ANAT101 Week Three

Which option(s) below are isotonic contractions?

• Isometric

• Eccentric

• Concentric

Answer explanation

Isotonic contractions are considered to be dynamic and involve a change in muscle length under tension

The change in length under tension can be either shortening (concentric) or lengthening (eccentric)

Which option matches the following definition, 'muscle length and joint angle does not change but muscle is working under tension'

• Isotonic

• Isometric

An 'agonist' can be contracting either isometrically, eccentrically, or concentrically

• True

• False

A muscle that has the functional role of antagonist must be contracting

• Isometrically

• Eccentrically

• Concentrically

• Not contracting

Match the following definitions with the functional roles provided

• Synergist

• Muscle that cancels out unwanted actions of agonist

• Antagonist

• Muscle producing the desired movement by contracting

• Agonist

• Muscle that must relax to allow the desired movement

• Stabiliser

• Muscle that fixes a body segment so the desired movement can occur

During the downward phase of a bodyweight squat, 'agonist' muscles are

• Eccentrically controlling the movement

• Concentrically producing the movement

• Isometrically stabilising the movement

• Not contracting ie. relaxing to allow the movement to be produced

Two joint muscles will have an increased requirement for synergism

• True

• False

Match the following definitions with the most appropriate term

• Passive insufficiency

• Connection between the tension a muscle fibre can produce and the length of sarcomeres in the fibre

• Length tension relationship

• Maximum shortening of muscle insufficient to produce full range of motion at both joints

• Active insufficiency

• Maximum length which is insufficient to allow for range of motion at both joints

Match the following images with their class of lever

• Third-class

• 
• Second-class

• 
• First-class

• 

Answer explanation

Tweezers would be an example of which class of lever?

• First-class

• Second-class

• Third-class