
There is an easy way to tell if you are dehydrated…check your pee.
Its color, amount and frequency will change if you are dehydrated. If you’re drinking enough water, it will be pale yellow or clear (Nancy Clark, the New York Times nutrition writer, says your urine should be the color of lemonade, not apple juice), of your normal volume, and you’ll feel the urge every two to four hours. Darker urine, less of it and the need to go less often means you’re dehydrated.
So what should you drink when diving? I would recommend water, juice or tea. Stay away from the high sugar and artificial drinks. We take a cooler. Drink a bottle before we go in water and we bot hslug one straight after coming up from a dive. Let mother nature treat your body good. Diving is a sport and should be treated as such, you wouldn’t go play a game of football in 90 degree weather and not hydrate properly.
I will also say that I can generally kill a cold frosty beer as soon as my dive is over, once I have slugged a cold bottle of water.
Be careful, be safe and think before you drink (whatever it may be)