Movement Analysis & Gait Practice Flashcards

These flashcards cover the fundamental concepts of movement analysis, muscle contractions, planes and axes of movement, kinetic chains, and the phases and mechanics of human gait.

What is an agonist?

The primary muscle producing the movement.

What is an antagonist?

The muscle opposing the movement.

What is a synergist?

A muscle that assists the agonist.

What is a stabiliser?

A muscle that prevents unwanted movement.

Can antagonists still be active during movement?

Yes. They may help control or stabilise the movement.

If a muscle is producing most of the movement, what role is it playing?

Agonist.

If a muscle assists the agonist but is not the primary mover, what role is it playing?

Synergist.

What is a concentric contraction?

The muscle shortens while producing force.

What is an eccentric contraction?

The muscle lengthens while producing force.

What is an isometric contraction?

The muscle produces force without changing length.

What is passive shortening?

The muscle shortens because the joint moves, not because it is actively contracting.

What is passive lengthening?

The muscle lengthens because the joint moves, not because it is actively contracting.

If gravity is helping the movement and the muscle is controlling it, what contraction is usually occurring?

Eccentric contraction.

If the muscle is actively creating the movement, what contraction is usually occurring?

Concentric contraction.

If a joint position is maintained without movement, what contraction is occurring?

Isometric contraction.

What does ROML stand for?

Range of Muscle Length.

What is the inner range of a muscle?

The shortest position of the muscle.

What is the mid range of a muscle?

The middle position of the muscle.

What is the outer range of a muscle?

The longest position of the muscle.

When a muscle shortens during movement, how does ROML usually change?

Outer → Mid or Mid → Inner.

When a muscle lengthens during movement, how does ROML usually change?

Inner → Mid or Mid → Outer.

During elbow flexion from fully straight to $90^\circ$, what is the ROML of biceps brachii?

Outer → Mid.

During elbow flexion from $90^\circ$ to full flexion, what is the ROML of biceps brachii?

Mid → Inner.

During elbow extension from flexed to straight, what is the ROML of biceps brachii?

Inner → Outer.

What plane divides the body into left and right halves?

Sagittal plane.

What movements occur in the sagittal plane?

Flexion and extension.

What axis is associated with the sagittal plane?

Mediolateral axis.

What plane divides the body into front and back?

Frontal plane.

What movements occur in the frontal plane?

Abduction and adduction.

What axis is associated with the frontal plane?

Anteroposterior axis.

What plane divides the body into upper and lower portions?

Transverse plane.

What movements occur in the transverse plane?

Rotation.

What axis is associated with the transverse plane?

Longitudinal axis.

Forearm pronation and supination occur in what plane and around what axis?

Transverse plane around a longitudinal axis.

What is an open kinetic chain movement?

A movement where the distal segment is free to move.

What is a closed kinetic chain movement?

A movement where the distal segment is fixed.

Is the swing phase of gait open or closed kinetic chain?

Open kinetic chain.

Is the stance phase of gait open or closed kinetic chain?

Closed kinetic chain.

Is kicking a ball open or closed kinetic chain?

Open kinetic chain.

Is a push-up open or closed kinetic chain?

Closed kinetic chain.

Is sit-to-stand open or closed kinetic chain?

Closed kinetic chain.

What are the two major phases of gait?

Stance phase and swing phase.

Approximately what percentage of the gait cycle is stance phase?

$60\%$.

Approximately what percentage of the gait cycle is swing phase?

$40\%$.

List the stance phase events in order.

Initial Contact → Loading Response → Midstance → Terminal Stance → Preswing.

List the swing phase events in order.

Initial Swing → Mid Swing → Terminal Swing.

When does tibia vertical occur?

After midstance and before terminal stance.

What happens to the tibia during midstance?

It moves forward over the foot.

Which muscle group controls forward tibial movement during midstance?

Plantarflexors (triceps surae).

What contraction are the plantarflexors performing during most of midstance?

Eccentric contraction.

Why do the plantarflexors contract eccentrically during midstance?

To control forward progression of the tibia.

What is the major difference between running and walking?

Running includes a flight phase.

What is a flight phase?

A period when neither foot is in contact with the ground.

What is step length?

The distance between successive initial contacts of opposite feet.

What is stride length?

The distance between successive initial contacts of the same foot.

When does maximum lateral trunk displacement occur during gait?

Midstance.

What effect does arm swing have during gait?

It reduces the energy cost of walking.

What happens to energy expenditure when arm swing is removed?

Energy expenditure increases.

What makes sit-to-stand easier: lowering or raising seat height?

Raising seat height.

Why does a higher seat make sit-to-stand easier?

Less force is required to lift the body.

Why does moving to the edge of the chair make sit-to-stand easier?

It helps move the centre of mass over the feet.

Why does placing the feet underneath the body make sit-to-stand easier?

It improves leverage and balance.

What is the most important movement required to bring the centre of mass forward before standing?

Forward trunk inclination.

Why is forward trunk inclination important before standing?

It moves the centre of mass over the base of support.

What is the first step when eliciting movement?

Observe spontaneous movement.

What is the general order of movement elicitation?

Observe → Request → Direct/Demonstrate → Enhance → Replace.

A person slowly lowers into a chair. What contraction are the quadriceps performing?

Eccentric contraction.

A person rises from a chair. What contraction are the quadriceps performing?

Concentric contraction.

A person holds a squat position. What contraction are the quadriceps performing?

Isometric contraction.

Shoulder abduction occurs in which plane and around which axis?

Frontal plane around an anteroposterior axis.

Shoulder flexion occurs in which plane and around which axis?

Sagittal plane around a mediolateral axis.

Trunk rotation occurs in which plane and around which axis?

Transverse plane around a longitudinal axis.

During gait, what is the role of the plantarflexors in midstance?

To control forward tibial progression and prevent the body from collapsing forward.

What is the triceps surae group?

Gastrocnemius, soleus and plantaris.

Which muscles are included in the triceps surae?

Gastrocnemius, soleus and plantaris.

Why is the stance phase considered a closed kinetic chain activity?

The foot is fixed on the ground.

Why is the swing phase considered an open kinetic chain activity?

The foot is free to move through space.

If a muscle is shortening but not producing the movement itself, what contraction type may be occurring?

Passive shortening.

If a muscle is lengthening but not actively controlling movement, what contraction type may be occurring?

Passive lengthening.

What is the quickest way to identify the agonist in movement analysis?

Determine which muscle is primarily responsible for creating the observed movement.