Unit 9: Anaerobic Performance

Question 1

Why is the yield of ATP through anaerobic energy turnover important for children

Answer 1

their activities involve bursts of energy expenditure
-the energy needs of children can not always be met by the O2 transport system and the oxidative properties of the working skeletal muscles

Question 2

What does anaerobic performance depend on

Answer 2

local characteristics of a skeletal muscle or muscle group

Question 3

What are the three components of anaerobic performance

Answer 3

Short term
intermediate
long term

Question 4

Instantaneous muscular engagements

Answer 4

characterized by an almost 100% anaerobiosis
-in a 3 second contraction, the anaerobic system meets nearly 100 of energy needs

Question 5

For how long does the anaerobic system contribute to maximal exercise

Answer 5

few seconds to about 3 min

Question 6

What % of ATP in a 90 sec max contraction comes from the anaerobic system

Answer 6

50%
-other 50% aerobic contribution

Question 7

What are the 4 primary energy sources that a child relies on

Answer 7

1. ATP stored in the resting muscle
2. Rapid phosphorylation of ADP to ATP through the creatine kinase enzyme pathway and the phosphocreatine pool
3. Anaerobic glycolysis from glycogen to lactate
4. Aerobic energy turnover using fatty acids, glucose, and glycogen as sources, together with oxygen

Question 8

What is the goal of all energy pathways

Answer 8

to produce ATP to support muscular contraction in the form of ADP + P + heat

Question 9

Use of ATP storage

Answer 9

-First and Fastest system (immediate source)
-Used in first 3 seconds of exercise

Question 10

Use of ATP and Creatine system

Answer 10

-second pathway
-quickly creates ATP to support muscle contrcation

Question 11

Glycolytic pathways

Answer 11

Converts glycogen, fatty acid, or glucose through more complex steps in metabolic pathways using O2
-more complicated processes take longer to turnover ATP

Question 12

How does the complexity and speed change across the different primary energy sources

Answer 12

increases in complexity and decreases in speed down the list of energy sources

Question 13

Determinants of anaerobic performance

Answer 13

related to body size (fat-free mass and muscle mass)
-age-associated and sex-associated variation more related to muscle mass differences than other factors

Question 14

What are the 10 Anaerobic performance tests

Answer 14

1. Margaria Step-running test
2. Vertical jump-Sargent test
3. Vertical Jump-force platform
4. Isokinetic single joint test
5. Force-velocity cycling test
6. Quebec 10-second and 90-second cycling test
7. Wingate Anaerobic test
8. Isokinetic cycling test
9. Sprinting-motorized treadmill
10. Sprinting-nonmotorized treadmill

Question 15

Margaria Step-Running Test

Answer 15

-First introduced in 1966, this test assesses peak mechanical power of a person who runs up the stairs at max speed
-Power (Kgm/s) = m(kg) x height (m) / t (sec)
-start 20 ft back go steps 3-6-9

Question 16

Advantages of the margaria step-running test

Answer 16

easy to administer
can be preformed in a school or gym

Question 17

Disadvantages of the margaria step-running test

Answer 17

-Performance is dependent on the skill of the participant
-participants may need to practice the skill several times to become proficient
-step-running requires many muscle groups, can’t isolate and measure just one

Question 18

Vertical Jump-Sargent Test

Answer 18

-First test to ever yield reliable information on short term maximal muscle performance
-participant crouches momentarily, swings arms and jumps as high as possible
-measured variable is the net vertical elevation (highest point reached minus standing)
-multiplies by body mass is proportional to the power generated at takeoff

Question 19

Vertical jump-Sargent test advantages

Answer 19

does not require equipment
can be performed at a school or gym
can be tested on both adults and children

Question 20

Vertical jump-Sargent test disadvantages

Answer 20

-more children younger than 7-8 years old do not perform the test adequately (basic movement patterns for the vertical jump is not yet fully developed)
- Among children in the 4th-7th grades (9-13) about 40% do not perform the vertical jump with mature pattern
-This inability may limit the utility of the vertical jump as a measure of anaerobic power

Question 21

Vertical jump-force platform

Answer 21

-participant takes off from a platform that electronically records forces
-by multiplying the vertical velocity at that instant, the mechanical power can be calculated

