muscular power

Question 1

muscular power

Answer 1

• force x distance / time
• or force x velocity
• uses anaerobic alactic system as a source for brief bursts of strength
• the ability of a muscle or muscle group to generate force as quickly as possible
• strength and power influence eachother

Question 2

contraction type and power

Answer 2

• max force output occurs during an isometric contraction
• peak power occurs at an “optimum” high velocity
• is in between force and velocity
• varies between people

Question 3

assessing muscular power

Answer 3

• use of force plates, load transducers, electronic goniometers, isokinetic dynamometry, and kinetic analysis
• force can be accurately measured as can the rate at which it is generated

Question 4

vertical jump

Answer 4

• performed at a max velocity (explosive) and requires moving body mass (kg) against gravity (9.81)
• body mass might not be enough of a load for maximum power

Question 5

various protocols for vertical jump test

Answer 5

• countermovement (one smooth motion vs strict form (1-2 sec pause before jump)
• 1 leg jump vs 2 legged for figure skater
• block jump

Question 6

how to measure vertical jump

Answer 6

• wall for jump and reach
• vertec
• jump mats
• optojump

Question 7

lewis equation for VJ

Answer 7

• uses vertical height and weight and can be plotted using a monogram
• leg power = 2.21 x body mass x square root of vertical jump (m)
• widely used but largely replaced by updated calculations

Question 8

sayers formula

Answer 8

• peak power = [60.7 x VJ] + [45.3 x BM] - 2055
• provides much higher VJ power scores than lewis
• more accurate description of peak power
• current formula endorsed by CSEP

Question 9

johnson and bahamonde formula

Answer 9

• takes into account height, and is used for counter movement umping
• power peak = 78.6 x vj =60.3 x mass -15.3 x height - 1,308

Question 10

reactive strength index

Answer 10

• a means to access “explosiveness” and account for the stretch shortening cycle during a performance or explosive power task
• measures explosiveness
• equipment of polymetric box of 30sm and a ground contact mat
• RSI = jump height / contact time
• contact time is how long you are on the ground = how quickly you generate power
• can compare to countermovement jump height to a static jump height

Question 11

horizontal long jump tests

Answer 11

• does not easily convert to power units as it has both vertical and horizontal components to test
• represented as absolute distance and compared to normative values instead of getting a power output
• popular in younger children or elite populations
• also impractical because you have to know an angle of takeoff

Question 12

seated med ball throw

Answer 12

• used in many athletic populations
• NHL uses a 4kg ball thrown as far as you can from a seated position
• other weights can be 6kg or 9kg
• ## get absolute distance instead of power output

Question 13

considerations of a seated med ball throw

Answer 13

• muscle isolation
• angle of throw (45 degrees ), optimizes distance
• brace the back because if you do not you lose power
• absolute distance is measured because you have a horizontal and vertical component

Question 14

isokinetic dynamometry

Answer 14

• accurate way to assess muscular power due to the isolation of certain muscles and joints
• accurately controls and measures velocity
• will actually get peak power
• very expensive and time consuming