Exam 4: Basic body composition Lecture

Question 1

body water is the ________ single component of the body

Answer 1

largest

Question 2

t/f approximately 60% of total body weight

Answer 2

t

Question 3

functions of water

1.
2.
3.
4.
5.

Answer 3

1. solvent, medium and substrate for chemical reactions
2. absorption and transport of nutrients
3. temperature regulation
4. excretion of waste products
5. lubricant and buffer for physical shock

Question 4

T/F Water is the most important nutrient and expect for minerals, the simplest nutrient

Answer 4

T

Question 5

T/F Electrolytes, part of the mineral class of nutrients discussed in the previous chapter,
have a myriad of physiological roles, some of which are serving source of energy,
synthesis of FFA

Answer 5

F

Question 6

T/F Since water is an essential nutrient, it cannot be produced by the body

Answer 6

→ false, we make
water in our body

Question 7

T/F Whole body sweat rate typically ranges from 0.5 to 2.0 liters (1.1-4.4 lbs) per hour but
can exceed 3 liters (6.6 lbs) per hour in approximately in 2% of athletes

Answer 7

T

Question 8

T/F In a review studies since 2008, Mcnaughton and others indicated that 300 mg per
kilogram body weight( 1 ounce for the average

Answer 8

F

Question 9

1000mg of salt provides 400mg of sodium → 40% of salt is sodium (Na), important to
know, 60% chloride (CI)

Question 10

-Intracellular water is

Answer 10

-Intracellular water is inside of a cell, intracellular fluid is 60-65% of total body water

Question 11

-Intercellular water is

Answer 11

-Intercellular water is water between the cells

Question 12

-Intravascular water is

Answer 12

-Intravascular water is water inside the blood vessels

Question 13

-Hematocrit

Answer 13

-Hematocrit (% packed blood volume), most is water inside of the cells

Question 14

why is hematocrit important?

Answer 14

-important for sports nutrition because sometimes the blood volume expands and you can tell by hematocrit going down and everything goes to the liver

Question 15

interstitial fluid

Answer 15

water in between cells

Question 16

The U.S. National Academies of Sciences recommend daily water intake of ____ liters for males and ____ liters for females,

Answer 16

3.7
2.7

Question 17

Only ____% of people meet these guidelines, according to NHANES data

Answer 17

40

Question 18

Water comes from _____ (about 80%) and ____ moisture (20%), with foods like fruits, vegetables, and meats contributing significant water content.

Answer 18

beverages
food

Question 19

fluid losses through ____, _____, _____, and _____

Answer 19

fluid losses through sweat, urine, respiration, and feces

Question 20

T/F High-protein diets can increase urine output, as proteins produce urea

Answer 20

T

Question 21

Can water be produced in the body?

Answer 21

yes, Metabolic processes also generate water. For instance, breaking down glucose produces metabolic water.

Question 22

t/f muscle and nonfat tissues hold more water than fat

Answer 22

t

Question 23

Extracellular Water: Accounts for

Answer 23

35–40% (14–17 liters)

Question 24

Extracellular Water: is subdivided into

Answer 24

Interstitial Water: Surrounds cells (8–9 liters).
Intravascular Water: Within blood vessels (3–4 liters).
Miscellaneous Compartments: Includes cerebrospinal fluid and others (1–3 liters).

Question 25

interstitial water is

Answer 25

surrounds the cells

Question 26

intravascular water is

Answer 26

within the blood vessels

Question 27

Proteins: Bind water in tissues, with plasma proteins like albumin helping maintain vascular water through c____ ________ ________.

Answer 27

Proteins: Bind water in tissues, with plasma proteins like albumin helping maintain vascular water through colloid oncotic pressure.

Question 28

the function of water “ lubricant and buffer for physical shock” is particularly important for football players because water can protect hearts and joints leading to less injury

Answer 28

t

Question 29

Intake/Input of water: majority of water comes from beverages and food

Answer 29

yes >90%

Question 30

less than 10% of water intake/input comes from metabolic reactions within the body

Answer 30

true

Question 31

the most variable water loss occurs by ____

Answer 31

sweat: type of exercise, location, environment…

Question 32

nonathletes have the most amount of water loss by ____

Answer 32

urination

Question 33

metabolic pathway that produces water?

Answer 33

ETC

Question 34

If losses exceed consumption.. What do we end up with?

Answer 34

DEHYDRATION

Question 35

Water accumulation→ end up with

Answer 35

edema

Question 36

What is hypervolemia?

Answer 36

Hypervolemia is a condition where your body has too much
fluid. Another name for hypervolemia is “fluid overload” or “volume overload.” Your body
is made up of 50% to 60% fluid, which includes water, blood and lymphatic fluid

Question 37

thirst is a symptom of ?

Answer 37

dehydration

Question 38

25% of our blood goes through our kidneys(blood lovers) every minute, so they can filter out the bad stuff and selectively reabsorb

Question 39

When does dehydration impair performance?

Answer 39

Some studies say Impair performance occurs with just 2%-3% of BW

Question 40

Running Times & Dehydration:

Answer 40

-sometimes you want to be around 1-2% less of body weight in a race because then you are lighter and beat the heavier people that have been topping off with fluids

Question 41

• studies say the fastest athletes in races are often more dehydrated than the slower athletes → less weight , more efficient ?

