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Wet Your Whistle - Presentation Notes

“Wet Your Whistle” Presentation

Presenter Notes

Slide #1 – Wet Your Whistle

Slide #2 – Overview

The presentation will cover the following:

-The signs and symptoms of dehydration.

-The ways in which the body loses heat and cools itself.

-Why children/youth are at a greater risk.

-The signs and symptoms as well as the treatment for the three types of heat illnesses.

-Recommendations to avoid dehydration and heat illnesses

Slide #3 – Dehydration

Dehydration occurs when the body is low on fluids because an individual is not drinking enough fluids to replace what they are losing through sweating. Dehydration can lead to serious heat illness. But the good news is that it can be prevented through proper fluid replacement – drink, drink and drink!

When children and youth become dehydrated, the temperature in the core of their body increases. The core is where the body’s most important organs are located; heart, lungs, kidneys. If the core temperature rises to extreme levels, this can lead to serious health problems so every effort should be made to prevent exercise-related dehydration.

Slide #4 – Dehydration: Signs/Symptoms

The following can be signs and symptoms of dehydration:

-Body chills, even in a hot environment

-Muscle cramps, especially in the abdomen and legs

-Dark urine, very concentrated and low volume (i.e. not a lot of it)

-Feeling of general discomfort or “not feeling well”.

-Weakness, dizziness and headaches

-Heat sensations in the head and neck

-Irritability

-Feelings of nausea and vomitting

-Reduced sweating (i.e. not sweating as much as usual)

-Feelings of thirst

-Poor performance

Slide #5 – Ways the Body Loses Heat

The body’s most effective heat loss mechanism is the evaporation of sweat.

Slide #6 – Evaporation

When muscles become active, they release heat. This extra heat causes the inner temperature of the body to rise. The body then releases sweat on the skin’s surface which is then evaporated to cool the body.

Slide #7 – Factors affecting Evaporation

Three factors which affect the rate of evaporation:

1.Surface area exposed to the environment – how much skin is exposed to the air for evaporation to take place – if an athlete is wearing equipment or full body uniform, this reduces the surface area of the body that is exposed to the air and can reduce the amount of evaporation that takes place (i.e. football uniform)

2.Air current around the body – air moving around the body increases the rate at which sweat is evaporated

3.Temperature and relative humidity of the air – this is the factor that has the biggest impact on the rate and effectiveness of evaporation as a cooling mechanism

Slide #8 – Relative Humidity

Relative humidity is the percent of water found in the air compared to the total amount of water that could be carried by the air at a particular temperature.

Slide #9 – Relative Humidity & Dehydration

When the relative humidity is high, the water content of the air is higher and the air cannot absorb as much moisture. This can be compared to a wet sponge that cannot absorb anymore water. As a result, evaporation is not as effective as a method of cooling the body. Individuals are still losing a great deal of water, but they are not experiencing the cooling effects. This can lead to dehydration.

Slide #10 – Why Children/Youth are at a Greater Risk

The following is an overview of why children/youth are at a greater risk for dehydration when exercising:

1.Children/youth can lose a much higher volume of sweat when they are active on a hot and humid day. For example, during two hours of activity on a hot and humid day, children/youth can lose up to 1L or 4 cups of sweat.

2.Children/youth produce more heat per pound of body weight. When the body produces more heat, it has to sweat more to cool itself and as a result, is losing more water.

3.Children/youth are not as effective “sweaters” as adults. As a result, they are not as good at losing body heat through evaporation.

4.Children/youth do not have a high physiological drive to drink, so they are not motivated to drink enough to replace what they have lost through sweating.

5.Children/youth have a grater surface area: body mass ratio than adults. As a result, they have a greater heat gain from the environment on a hot day. If they are gaining more heat, they have a greater demand to cool off through sweating.

6.Children/youth take longer to adapt to hot, humid weather than adults. As a result, they will be sweating more to cool themselves off and will lose more water.

Slide #11 – Heat Illnesses

There are three types of heat illnesses:

1.Muscle cramping – least severe

2.Heat exhaustion

3.Heat stroke – most severe

Slide #12 – Muscle Cramps: Signs/Symptoms

Muscle cramps are painful, involuntary muscle contractions that usually occur in the legs and abdomen.

Muscle cramps are usually accompanied by excessive sweating and “saltiness” on the skin.

Muscle cramps can be caused by dehydration, the loss of too many electrolytes (especially sodium) or muscle fatigue.

Muscle cramps lead to poor performance.

Slide #13 – Muscle Cramps Treatment

The treatment for muscle cramps includes:

-Stopping the activity and resting in a cool and shaded area.

-Replacing lost fluids with drinks that contain sodium (an important electrolyte) including Allsport®, Gatorade®, Powerade®.

-Applying ice to the area that is cramping.

-Stretching or lightly massaging the area that is cramping.

-Positioning the athlete to increase blood flow to the area that is cramping. For example, if the abdomen is cramping, the athlete should raise their legs to direct blood flow to the abdomen area.

Slide #14 – Heat Exhaustion: Signs/Symptoms

Those with heat exhaustion will experience excessive sweating and will have pale, cold and clammy skin. They may experience weakness or fainting, and as well as nausea or vomitting.

Slide #15 – Heat Exhaustion Treament

If heat exhaustion is suspected, the participant should be moved to a cool and shaded area away from the heat source (i.e. out of direct sun). Tight clothing should be loosened and cool wet cloths should be applied directly to the skin to speed up the cooling process. Participant should sip sports drinks that contain electrolytes (Allsport®, Gatorade®, Powerade®), and their legs should be elevated to increase circulation.

Slide #16 – Heat Stroke: Signs/Symptoms

Heat stroke is the most severe and life threatening of the three types of heat illnesses. Those experiencing heat stroke will actually stop sweating and as a result will have hot and dry skin. Their core body temperature will be very high (40°C/104°F or higher), and could result in organ failure. Their pulse could be very rapid and they could lose consciousness.

Slide #17 – Heat Stroke Treatment

To treat someone for heat stroke, getting medical attention (i.e. calling 911) for the athlete is the number one priority. The vital signs (i.e. are they breathing, do they have a pulse) must be monitored and action must be taken accordingly (i.e. CPR). The participant should be moved to a cool, shaded area and the focus must be on lowering their body temperature. Cold water immersion or cold water spray is the preferred method of cooling as it will be much faster than applying cold, wet sponges/towels over the body.

Ice packs may also be placed on the groin, neck, head and armpits. However, do not apply ice directly to the skin. It is important not to give the participant anything by mouth (i.e. water) in case they vomit.