Biomechanics and Gait Analysis

Question 1

the study of the mechanics of a living body, especially of the forces exerted by muscles and gravity on the skeletal structure

Answer 1

biomechanics

Question 2

applied physics do not want to change the center of gravity of the animal

Answer 2

law 1 - change requires force

law 2 - force must be enough to accelerate the mass

law 3 - the ground must resist the push

Question 3

simplified explanation of the complexity of the horses back

Answer 3

bow and string theory

Question 4

the abdominal muscles contracting allow the back to lift

Answer 4

bow and string theory

Question 5

E. J. Slijper in 1946

Answer 5

bow and string theory

Question 6

bow and string model

Answer 6

by pulling on the string - tightening the abdominal muscles the back is able to flex and the hind legs can step under further resulting in lifted front end and lowered head and neck

Question 7

The extensors of the spine must be RELAXED to allow stretch and flexion

Answer 7

bow and string

Question 8

Richard Tucker 1964

Answer 8

expanded on the bow and string theory

longissimus dorsi - fascicles insert obliquely, down and forward

multifidus - oblique, down and backward

Question 9

these muscles allow for forward transmission of horizontal forces by compression

Answer 9

forward motion - Richard Tucker 1964

Question 10

vertical transmission of forces through rotary motion (resistance to gravity, balance control)

Answer 10

Tucker 1964

Question 11

demonstrated that the muscles are mirrored to each other and have to act in concert

Answer 11

James Rooney 1969

Question 12

the rider has a direct influence on the muscle groups activated

encouraged neutral balance

pilates idea - balance the work of the abdominal and back muscles to straighten the spine

Answer 12

james rooney 1969

Question 13

strength of riders core versus horses core

Answer 13

James Rooney 1969

Question 14

The creation of upward vertical forces through the spine was coordinated by muscles WITHOUT much movement of the vertebrae

increased stiffness of the muscles

decreased ROM of vertebral units

Answer 14

James Rooney

Question 15

Demonstrated that the abdominal muscles aren’t strong enough to influence the huge back muscles

Answer 15

James Rooney

Question 16

Function of the back muscles is to stabilize the vertebral column

Answer 16

Hans Carlson 1976

Question 17

Rather than increasing ROM, they function to prevent excessive ROM

Answer 17

Hans Carlson 1976

Question 18

confirmed and furthered by Leo Jeffcott in 1980

measured actual ROM of the joints in the vertebral column

Answer 18

Hans Carlson 1976

Question 19

Demonstrated that lateral bending was each vertebrae rotating around each other

Answer 19

Jean Marie Denoix 1999

Question 20

Researched the effect of the lowered neck on mobility of the spine

lowered neck results in stiffening of the lumbar vertebrae

Answer 20

Jean Marie Denoix

Question 21

lowered neck creates a stiff back

Answer 21

Jean Marie Denoix

Question 22

lumbar stiffness - increased work of the iliopsoas

Answer 22

iliopsoas muscle

Question 23

creates the illusion of lumbosacral mobility

increases injury risk - iliopsoas mm damage, lumbosacral damage, SI damage

Answer 23

lumbar stiffness

Question 24

transmission of horizontal forces results in

Answer 24

increased back mm tension

Question 25

lowering of neck/head increases

Answer 25

lumbar tension

Question 26

lateral bending is the result of

Answer 26

coordinated rotation of vertebrae

Question 27

absorption of impact (vertical forces) also results in

Answer 27

increased back mm tension

Question 28

equine design of potential, elastic, and kinetic energy - by having the majority of mass near the body (no mm distal to hock/carpus)

Answer 28

increases ROM increases elastic potential of ligaments/tendons elastic potential of rib cage

Question 29

equine design increases stride length without increasing

Answer 29

effort

Question 30

hairtie - stretches, holds the force and then contracts back together from stored energy

Answer 30

elastic energy

Question 31

assists the horse in overcoming gravity

Answer 31

elastic energy

Question 32

the potential energy stored when an object is stretched

Answer 32

elastic energy

Question 33

tendons can recoil faster than muscles can contract - allowing for higher jumping

Answer 33

elastic

Question 34

when a horse lands, full extension of fetlock - suspensory ligament acts as a cup so when it drops it creates the elastic recoil to not have the horse expend more energy

Answer 34

loading

Question 35

___ of horses weight is in the head/neck

Answer 35

10%

Question 36

eases teh work of the upper neck muscls

Answer 36

nuchal ligament

Question 37

nuchal ligament effore to keep neck in it’s position ___ at the walk ___ at the trot and canter

Answer 37

55% 32%-36%

Question 38

goals of the athlete

Answer 38

move weight bearing from front to rear rear has more pushing power change the rear from braking to pushing

Question 39

travels through the thoracolumbar spine if the back muscles do not act to absorb this thrust, the front legs are loaded

Answer 39

hindleg thrust

Question 40

increase duration of supporting phase step further under the body increased duration of deceleration increased absorption forces on the joitns

Answer 40

hindleg thrust

Question 41

the movements of the back directly influence the

Answer 41

head and neck position

Question 42

With a high head and neck position, the stride length and extension of the back are

Answer 42

significantly reduced

Question 43

downward/upward force is actually what maintains forward movement

Answer 43

propulsion

Question 44

why transitions strengthen

Answer 44

they require more push increasing speed requires more push the rest is downward force pushing up maintaining momentum forward - why impulsion is so important

Question 45

The forelegs produce the greatest percentage of upward vertical forces. __ of the vertical impulse is produced by the forelegs __ is produced by the hind legs

Answer 45

57% 43%

Question 46

causes of increased back stiffness

Answer 46

increased speed pushing on the bit rider’s weight lowered head/neck

Question 47

rider in propulsion adds increased pressure to the

Answer 47

extensor muscles

Question 48

breathing changes when under tension lack of abdominal effort increased ribcage and diaphragm breathing

Answer 48

abdominal muscles