Open-loop motor control executes a pre-programmed movement without using feedback to modify it during performance. Closed-loop motor control uses feedback during the movement, allowing errors to be detected and corrected.
How the Two Theories Work
In open-loop control, the performer selects and initiates an appropriate motor programme. Instructions are sent from the central nervous system to the muscles, but the movement is completed too quickly for sensory feedback to produce corrections while it is happening.
This suits fast, discrete, or ballistic movements, such as a javelin throw, golf strike, or tennis serve. Feedback can improve the next attempt.
In closed-loop control, sensory information returns through a feedback loop. The performer compares actual with intended movement, identifies error, and adjusts while the action continues. This suits slower, continuous movements, such as beam balancing, bicycle steering, or maintaining technique during a long-distance swim.
| Feature | Open-loop control | Closed-loop control |
|---|---|---|
| Feedback during movement | Not used | Used continuously |
| Movement type | Fast, discrete, ballistic | Slow or continuous |
| Error correction | Usually occurs after completion | Occurs during performance |
| Main advantage | Rapid execution | Greater accuracy and adaptability |
| Main limitation | Cannot correct unexpected errors during the action | Processing feedback takes time |
Closed-loop feedback may be intrinsic, from proprioceptors and sensory systems, or extrinsic, from a coach, video, or performance data. Extrinsic feedback often arrives after the movement, so influences later attempts.
A common misconception is that open-loop control involves no feedback at all. It means no feedback is used to alter the movement while it is being executed; feedback can still support future performance.
Exam Technique
For an IB SEHS comparison, define both theories, explain the timing of feedback, and apply each to a sporting example. Avoid classifying every skill as exclusively open- or closed-loop: phases of one performance may use different processes.