© 2005 the mcgraw-hill companies, inc. all rights reserved. dangers of adverse environmental /...
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© 2005 The McGraw-Hill Companies, Inc. All rights reserved.
Dangers of Adverse Environmental / Thermal
ConditionsPE 236
Juan Cuevas, ATC
© 2005 The McGraw-Hill Companies, Inc. All rights reserved.
• Environmental _____ can adversely impact an athlete’s performance and pose serious health threats
• Areas of concern– _______________– _______________– Overexposure to the sun
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_______________
• Athletic trainers require knowledge and information concerning temperature, humidity and weather to adequately make decisions regarding environmental ___________
• Has caused a number of _____ over the years
• Must manage heat stress appropriately
• Hyperthermia = _______ in body temperature
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Heat Stress
• Extreme caution should be used when training in the heat (_________ could result heat stress)
• It is _________________• Athletes who train under these extreme conditions
are at risk• Physiologically the body will continue to function
if body temperature is maintained• Body must _____________ heat to maintain
homeostasis
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• Heat can be dissipated from the body through 4 mechanisms– Conduction (direct contact)– ____________ (contact with cool air or water
mass)– Radiation (heat generated from metabolism)– ___________ (sweat evaporating from the skin)
• Majority of body heat is dissipated through evaporation
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• Evaporative Heat Loss– ____________ allow water transport to surface– Evaporation of water takes heat with it– When radiant heat and environment
temperature are higher than body temperature, loss of heat through evaporation ________
– Air must be relatively ___________ for evaporation to occur
• relative humidity of 65% impairs evaporation• relative humidity of 75% stops evaporation
– ________________ can still occur in cold environment if body is unable to dissipate heat
• Caused by dehydration and inability to sweat
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Monitoring Heat Index• Heat, sunshine and humidity must be
monitored closely• Wet bulb globe temperature index (_______)
provides objective measure for determining precautions concerning participation in heat– WGBT incorporates different thermometer
readings• ___________ (standard mercury temperature)• ____________ (thermometer with wet gauze that is
swung around in air)
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– DBT and WBT can be measured with psychrometer (combines both thermometers)
• Wet bulb will be lower due to evaporation of water
– Ventilation is provided by whirling thermometer (sling psychrometer)
– Newer models utilize digital sensors
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© 2005 The McGraw-Hill Companies, Inc. All rights reserved.
Heat Illnesses
• Heat ___________ (heat collapse)– Associated with rapid fatigue and
________________, ________ in heat for long periods of time
– Caused by peripheral vasodilation, or pooling of _______ in extremities resulting in dizziness and fainting
– Treat by placing athlete in cool environment, consuming fluids and laying down
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• Heat Cramps– Painful muscle _______ (calf, abdominal) due to
excessive water loss and electrolyte imbalance– Occurs in individuals in good shape who
_____________ themselves– Treatment
• Prevent by consuming ______ fluids and maintaining electrolyte ________
• Treat with fluid ingestion, light stretching with ice ___________
• Return to play unlikely due to continued cramping
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• Heat _____________– Result of inadequate fluid _____________– Will exhibit signs of _______ sweating, _____
skin, mildly elevated temperature, dizziness, hyperventilation and ____ pulse
– May develop heat cramps or become faint/dizzy– Core temperature will be ~102o
– Performance may ________– Immediate treatment includes fluid ingestion
(intravenous replacement, ultimately), place in cool environment
© 2005 The McGraw-Hill Companies, Inc. All rights reserved.
© 2005 The McGraw-Hill Companies, Inc. All rights reserved.
• _____________– Serious _____-threatening condition, with unknown
specific cause– Characterized by sudden onset - sudden collapse, ______,
flushed _____ skin, minimal sweating, shallow breathing, _____ rapid pulse, and core temperature of > ______o F
– Temperature must be lowered within 45 minutes– Drastic measures must be taken to cool athlete
• Strip clothing• Sponge with cool water
• Transport to hospital immediately… ______!!!
© 2005 The McGraw-Hill Companies, Inc. All rights reserved.
© 2005 The McGraw-Hill Companies, Inc. All rights reserved.
