Hydration For Martial Arts Athletes
All athletes need to be properly hydrated to train and compete at their best. A 2% loss of fluids in an athlete's body causes an increase in perceived effort, and is already changing the body's ability to disburse heat, making the muscles less efficient. A fluid loss of 3-5% body weight reduces exercise performance noticeably and impairs reaction time, judgement, concentration and decision making - vital elements in all sports.
Body Weight Lost as Sweat vs.Physiological Effect
2% - Impaired performance
4% - Capacity for muscular work declines
7% - Hallucinations
10% - Circulatory collapse and heat stroke
Recognizing Heat Exhaustion
Pale skin, cool, moist
Tired, week, dizzy
Fast, weak pulse
Fast, shallow breathing
What to do for Heat Exhaustion
Stop exercise, get to a cool place, drink fluids.
Recognizing Heat Stroke (Center for Disease Control)
Red, hot dry skin (no sweating), temperature above 103F
Fast, strong pulse
What to do for Heat Stroke
Stop exercise, get to a cool place, call 911 - this is a medical emergency. Cool the skin by spraying water from a hose, or wet towels. Don’t give fluids, (emergency medical personnel will give intravenous fluids).
Hydration Plan for the Athlete
Before and after exercises
The body's digestive system can only absorb about 1 quart of fluid per hour, so an athlete must consume fluids before, during, and after exercise to replace fluid losses and minimize dehydration. When you are not exercising, you need to drink fluid every 1-2 hours depending on activity and climate; drink until you are satisfied each time. During the hour before exercise, drink 8 ounces of water for every 100 lbs. of body weight. Don’t let your thirst determine when you drink: Thirst sensation can wait to appear until you have lost 2% or more of your body weight.
Hydration during the first hour of hard exercise:
Hard exercise causes you to loose fluids faster. Your body cools itself by using water through evaporation from the skin's surface as sweat, and through evaporation in the lungs as your breathe. The fluid in the blood is used when you sweat, causing lower blood pressure; your body's cells become less efficient, effecting muscle and organ function. Cramps in the legs can come from exercise as a symptom of low fluids and low blood pressure. Low potassium can also be a cause in some cases.
Get the most from your Workout
Your goal is not to loose weight during exercise, maintain your weight by drinking water. Drink water every 10-15 minutes during exercise. (Ramtown Karate will give a break after a hard 30 minute exercise session- but you can keep a water bottle in your bag and get a drink sooner). Continue drinking water every 10-15 minutes. Gulp (don't sip) until satisfied each time. Sweat consists primarily of water and the electrolyte sodium, as well as smaller amounts of potassium, calcium and magnesium. You don't need a sports drink for this duration of training, a good balanced daily diet will provide you with the right amount of electrolytes and carbs.
Maintaining fluid balance during exercise helps sustain athletic performance by:
Optimizing control of core body temperature
Optimizing heart and circulatory functions, including heart output (stroke volume)
Maintaining the control of adrenalin
Reducing net muscle glycogen usage
Maintaining the fluid cushion around the brain, reducing the risk of brain injury
Preserving peak reaction time, judgement, concentration and decision making
Hydration for Training More than One Hour, or in Hot Weather
When exercising hard for two hours, a 150 lb. person could use 3 - 16 oz cups per hour, or a total of 6 - 16 oz cups in two hours. If the athlete did not drink water during this time, this is a 4% loss and significant dehydration.If he was behind in hydration before the start of training, he has risked heat stroke. Remember that you need the right amount of body fluids to keep you cool.
When training more than one hour, your muscles are using glycogen (stored carbs) and need replacement. Glycogen replacement is now necessary to delay muscular fatigue, and to slow the decline of mental alertness and judgement.
What to do when your workout exceeds one hour
Athletes that consistently exercise more than one hour learn how much they sweat. This amount changes depending on climate and type of training. Weigh yourself before and after workouts to learn how much fluid your body is loosing during exercise. Your goal is not to loose weight during exercise; maintain body weight with proper fluid replacement. Remember that a pound of body weight equals a 16 oz cup of fluid. Get to know your body: Refer to the urine color chart below. Use a sports drink (Not energy drinks) like Gatorade during hard exercise sessions that exceed one hour (National Strength and Conditioning Association). Electrolyte solutions will satisfy your body's need for salts, and are absorbed and used by the body faster than water alone. Carbohydrates fuel your body’s cells for more exercise, and keep you sharper mentally, but can slow the absorption of fluids. Sports drinks solve the problem by combining carbohydrates and electrolytes; your body gets what it needs at about the same absorption rate as water.
US Olympic Committee Recommendations for Sports Drinks:
Encourage your athlete to use them before, during and after training and stick with water as their preferred drink throughout the day outside of training times.
Carbohydrates: 14-17 grams per 8 ounces (a 6-7% carbohydrate solution).
Sodium: dependent upon athlete's sweat rate and sweat sodium concentration but range of 70-1266 milligrams per 8 ounces of fluid is recommended.
Fluid: depending upon athlete's sweat rate a range of 3-8 ounces per 15-20 minutes is recommended.
What about competing in hot climates like Okinawa?
When you acclimate to warmer, humid weather, your body will learn to sweat more and learn to reduce electrolyte concentration in your sweat. You will become accustomed to drinking more fluids. A marathoner may have two weeks to acclimate; you will rarely get this much time as a karate or combat athlete. Significant physical exertion on a very hot day can generate heat beyond a healthy body's ability to cool itself. You need to prepare for this.
When acclimating to a tropical climate, follow these rules:
Begin with reduced training and intensity.
Increase the volume and intensity of training as you begin to adapt.
Keep hydration as a major focus, use sports drinks when training over one hour.
Body weight, hydration rates, and other physical indicators must be monitored through the heat training phase.
Sunburn decreases your ability to cool yourself and causes fluid loss. Use sunblock with SPF 15 or higher. Wear a hat that provides shade and allows ventilation.
Wear light, loose-wicking clothing so sweat can evaporate. Consider clothes made with CoolMax®, Drymax®, Smartwool or polypropylene.
Pay attention to differences in local diet. Some local habits may help hydration, such as drinking miso soup (a salty liquid). Other local habits may work against good hydration, such as fattier foods, less fruit, alcohol, energy drinks, and coffee.
National Strength and Conditioning website
Advanced Sports Nutrition, Dan Benardot, PhD.
US Olympic Committee website
Center for Disease Control (CDC) website
American College of Sports Medicine website
Mayo Clinic website