• Fitness & Health
• Sport & Exercise Science
• Physical Education
• Strength & Conditioning
• Sports Medicine
• Sport Management
• Dance

Stages of learning new motor skills: Bernstein’s model

This is an excerpt from Life Span Motor Development 8th Edition With HKPropel Access by Kathleen M. Haywood & Nancy Getchell.

Fitts and Posner focused on perceptual and cognitive elements when describing stages of movement; their model emerged from the information processing theoretical perspective. By comparison, Bernstein (1967) described the stages of skill acquisition from a dynamical systems perspective, which focuses on the progression in solving the problem of degrees of freedom (Vereijken, van Emmerik, Whiting, and Newell, 1992; Vereijken, Whiting, and Beek, 1992). Within a human body, degrees of freedom are the number of independent variables (e.g., joints, muscles, motor units) that must be controlled when individuals complete a movement. For example, just think of two joints involved in an arm reach. The elbow has two degrees of freedom because it flexes and extends. The shoulder has six because it flexes, extends, abducts, adducts, rotates internally, and rotates externally. And this covers only the joints involved in the movement! Simply stated, in the process of acquiring the ability to make an efficient and effective movement, individuals must learn to coordinate actions with many different degrees of freedom.

Bernstein’s model also includes three stages of learning. In stage 1, individuals exhibit control through freezing degrees of freedom, or limiting the number of joints that move independently (figure 17.3 photo sequence 1). Look back at the developmental sequences in chapters 5, 6, and 7. Many of the early developmental levels provide evidence of freezing degrees of freedom. For example, in the arm action of throwing, new throwers limit their movement to flexion and extension of the elbow; in the leg action, they do not take a step. Both are examples of minimizing movement, of locking out—or freezing—nonessential joints to reduce the number of moving parts. The body functions more like one unit, and the action seems more singular than sequential.

Stage 2 represents releasing degrees of freedom (figure 17.3 photo sequence 2). After learners can successfully perform the basic motor skill, they no longer need to isolate body segments. Rather, they begin to release tightly locked joints to allow for more fluid movements and transfer of energy among the different segments. Movements become actions; that is, segments work together in a coordinated fashion. This can be seen within developmental sequences as well. In throwing, developmental level 2 of arm action adds movement at the shoulder, and developmental level 2 of leg action includes an ipsilateral step.

The final stage in Bernstein’s model is exploiting degrees of freedom (figure 17.3 photo sequence 3), in which learners begin to exploit reactive forces and passive dynamics of the body and environment (we discuss this in detail in relation to the principles of motion and stability in chapter 3). Learners reorganize degrees of freedom in a way that allows them to move efficiently and effectively by adjusting their bodies to the environment. In general, this occurs after learners have had many practice experiences over an extended period. For throwing, the most advanced developmental profile is a series of movements of many body segments perfectly timed to transfer momentum and create a whipping action.

KEY POINT Bernstein’s three-stage model focuses on controlling the degrees of freedom in an action to make a movement.

More Excerpts From Life Span Motor Development 8th Edition With HKPropel Access

---