Question 42

sweat loss process

Answer 42

increases the temp of blood & osmolarity, osmolarity is how many particles are dissolved in solution, if you lose water→ everything in the blood becomes more concentrated and osmolarity is higher → higher osmolarity sends a signal to hypothalamus, hypothalamus is what senses this change in concentration (osmolarity in our blood) and sends signals that causes to feel things like thirst and tells the pituitary gland to send antidiuretic hormone (ADH) into the circulation , ADH prevents you from peeing, telling you to hold on to your water

Question 43

-It important for athletes when they first start to feel thirsty to start drinking some water

Question 44

Study: fluid intake of elite basketball players from the UK, they found out the players that drank later were never able to prevent dehydration or rehydrate during half time, they all failed to rehydrate because they let themselves get behind in the beginning of the game. The players that were able to maintain their hydration in the beginning of the game and throughout had the best performance!
-need to prevent the dehydration from the beginning to have optimal performance

Question 45

water influence on distance

Answer 45

They made them 2% dehydrated and then they measure their performance
~10% drop in plasma volume (1.9, 1.6, and 2.1% wt loss)
Results:
-1500m: .16 min slower when they were dehydrated, this wasn’t statistically different -5000m:1.13 min slower and this was statistically different
-10,000m: 2.13/3 min slower and this was statistically different
In conclusion, dehydration may not impair performance if the event is short enough but if the event is long enough it does impair performance

Question 46

Rating of perceived exertion figure, study

Answer 46

dehydration starts creeping in and feeling harder and harder at 80-120 mins→ rating of perceived exertion at 18 feels very hard at no fluid, then small fluid etc.
-another study: fluid + carbs combine were the fastest to complete the task overall
-when they got more fluid they were faster, they were able to do certain amount of work in less time vs placebo
-Overall, when you consume fluid to prevent dehydration, if it’s a task that will benefit from carbohydrates, you should consume carbs along with fluid too! Ex: sports drinks

Question 47

Humid weather:

Answer 47

Sweat does not evaporate readily
- Athlete “dripping” with sweat may be missing the cooling benefit
- Picture from book with the sun, heat stress, heat loss

Question 48

Study: 10 min mile → .50 sweating rate
- 1 kg of water =1 Liter of water
- What % dehydration 120# female athlete and loses 2.3 L sweating rate for 1 hour
exercise → 2.3kg/55kg of water= 4.2 % of dehydration→ leading to impair performance
and thirsty, For marathon: 11% dehydration for 2 hours can die from this
- Heat and humid a lot worse than cool and dry weather

Question 49

How can these problems be avoided in terms of dehydration, heat climates,heat illness?

Answer 49

If unavoidable, should build up tolerance (acclimation to the climate)
- Increases sweat production for better cooling( if you better sweater, better cooler) & decreases electrolyte loss
- Should be done safely (ie. gradually increase intensity & duration in heat)
- Usually takes about 1-2 weeks
- Restricting water does not aid in acclimation, may impair performance
2.Exercise during coolest part of day
3. Wear cool clothing
4.Drink cold fluids(with carbs & electrolytes if the event would benefit from carbs) →may want to hyperhydrate (consume extra fluid right before your performance to benefit)

Question 50

Why do heat and dehydration affect performance?

Answer 50

-Lower blood volume
- Decreased cardiac output
-Decreased work capacity
-Lower blood volume → poor thermoregulation→ heat injury→ decreased work capacity
2 main ways dehydration impairs performance: heat stress and decrease cardiac output→ both can impair performance

Question 51

why do heat and dehydration affect performance?

Answer 51

Study: more fluid restriction results in higher core body temperature, lower cardiac output,less fluid being consumed the lower the cardiac output, higher heart rate, and a lower stroke volume

Question 52

Heat Cramps:

Answer 52

-thrist, chills, goosebumps, clammy, throbbing heart beat, nausea -maybe muscle pain & spasms

Question 53

Heat Exhaustion:

Answer 53

-reduced sweating, dryness in mouth, weak/rapid pulse, headache, dizziness, fatigue -normal to elevated body temperature

Question 54

Heat Stroke:

Answer 54

-Very high temp. (up to 108+F)
-lack of sweat, dry/hot skin, visual problems, deafness,swollen tongue, nervousness, hallucinations, aggression, unsteady walking
-may collapse, lose consciousness, and convulse
-When you get to this point, you need immediate treatment because you have to cool the body right away first and then call the hospital

Question 55

cooling method

Answer 55

if you can get at least .15 degree celsius (optimal cooling) per min of cooling then the person will survive the heat issue

Question 56

treatment

Answer 56

Other treatments:
- Cool, rapidly absorbed fluids (2 cups of fluid for every pound lost)
- Cool or shaded environment
- none/little/light clothing

Question 57

fluids before exercise

Answer 57

4 hours

dark urine drink more

Question 58

before competition

Answer 58

euhydration status
4 hours before
5-7ml

Question 59

too mch cause

Answer 59

dilutional hyponatremia

Question 60

during competition

Answer 60

prevent excessive dehydration >2% loss

0.4-0.8l per hour

Na K

Question 61

after competition

Answer 61

fully replace fluids

1.5 l for kg body wieght loss