Preventing Heat Illness• _____________ sense and precaution
– Consume fluids and ___________
• Fluid and __________________ Replacement– Single most important step taken by a coach to
minimize the chance of heat illnesses– Continual _________________ is critically important– Generally only 50% of fluid is ever replaced and should
therefore be replaced before, during, and after exercise
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– Fluid replacement should match ____________• Most effectively replaced at regular intervals (15 minutes)
– Time of stomach emptying is critical• Water is absorbed rapidly from intestine• Drink with 6% CHO is eliminated at the same rate if the individual is
hydrated• _________ drinks tend to empty rapidly and will not induce cramping• Drinks with caffeine and alcohol will promote _____________
– Hydration levels can be monitored via ________ color and volume
• Appropriate hydration = clear urine at normal or above-normal output level 60 minutes following exercise
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• Using Sports Drinks– _____ effective than just replacing fluids with water
– Flavoring results in increased desire to consume
– Replaces fluids and ______________
– Small amounts of _______ help in retention of water
– Different drinks have different nutrient levels
– Optimal CHO level is 14g per ___ ounces of water
– More CHO results in slower absorption
– Effective for both short term and endurance activities
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© 2005 The McGraw-Hill Companies, Inc. All rights reserved.
• Gradual Acclimatization– Most effective method of avoiding heat stress
– Involves becoming ___________ to heat and exercising in heat
– Early pre-season training and graded intensity changes are recommended with progressive exposure over __________ day period
– 80% of acclimatization can be achieved during first 5-6 days with 2 hour morning and _____________ practice sessions
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• Identifying Susceptible Individuals– Athletes with ________ muscle mass– ____________ athletes – Athlete with increased fluid loss– While slight differences exist, precautionary measures apply to
both males and females– Athletes consuming medications or ___________ may have
impaired sweating and may predispose them to injury
• Uniform Selection– Base on temperature and ___________– Dress for the weather and temperature– _________ rubberized suits
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• Weight Records– Keep track of before and after measures for first
___________– If increase in temperature and humidity occurs
during the season, weights should again be recorded
– A loss of ________-% = reduced blood volume and could be a health threat
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_________________
Most activity allows for adequate heat production (increased metabolism) and dissipation, allowing for sufficient functioning
• Impact on warm-up and “_____________”
• Temperature in conjunction with wind chill and dampness or wetness can increase chances of _______________
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• With __________ fatigue, rate of exercise begins to drop and rate of heat loss relative to heat production may shift – Results in impaired neuromuscular responses and
_____________
• Drop in core temp stimulates shivering but stops after temp drops below _________oF
• Death is imminent when temp falls below 77-85oF.
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Cold Disorders• Fluid replacement is critical even under
colder environmental conditions– Dehydration = decreased _________ = less
fluid available for tissue _____________
• May be useful to monitor weight of athletes training in cold temperatures
• While less common, injury/illness due to the cold still occur, particularly in ____________ type activities, winter sports and swimming in cold water
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• _____________– Apparel geared for weather to provide semitropical
microclimate for body and prevent ________– __________ and windproof fabrics that allow passage
of heat and sweat, and allow movement– __________ and adjusting them are key to
maintaining body temperature (during period of (in-activity)
– Inadequate clothing, improper warm-up and chill factor can lead to injury, frostbite, and/or minor ___________ problems
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Overexposure to _______-
• Precautions must be taken to protect athletes, coaches, athletic trainers and support staff
• ____________ Effects on Skin– Premature aging and skin ________ due to
ultraviolet exposure– Premature aging is characterized by ________,
cracking and inelasticity of the ________– Skin cancer is the most common malignant
tumor found in ________-
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• Using _____________– Can help prevent damaging effects of UV radiation– Sunscreen effectiveness is expressed as _____ (sun
protection factor)• Indicates how many times longer an individual can be exposed
to the sun with vs. without sunscreen before skin turns _____.• The _______ the susceptibility, the higher the SPF that should
be used
– Should be worn by ______, coaches, and athletic trainers who are outside a considerable amount, and/or have fair complexion, light hair, blue eyes, or skin that ____________
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– Sunscreen use is at its highest March - November but should be used year round (particularly between the hours of ________)
– It should be applied _______ minutes before exposure and re-applied after exposure to water, excess __________, rubbing skin with clothing or a towel