Motor Control Models & Loops
What does “open-loop control” mean?
Movement is pre-planned and runs without feedback once initiated.
What is the main idea behind Schema Theory in motor control?
We store generalized rules or relationships between movement parameters and outcomes, allowing us to adapt skills to new situations.
Movement emerges from the interaction of what three elements?
Individual, Task, and Environment
Define kinematics vs kinetics.
Kinematics = description of motion; Kinetics = forces that cause motion.
What does QMD stand for?
Qualitative Movement Diagnosis
Define motor development.
Change in motor behavior over the lifespan influenced by biological and environmental factors.
What does “closed-loop control” rely on most?
Sensory feedback to make corrections during movement.
Name one invariant characteristic and one parameter of a GMP.
Invariant = relative timing / force / sequence Parameter = overall duration / muscles used
Give an example of a task constraint in sport.
Scoring rules, required equipment (e.g., must dribble in basketball)
In a 2nd-class lever, where is the load located?
Between the fulcrum and effort
List the 4 stages of QMD in order.
Preparation → Observation → Evaluation/Diagnosis → Intervention
List the 4 stages of motor development.
Reflexive → Voluntary → Proficient/Smooth → Refined/Automatic movement
Which part of a gymnast’s tumbling pass is open-loop vs closed-loop?
Take-off = open-loop; landing adjustments = closed-loop.
Why does practicing under many different conditions help learning?
It strengthens the schema rules that generate future movements.
Distinguish a regulatory vs non-regulatory environmental constraint.
Regulatory directly affects movement (surface, lighting); non-regulatory should not (crowd noise).
A sprinter pushes backward and downward into the track to move forward. Which Newton’s law and force vector direction best explain this?
Newton’s 3rd Law: for every action there’s an equal and opposite reaction; force vector directed backward and downward creates forward motion.
In which stage is feedback given to the performer?
Intervention stage
At what level of arousal is peak motor performance achieved?
Moderate arousal
In motor control, what is “feed-forward”?
A predictive command sent before movement begins (planning, not reacting)
How can movement variability benefit performance?
It offers flexibility to accomplish a task in multiple ways and adapt to perturbations.
What happens when a control parameter changes enough to destabilize a system?
The system self-organizes into a new attractor state (e.g., walk to run transition).
State Newton’s First Law of Motion.
An object stays at rest or in uniform motion unless acted on by a net external force.
Give one factor to consider during the preparation stage.
Knowing the performer, rules of the activity, and deciding what to observe.
What is the correct progression of skill acquisition in children?
Sensory systems → Gross motor → Fine motor → Self-care skills