EX Phys Exam 3

Question 1

inability to dissipate excess heat

Answer 1

Heat Stress

Question 2

ability of body to maintain constant internal temperature

Answer 2

Thermoregulation

Question 3

Receptors in periphery & CNS detect

Answer 3

Temperature changes

Question 4

acts like thermostat

Answer 4

Hypothalamus

Question 5

Factors determining thermoregulatory stress

Answer 5

Ambient temperature
Relative humidity
Wind speed

Question 6

Relative humidity

Answer 6

% of water vapor held in air

Question 7

Plays a major role in heat loss
Affects our perception of thermal stress
When high (regardless of temperature, limits evaporation)

Answer 7

Humidity

Question 8

Mechanisms of Heat Loss

Answer 8

Convection
Conduction
Radiation
Evaporation

Question 9

Convection:

Answer 9

Air blows over surface of skin

Question 10

Conduction

Answer 10

Physical contact between 3 surfaces

Question 11

Radiation

Answer 11

Molecules in motion emit electromagnetic waves

-Infrared rays

Question 12

Evaporation

Answer 12

Water on skin turns to vapor

- Heat loss due to fluid evaporation

Question 13

As body temp rises sweat production_____

Answer 13

increases

Question 14

Sweat reaches _________ and _________

Answer 14

skin and evaporates

Question 15

Evaporation accounts for ______% of heat loss during exercise, but only ________% at rest.

Answer 15

80% during exercise

20% at rest

Question 16

Insensible water loss removes _____% with sweat

Answer 16

10%

Question 17

In heat stress, increase ______ and ______

Answer 17

Heart rate and cardiac output

Question 18

Redirects circulatory flow to periphery:

Answer 18

dissipate heat

cool blood

Question 19

Circulatory and Metabolic responses to heat stress:
body temp _________
oxygen uptake ______
Muscle lactate levels _______

Answer 19

Increases
increases
increases

Question 20

With heat stress sweating ______

Answer 20

Increases

Question 21

High volumes of sweet causes:
Blood volume to _________
____ of electrolytes
Release of _____ and ________

Answer 21

Decreases
Loss
Aldosterone and ADH

Question 22

Larger the body mass the greater ________

Answer 22

heat production

Question 23

Body fat insulates making heat loss _________

Answer 23

difficult

Question 24

Greater the fitness, the greater _________

Answer 24

Cardiac output

Question 25

Greater cardiac output improves ability to ______ heat.

Answer 25

dissipate

Question 26

Muscle cramps occur when one is exposed to ______

Answer 26

heat

Question 27

Heat cramps result from :

Answer 27

Dehydration Electrolyte imbalances Whole body sodium deficit Nueromuscular fatigue

Question 28

Heat cramps are triggered by intense _______

Answer 28

exercise

Question 29

Caused by failure to dissipate heat after intense exercise

Answer 29

Exertional Heat Stroke

Question 30

In exertional heat stroke core temp is elevates to > ____

Answer 30

104 F

Question 31

As heat increases, performance endurance _________

Answer 31

decreases

Question 32

Measures to ensure optimal performance (3)

Answer 32

Prior acclimation proper hydration proper conditioning

Question 33

Anaerobic and strength performance in heat depends on duration of ________ and duration of ________ exposure.

Answer 33

event | heat

Question 34

Longer events are ______ likely to affect performance

Answer 34

more

Question 35

Anaerobic and strength performance in heat stress can be improved by: (3)

Answer 35

Cooling methods hydration limit time of exposure in heat

Question 36

Physiological adaptation to an artificial environment

Answer 36

acclimation

Question 37

Physiological adaptation to a natural environment

Answer 37

acclimatization

Question 38

Time course of adaptations: - Cardiovascular: _ to _ days - Temperature regulation: _ to _ days - Conservation of Na: _ to _ days - All Adaptations: up to _ days

Answer 38

Cardiovascular: 1-5 days Temperature reg: 5-8 days Conservation of Na: 3-9 days All adaptations: up to 14 days

Question 39

Absence of exposure, adaptations lost in ___ to ___ weeks

Answer 39

2.5 to 5 weeks

Question 40

Adaptation occurring in Acclimation and Acclimatization: | - _______ core temperature at onset of sweating

Answer 40

Lower

Question 41

Adaptation occurring in Acclimation and Acclimatization: | - _______ heat loss via radiation and concoction

Answer 41

Increase

Question 42

Adaptation occurring in Acclimation and Acclimatization: | - _______ blood plasma

Answer 42

Increase

Question 43

Adaptation occurring in Acclimation and Acclimatization: | - ________ HR at specific workload.

Answer 43

Decrease

Question 44

Adaptation occurring in Acclimation and Acclimatization: | - ________ body-core temperature.

Answer 44

Decrease

Question 45

Adaptation occurring in Acclimation and Acclimatization: | - ________ O2 consumption at given workload.

Answer 45

Decrease

Question 46

Adaptation occurring in Acclimation and Acclimatization: | - _______ exercise economy.

Answer 46

Improved

Question 47

Sweating cools the body, but it _________ it.

Answer 47

Dehydrates