O southard and higgins racquetball forehand shot

o Southard and Higgins – racquetball forehand shot, “unfreezing” the joints
allow for an increase in racquet velocity at ball impact
 Changes in Altering an Old or Preferred Coordination Pattern : when confronted
with learning a new skill, we often determine that it resembles a skill we already
know how to perform, so we begin practicing it using movement characteristics
similar to those of the old skill
o We must overcome movement pattern biases to achieve the goal of the
new skill to be learned and performed
o It is possible to overcome these biases, but it requires a lot of practice
o ***Observable pattern of ‘ stability-instability-stability ’ characterizes the
transition between the production of the preferred movement pattern and
the production of the goal pattern
 Changes in Muscles Used to Perform the Skill : if practicing a skill results in
coordination changes, we should expect a related change in the muscles a person
uses while performing the skill; initially, muscles are used inappropriately
o More muscles than needed are often involved (inefficiency)
o The timing of the activation of the involved muscle groups is incorrect
o Change in muscle use reflects a reorganization of the motor control
system as that skill is acquired (degrees of freedom problem; reducing the
amount of work the system has to do)
 Changes in Energy Cost : practice should positively influence the energy-
efficiency of the performer
o Economy of movement refers to minimizing the energy cost of performing
a skill; beginners often expend too much energy while experts perform
more efficiently, with minimal energy expenditure
o Physiological energy (oxygen, caloric cost) and mechanical energy
(metabolic rate) will both decrease with experience
o Rate of perceived exertion (RPE) also decreases (the task feels easier for
experts than it does for beginners)
 Changes in Achieving the Kinematic Goals of the Skill : kinematic – spatial and
temporal features of the movements involved in performing a skill
 Displacement is the first; the spatial characteristics of a skill are generally the first
ones people successfully acquire
 Velocity is second, acceleration is third
 Changes in Visual Selective Attention : beginners typically look at too many
things, often leading them to direct their visual attention to inappropriate
environmental cues
 Changes in Conscious Attention Demands When Performing a Skill : acquisition
of automaticity through practice
 Changes in Error Detection and Correction Capability : improving the capability to
identify and correct one’s own movement errors either during (if the movement is
slow enough) or after the performance of the skill
 Changes in Brain Activity : as a motor skill becomes more automatic, the less the
cerebellum is needed in performance (seems to relate to adjusting movement

kinematics according to sensory input in order to produce an appropriate
movement)
**A Performer Characteristic That DOES NOT CHANGE Across the Stages of
Learning
