Chapter 4 - Biomechanical Principles of Training

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

First Law of Motion

Answer 5

To overcome an object’s inertia, a force must be applied. The objects’ inertia is proportional to its mass.

Question 6

Second Law of Motion

Answer 6

A force is proportional to the product of an object’s mass multiplied by its acceleration

Question 7

Third Law of Motion

Answer 7

A force cannot act alone on an object. A force is always met by another force.

Question 8

Inertia

Answer 8

The resistance an object has

Question 9

Force equation

Answer 9

F = M X A, mass times acceleration.

Question 10

Magnitude

Answer 10

The size referred to in a vector quantity

Question 11

Torque

Answer 11

The rotational effect of a force

Question 12

Mechanical Work equation

Answer 12

W = F X d, force times distance

Question 13

Angular work equation

Answer 13

Angular moment multiplied by angular displacement

Question 14

Positive work

Answer 14

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

Question 15

Negative work

Answer 15

The motive force and the movement direction are opposite.

Question 16

Power equation

Answer 16

Work divided by time

Question 17

Power

Answer 17

The rate at which force can be produced

Question 18

Antalgic gait abnormality

Answer 18

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

Question 19

Arthrogenic gait abnormality

Answer 19

Results from stiffness, laxity, or deformity

Question 20

Equinis gait abnormality

Answer 20

I nadequate dorsiflexion range

Question 21

Shot leg gait abnormality

Answer 21

Leg length difference

Question 22

Biomechanics

Answer 22

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

Question 23

Angular movement in the Law of Inertia

Answer 23

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

Question 24

Angular movement in the Law of Acceleration

Answer 24

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

Question 25

Angular movement in the Law of Reaction

Answer 25

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

Question 26

Total Caloric Expenditure

Answer 26

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

Question 27

Active muscle force

Answer 27

The muscular contraction force created through the sliding filament theory.

Question 28

Passive muscle force

Answer 28

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 29

Biomechanics response to the Antalgic gait

Answer 29

Stance phases of two limbs are not equal in time.

Question 30

Biomechanics response to the Arthrogenic gait

Answer 30

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

Question 31

Biomechanics response to the Equinus gait

Answer 31

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

Question 32

Biomechanics response to the Short leg gait

Answer 32

• 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