Definition
Movement variability is the natural fluctuation in how a movement is performed across repetitions. Some variability is healthy — too little indicates rigidity, too much indicates instability.
Why it matters
Contemporary movement science treats variability as informative, not merely error.
The Science
Optimal-variability theories show that adaptable systems maintain moderate variability. Loss of variability is associated with pathology in many domains.
The NSI Perspective
NSI treats variability as intelligent adaptability of the nervous system.
Clinical Implications
Rehabilitation that trains variability and adaptability (not just precision) produces better transfer to real life.
Practical Application
Do not chase perfect repetition. Adaptable movement is better than perfect movement.
References
- 1.Stergiou N, Decker LM. Human movement variability, nonlinear dynamics, and pathology: is there a connection? Hum Mov Sci. 2011;30(5):869–888.