Chapter 4: Biomechanics

Question 1

Lever

Answer 1

A simple machine that has a rigid bar rotating around a point of rotation in order to multiply the effect of mechanical force or increase the distance force is applied.

Question 2

Fulcrum

Answer 2

The point of rotation

Question 3

Lever arm

Answer 3

The distance through which force is applied.

Question 4

Sticking point

Answer 4

The hardest point of the lift

Question 5

Law of Inertia Linear Movement

Answer 5

An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction (velocity) unless acted on by an external force.

Question 6

Law of Inertia Angular Movement

Answer 6

An object will maintain a constant angular velocity unless acted on by an external torque (moment).

Question 7

Law of Inertia

Answer 7

The resistance of an object to change its state of motion.

Question 8

Law of Acceleration

Answer 8

The Law of Acceleration forms the basis of quantifying training load.

Question 9

Law of Acceleration Formula

Answer 9

F = m * a

Question 10

Law of Acceleration Linear Movement

Answer 10

The linear acceleration of an object is produced by a force directly proportional to that force and inversely proportional to the object’s mass.

Question 11

Law of Acceleration Angular Movement

Answer 11

The angular acceleration of an object is produced by a torque (moment) directly proportional to that torque and inversely proportional to the object’s moment of inertia.

Question 12

Law of Reaction Linear Movement

Answer 12

For every force, there is a reaction force equal in magnitude and opposite in direction.

Question 13

Law of Reaction Angular Movement

Answer 13

For every torque (moment), there is a reaction torque (moment) equal in magnitude and opposite in direction

Question 14

Inertia

Answer 14

The resistance an object has

Question 15

Magnitude

Answer 15

The size referred to in a vector quantity

Question 16

Torque

Answer 16

The rotational effect of a force

Question 17

Mechanical Work equation

Answer 17

W = F X d, force times distance

Question 18

Angular work equation

Answer 18

Angular moment multiplied by angular displacement

Question 19

Positive work

Answer 19

The motive force and the movement direction are both the same.

Question 20

Negative work

Answer 20

The motive force and the movement direction are opposite.

Question 21

Power equation

Answer 21

Work divided by time

Question 22

Power

Answer 22

The rate at which force can be produced

Question 23

Antalgic gait abnormality

Answer 23

A self-protective result of injury to the pelvis, hip, knee, ankle, or foot

Question 24

Arthrogenic gait abnormality

Answer 24

Results from stiffness, laxity, or deformity

Question 25

Equinis gait abnormality

Answer 25

Inadequate dorsiflexion range

Question 26

Shot leg gait abnormality

Answer 26

Leg length difference

Question 27

Biomechanics

Answer 27

The branch of science that applies the mechanics’ principles to living organisms

Question 28

Total Caloric Expenditure

Answer 28

Metabolic measure of the volume of activity a person has completed.

Question 29

Active muscle force

Answer 29

The muscular contraction force created through the sliding filament theory.

Question 30

Passive muscle force

Answer 30

Passive refers to the fact that this force is generated not by the muscle itsell but by the application of an outside force to prestretch the muscle.

Question 31

Biomechanics response to the Antalgic gait

Answer 31

Stance phases of two limbs are not equal in time.

Question 32

Biomechanics response to the Arthrogenic gait

Answer 32

Unequal step lengths of the two limbs and circumduction of the affected limb.

Question 33

Biomechanics response to the Equinus gait

Answer 33

-Weight bearing on lateral edge of the foot
-Decreased stance time on affected side
-Pelvis and femur may be laterally rotated

Question 34

Biomechanics response to the Short leg gait

Answer 34

-Pelvic obliquity
-Exaggerated flexion of knee and hip of unaffected limb
-Hip “hiking” during swing phase for foot clearance
-Transverse plane movement of arm on one side

Question 35

Biomechanics

Answer 35

A discipline of science that combines physiology and physics in an effort to apply the laws of physics to living organisms.