ch7

Question 1

why is water so critical to athletic performance

Answer 1

Loss of body water can be detrimental to both performance and health, as can excessive water consumption.
water. It is the most abundant sub- stance in the body, comprising approximately 60 percent of an average person’s body weight. Water provides the aque- ous medium for chemical reactions and other processes within cells, transports substances throughout the body, facili- tates thermoregulation (maintenance of body temperature), and is critical to most other physiological processes

Question 2

factors affecting body water content

Answer 2

• body size
• gender
• age
• body comp

Question 3

where is most water located in the body

Answer 3

1- intracellular water
2- extracellular water
3- interstitial fluid
4- plasma

Question 4

how does water go from ECF to ICF

Answer 4

hydrostatic and osmotic pressure

Question 5

hydrostatic pressure

Answer 5

difference in fluid pressure btw two areas
used by CV system to move blood
high pressure to low pressure

Question 6

sources of water

Answer 6

fluid consumption
food
cellular metabolism

Question 7

water is the most important

Answer 7

nutrient

Question 8

__% of adult body weight is water

Answer 8

60

Question 9

avenues of water loss

Answer 9

urination
defecation
sweating** up to 90% of water loss
insensible perspiration
breathing

Question 10

sodium intake and excretion

Answer 10

major ECF cation
excretion by the kidneys

Question 11

potassium intake

Answer 11

food, beverages or salt substitute
abundant in unprocessed foods

Question 12

recommended daily intake of potassium

Answer 12

4700mg

Question 13

hyperkalemia symptoms

Answer 13

muscle fatigue
weakness
paralysis
arrhythmias
diff breathing

Question 14

hypokalemia

Answer 14

increased bp
bone turnover
muscle weakness
cardiac arrhythmias

Question 15

potassium excretion

Answer 15

regulated by renal system
small amount loss in feces and sweat

Question 16

thermoregulation: where does the heat go

Answer 16

skin, body core
thermoreceptors in hypothalamus inc BF to skin and inc sweating

Question 17

body temmperature during exci dependent on

Answer 17

starting temp
exercise intensity
humidity
ambient temp

Question 18

exercise increases sweating why and influential factors

Answer 18

prevent excessive increase in body temp

• exci intensity and duration
• environmental factors
• clothing
• training status

Question 19

aerobic exci training improves thermoregulation via

Answer 19

inc blood vol
inc skin BF capacity
in sweat glands
earlier onset of sweating
inc sweat rate at given core temp

Question 20

exercise without fluid intake

Answer 20

no additional adaptations
progressive dehydration during exercise
hyperthermia and early onset of fatigue
inc risk of cramps and heat illness

Question 21

recommendations for heat acclimation

Answer 21

• repeated training in the heat
• Acclimatization >60 min/d with inc body core & skin temp, and stimulate sweating
• Train in same environment as competition
• Start >2 weeks (early adaptations w/i days, main physiological adaptations in 7 days)
• Follow hydration guidelines
• Consider external and internal cooling strategies

Question 22

why is replenishment during exercise difficult

Answer 22

• Voluntary dehydration
• Rate of fluid absorption is limited
• Intense exercise impedes gastric emptying
• Loss of 2–7% of bodyweight is common

Question 23

hypohydration

Answer 23

low hydration status
can lead to hypovolemia and hyperthermia

Question 24

hypovolemia

Answer 24

low blood volume
decrease BF and o2 delivery
affects thermoregulation and exercise performance

Question 25

hyperthermia

Answer 25

abnormally high body temp can lead to coma and death

Question 26

why can dehydration negatively affect performance

Answer 26

- dec BV - dec skin BF - dec sweat rate - dec heat dissipation - inc core temp - inc rate of muscle glycogen use

Question 27

what is the main electrolyte in sweat

Answer 27

Na

Question 28

light sweating

Answer 28

Na and Cl are reabsorbed in the tubules of sweat glands

Question 29

heavy sweating

Answer 29

Na and Cl are not reabsorbed fast enough

Question 30

exercise duration and Na

Answer 30

<2h no issue >2h may need Na during exci >4h may result in losses even in those who do not sweat heavily

Question 31

hyponatremia

Answer 31

- low blood sodium - can impair neural & muscular functioning. - commonly called "water intoxication." - more prevalent in endurance & ultra-endurance athletes. - excessive hyperhydration. - extensive sweating with only water replacement.

Question 32

muscle cramping caused by dehydration and electrolyte loss?

Answer 32

no, unfounded

Question 33

heat cramps

Answer 33

- Total body cramping when exercising in the heat - Sodium depletion, dehydration, muscle fatigue - May be a result of non-nutritional causes

Question 34

assessing and monitoring hydration status how

Answer 34

weight loss thirst urine color

Question 35

type, timing, and amount of fluid and electrolyte intake

Answer 35

- individualized plan - plan must be tested during training under various environmental conditions - plan may differ from training due tp stress of competition

Question 36

intake goals prior to training and performance

Answer 36

- be adequately hydrated before exercising - if not fully hydrated, rehydrating to the greatest extent possible - avoiding gastrointestinal upset - consuming carbohydrate, in appropriate

Question 37

see slides for rest of pp

Question 39

Daily fluid rec

Answer 39

Based on energy needs 1ml/kcal total energy expenditure

Question 40

Hydration strategies before exci if properly hydrated

Answer 40

Slow intake of fluids 5-10 ml/kg at least 4h before

Question 41

Hydration strategies if not properly hydrated

Answer 41

More aggressive approach 5-10 ml/kg at least 4h prior to+3-5ml/kg 2h prior Sodium can stimulate thirst

Question 42

Hyperhydration for enhanced performance pre-exci

Answer 42

Theory: expand blodd volume-> dec plasma osmolarity Experimental methods: drink ++ water or water -electrolytes solution 1-3 h prior to exci Iv infusion - conflicting results

Question 43

Glycerol loading

Answer 43

Allows for water storage before exci Loading regime: 1.2 g/kg 26ml water /kg 60-90min

Question 44

Potential adverse effects of glycerol loading

Answer 44

Temporary weight gain Gastrointestinal upset

Question 45

Intake during performance training and performance goals

Answer 45

Replace lost body water Slowing dehydration to the extent possible Avoiding overconsumption of water and other hypotonic fluids Replacing sodium if losses are large and rapid Consumming carbs if appropriate Avoiding gastrointestinal upset