chapter 3 motor development

What is oppositional movement?

Sides of the body moving in different directions (such as right arm and left leg swinging forward at the same time).

What is cross lateral?

A term related to oppositional movement.

What is counter-movement?

A movement that involves a reaction or response to a previous movement.

What are the two principles within the larger field of biomechanics?

Motion and stability

What is known as the 'physics' of movement?

Motion and stability

According to what principles do developmental changes in movement occur?

Biomechanical principles

What does Newton's 1st Law state about inertia?

An object at rest stays at rest, and an object in motion stays in motion unless acted upon by a force.

What must we exert to move objects or ourselves according to Newton's 1st Law?

Force

What does more inertia mean for moving an object?

It's harder to move the object.

What is required to move an object with more inertia?

More force application is required.

What does Newton's Second Law state about acceleration?

Acceleration of an object is proportional to the force applied and inversely proportional to its mass.

In which direction does an object accelerate when force is applied?

The object will accelerate in the direction of the force.

What is the formula that relates force, mass, and acceleration?

F = m x a

How is acceleration related to force and mass according to Newton's Second Law?

Acceleration is equal to force divided by mass (a = F/m).

What happens to a soccer ball if you kick it harder?

It will go further.

What is an example of Newton's Second Law involving different objects?

Throwing a shot put versus a baseball at the same speed.

What limits how hard a person can throw an object?

A person can only throw as hard as they are physically capable.

What is Newton's Third Law?

To every action, there is an equal and opposite reaction.

What happens when you push on something?

It pushes back on you.

What is an example of Newton's Third Law in action?

Walking.

What would happen if there was no push back from the floor while walking?

You would fall through the floor.

How do you move up and forwards while walking?

By pushing down and back.

Why do toddlers have better balance while walking?

They mostly push up and not back.

What is the consequence of movement outside the plane of motion?

It is bad for performance.

What is the relationship between oppositional movements and directional force in walking?

When one leg goes forward, the opposite (contralateral) arm goes.

What is the first step in Cars' five-step process for observing and analyzing skills performance?

Observe the overall complete skill

What is the second step in Cars' five-step process for observing and analyzing skills performance?

Analyze each phase and its key elements

What is the third step in Cars' five-step process for observing and analyzing skills performance?

Use your knowledge of mechanics in your analysis

What is the fourth step in Cars' five-step process for observing and analyzing skills performance?

Select errors to be corrected

What is the fifth step in Cars' five-step process for observing and analyzing skills performance?

Decide on appropriate methods for the correction errors

What is the stability-mobility trade-off in new movers?

New movers adopt stability that maximizes stability and balance but hinders quick movement.

How do movers change their strategies as they develop?

With development and improvement in the ability to maintain upright posture during movement, movers shift to mobility strategies to move faster.

What happens to movement strategies as we get older?

As we get older, we tend to revert back to stability-focused movements.

What is stability?

The ability to resist movement.

How is stability applied in power lifting and golf?

Stability is crucial for performance.

What is balance?

The ability to maintain equilibrium.

How is balance used in wrestling and judo?

It helps maintain stability while disrupting opponents.

What is the trade-off associated with stability?

There is a mobility trade-off.

How do gymnasts perform movements?

They perform movements while in positions of relatively poor stability.

What developmental skills involve learning to absorb a force?

Ø Jumping down

Ø Falling

Ø Catching a "heavy object"

What must you do to make an object move?

Increase force application for a given time.

What must you do to make an object stop?

Increase time over which a given force is applied.

What effect does increasing rotational velocity have on rotating limbs and projected objects?

It allows you to swing it faster.

How can you increase the relative length of a rotating limb or projected object?

By fully extending it at release or contact.

What is the relationship between an object's linear velocity, rotational velocity, and radius of rotation?

An object's linear velocity equals its rotational velocity multiplied by the radius of rotation.

What is the definition of open kinetic chain movements?

Open kinetic chain movements involve the coordinated, proximal-to-distal transfer of energy.

How does energy transfer occur in open kinetic chain movements?

Large, proximal body segments initiate force, sequentially accelerating smaller, more distal segments.

What is the goal of optimal sequencing in open kinetic chain movements?

To achieve maximum terminal velocity or force.

Can you give examples of open kinetic chain movements?

Throwing a ball or kicking a leg.

What are open kinetic chain movements?

Physical activities where the distal segment of a limb moves freely in space.

What is the benefit of open kinetic chain movements?

They allow for greater joint movement and isolation of specific muscle groups.