Question 22

Advantages of vertical jump-force platform

Answer 22

quick to complete

Question 23

Disadvantages of vertical jump-force platform

Answer 23

-The power produced by this test is only 50-60% of the peak power generated during the first 5-10 seconds of all out cycling
-Requires la equipment

Question 24

Isokinetic single joint test

Answer 24

-uses isokinetic dynamometer
-participant will preform repeated maximal extensions or flexions across a single joint
-mechanical power is calculated as the product of the predetermined angular velocity and the measure of highest torque in each extension or flexion
-variables such as peak power, total work and fatigue index can be calculated

Question 25

Force-Velocity Cycling Test

Answer 25

-test consists of several brief (5-7sec) cycling sprints on an ergometer
-each sprint is performed against a different braking force
-rationale for using several trials: mechanical power will be different at different braking forces
-only one force will yield actual peak power

Question 26

Force velocity cycling test graph axis

Answer 26

x- force, kg
y - velocity, rpm and power, watt

Question 27

Advantages of force-velocity cycling test

Answer 27

-the main asset of the force-velocity test is that it identifies the actual peak power
-peak power is less likely to occur with 1 single trial

Question 28

Disadvantages of force-velocity cycling test

Answer 28

-can take around 45min to complete several sprints with adequate rest periods in between

Question 29

Quebec 10-second test

Answer 29

-requires the participant to ride on a cycle ergometer all out for 10 seconds
-provides measure of total work output in 10-seconds
-has been used in children 9 years and older
-braking force set relative to body mass but is manually adjusted during the test so pedaling speed reaches about 10-16 m/sec
-reliability of test performance repeated within 7 days is above 0.95

Question 30

Quebec 90-second test

Answer 30

-requires a ride to exhaustion
-has been used in boys and girls 10 years old & above
-braking forces set relative to body mass
-participant must pedal maximally for 90-seconds
-only one trial is given
-reproducibility of the test within 7days is 0.96

Question 31

Wingate anaerobic test

Answer 31

-developed in the mid 1970s at the wingate institute in Israel
-most commonly used test for assessment of short term and medium term anaerobic performance
-30 sec cycling or arm cranking at max speed at a predetermined braking force
-force high enough to induce fatigue within several seconds
-power is calculated periodically or continuously (force x velocity)
-indices of performance are peak power (highest power achieved at any 3 sec period) and mean power (average power throughout 30-sec)

Question 32

Disadvantage of the wingate test

Answer 32

lack of an easy way to determine the optimal braking force that would yield the highest possible power

Question 33

Isokinetic Cycling test

Answer 33

requires a constant cycling velocity, where the changes in power are driven from the changes in the force exerted on the pedals
-test offers research opportunities regarding muscle contractibility and fatigability

Question 34

Sprinting- Motorized treadmill

Answer 34

-The time that a person can keep sprinting on a motorized treadmill has been used as an index of intermediate-term anaerobic performance
-can also calculate the mechanical power or work performance based on body mass, running velocity, treadmill incline
-test based on several assumptions that have not been validated
-used with children and adults to estimate “total-body” anaerobic performance
-tends to evoke fear of falling causing early termination
-use harness to prevent falling

Question 35

Sprinting - non-motorized treadmill

Answer 35

-Treadmill driven by the walking or running person
-participant tethered with a cable around waist
-horizontal cable connected to sensor to monitor horizontal traction forces and vertical displacement
-running velocity is determined by treadmill
-indices of performance include maximal velocity, peak power, mean power over a predetermined time, kinetic and potential energy, and the time to exhaustion
-little research on the sustainability of these treadmills with children

Question 36

Recovery after anaerobic exercise in children

Answer 36

• Researchers have long had the impression that children recover faster than adults after a strenuous physical task
  -Experiment on rate of recovery after wingate test boys (9-12 years) vs men (19-23 years) investigated % peak power recovery and H+ ion accumulation

Question 37

Age differences in % peak power recovery

Answer 37

the time needed in between attempting another wingate test - and what % they could preform
-boys could perform 100% after 2 min recover while men could only perform 80% at that point
-10 min recovery for men to be able to perform 100%