EXAM 100 QUESTIONS AND CORRECT DETAILED
ANSWERS (VERIFIED ANSWERS) |ALREADY GRADED
A+
What are the fibre type changes when detraining? - ANSType IIa to IIb
Detraining/Conditioning - adaptations to the environment (recumbent position) - ANSDecrease
hydrostatic pressure to lower extremities
Elimination longitudinal compression long bones, spine
Reduced force all bones
Reduced energy expenditure
Bedrest observations - early work - ANSIncrease: Na+ and Ca++, decrease O2 uptake Effects
on: BMR, muscle atrophy, bone demineralisation, CHO metabolism
Plasma volume decreases with prolonged bedrest - Possible contributors for this? - ANSGauer-Henry
Reflex - headward shift of fluid produces transient increase in BV, compensatory loss of water and
sodium
ANP release
Decreased sensitivity of kidneys to fluid
Decrease plasma protein
Prolonged muscular activation can result in? - ANSFatigue
Define fatigue - ANSInability to maintain a given or expected power output or force production
Central fatigue? - ANSCentral command, motoneurons, conducive pathways to motor endplates
Peripheral fatigue - ANSPeripheral nervous system - excitation (contractile coupling), contractile
processes
,Muscle - sarcolemma, myofibril, sarcoplasmic reticulum
Why do some motor units fatigue before others? - ANSFibre type differences
Why could there be a change in motor unit activation after continued activity? - ANSAltered recruitment
pattern
Support from surrounding units not initially activated
Muscular contractions: Origins of fatigue - ANSLong-lasting endurance exercise, moderate intensity
- central fatigue, neurotransmitter, production (serotonin) or lack of (noradrenaline) - IL-6
- peripheral fatigue - substrate reduction
High intensity
- peripheral fatigue - metabolite accumulation, Na+/K+ imbalance
Sites of Fatigue - Excitation - ANSNeuromuscular junction, voltage gates Na+/K+ channels, sarcolemma
ttubules
Sites of Fatigue - Excitation-contraction coupling - ANST-tubules, Ca++ release, binding troponin
Sites of Fatigue - Contractile Processes - ANSBinding actin and myosin, cross-bridge formation, uptake
Ca++ into sarcoplasmic reticulum, relaxation role of ATP
Role of Metabolites in Fatigue - ANSIncreased [H+] decreases Ca++ sensitivity, binding of Ca++ to
troponin
Increased [Pi] also affects Ca++ activated tension
Increased [Mg++] inhibits Ca++ release from SR
Effect of Metabolic Factors in Fatigue - ANSATP necessary for Na+K+ pump and relaxation
ATP resynthesis dependent upon - PCr, glycogenolysis, glycolysis, aerobic metabolism CHO/fat
,IL-6 and Central Fatigue - ANSLarge increase with strenuous exercise and impairs athletic performance,
decreases endurance running
Transcription enhanced with glycogen depletion
Ammonia as a factor of Central Fatigue - ANSAssociated with toxicity when high - altered neuronal
excitability, extreme convulsions
Can deplete GABA and glutamate
Also stimulate PFK
Physiological differences between sexes: Men have higher... - ANSVO2max
Blood volume
Hct
Heart size
Better Hb and oxygen carrying capacity
Absolute strength
Greater muscle mass
VO2max differences between male and female. What does this mean for intensity and performance?
What happens to this difference once made relative to /kg fat free mass - ANSVO2max higher in males
than females
Given absolute intensity is higher %VO2max
Once made relative to /kg FFM, differences nearly disappear
Who has more % body mass (males vs females) and (normal/elite) - ANSMales < Females % body mass
Normal > elite
Hip width performance differences between males and females - ANSWider = less effective Made
relative, differences almost disappear
, Muscle Quality in Women - ANSLose more in legs than arms with age
Lose greater % with age than men
Start losing 20 years eariler than men
Less loading seen in which menstrual cycle phase - ANSFollicular - overcome by high CHO diet
Oestrogen effect on glucose availability - ANSIncreases (uptake in type 1 fibres)
Changes in Performance with Age - how much do they decrease? when is this accelerated? -
ANSPerformance decreases 6%/decade from about 30yrs, accelerates at 50yrs (greater rate for women)
Is there a particular sport that sees less of a performance decline with age? - ANSSwimming has a lower
rate of decline
Potential reason there is a smaller rate of decline for swimming performance deficits with age - ANSBody
type
Decrease drag
Increase buoyancy make more efficient and energetic limitations play greater role in long distance
swimming
More orthopaedic injuries with running limiting training volume in older athletes
Which physiological factors change with age? - ANSMax HR reduced
Cardiac output reduced
Body composition changes
What is the focus of the paper? - ANSUnderstand how the human body maintains itself and performs
work
Direct calorimetry measures energy utilisation through? - ANSHeat production
Indirect calorimetry measures energy utilisation through? - ANSRespiratory Gas exchange