Section 8 Flashcards
“total chemical energy available to perform aerobic work”
aerobic capacity
“highest mitochondrial transformation of chemical energy per minute, measured as VO2 max”
maximal aerobic power
VO2 max
maximal oxygen uptake
Three energy systems
- ATP-CP system
- Glycogen to lactate system
- Oxidative system
Which energy system do we rely on during prolonged exercise?
O2 system/aerobic system
True or false?
Estimation of pure aerobic metabolism is impossible to perform
True, it is impossible to perform
What is the contribution of non-oxidative metabolism during moderate exercise intensity (12-14) min?
minimal, rely more on oxidative metabolism
How do we measure maximal aerobic power (VO2max)?
- all outperformance
- greater than 8 minutes
- fixed cadence (60 rpm, increase every 2 min)
- increasing workload
How do we test maximal aerobic power in children?
- same equipment
- cycle modifications (seat closer to pedals, lower pedal circumference, visual cadence)
Other options to measure VO2 max
- mechanical power during maximal effort (watts/watts/kg)
- extrapolate submaximal performance (PWC170)
- anaerobic threshold
Maximal VO2 test criteria
- max heart rate met = 220-age
- RER greater than 1.05
- VO2 plateau despite increased workload
RER
VCO2/VO2
What % of children reach VO2 plateau?
only 40-50% of children
%Fat and %carbs when RER = 1.00
0% Fat and 100% carb
%fat and %carbs when RER = 0.85
50% and 50%
%fat and %carbs when RER = 0.70
100% fat and 0% carbs
Growth-related adaptations in aerobic performance
- cardiovascular
- ventilatory
- economy of movement
Fick equation
VO2 = Q (Cao2 - Cvo2)
= HR x SV (Cao2 - Cvo2)
With growth, heart size_________ (increases or decreases)
increases
With growth, heart rate_________ (increases or decreases)
decreases
With growth, SV________ (increases or decreases)
increases
With growth, Q________ (increases or decreases)
increases
In young children, VO2_________ (increases/decreases) with exercise which _______ a-VO2 difference
increases, increases
At the same VO2 children: \_\_\_HR \_\_\_SV \_\_\_ Q >/< Cao2 - Cvo2
increased HR, decreased SV (smaller heart), same cardiac output, greater a-VO2 diff (children working closer to their maximum)
Ventilatory equivalent
Ve/VO2 (lower= more efficient)
Does ventilatory equivalent increase or decrease with age?
decrease
As we age, O2 uptake_________(increases/decreases) at the same workload
decreases
Children have a ________(higher/lower) cost of locomotion than young adults
higher
Children have a _______(lower/higher) metabolic reserve
lower, increases with age
Metabolic reserve
VO2 max - VO2 during submaximal exercise
Does co-contraction of muscles increase or decrease cost of locomotion?
increase, not efficient
Absolute submaximal aerobic power
- increases with age
- males 3x increase
- females 2x increase
Relative submaximal aerobic power
- watts/kg
- remains constant
Absolute VO2 max
- males increase to age 16
- females increase to age 13
- males greater than females
Relative VO2 max
- slight decrease with age (male and female)
Children’s lactate levels are _____(lower/higher) than adults during prolonged exercise
lower
Children’s RER value is ________ (lower/higher) than adults, which means they use more_______
lower, fats
Women burn more_______ and girls burn more______
carbs, fat
During moderate exercise, pre-adolescence relationship with SA is____
low
During moderate exercise, adolescence correlation with SA is
0.30-0.70
Relative VO2 maturity association
males- late-maturing greater VO2 max than ages 11-13
females- no maturity related difference
