The Assessment of Feedback Effort on the Performance of Serving and Reception Skills in Volleyball

Introduction In the past few decades, physical education instructors and sport coaches have been heavily influenced by the opinion that feedback provided to learners is necessary for learning and for the acquisition of motor skills (Bilodeau, 1966; Newell, 1974; Schmidt, 1991). Feedback is considered as an essential factor influencing motor learning because it assists the learner in evaluating his performance and in identifying his progress in achieving the ultimate goal. As indicated by Mustafa (1999), feedback is of two types: formative feedback and reinforcement feedback. Informative feedback gives the learner information needed to focus his efforts toward some selected goal, while reinforcement feedback strengthens motor responses to allow the learner to develop his performance. Therefore, feedback must be given for each learner to maximize performance (Mahjoub, 2002). The amount of feedback must be appropriate for the learner's abilities (e.g., age and level of learning). For example, young learners may not understand large amounts of information, so it is better to provide them with small amounts of feedback and it should be as a continuous process. Thus, the larger the amount of feedback the lesser is its effect (Schmidit & Wrisberg, 2000). The importance of feedback lies in correcting wrong responses and promoting correct responses by increasing repetition and by making the learning process more exciting (Aweis, 2001). Lack of feedback may leave no room for modifications to be made (error-correction) while the action (performance) is in progress and errors cannot be detected and modified until the performance is completed. Feedback is characterized as sensory information that provides the performer with information about the actual state of his performance. The sources of this information are either intrinsic or extrinsic as follows: 1. Intrinsic feedback is defined as sensory information that arises as a natural outcome of performing a motor task. Thus, intrinsic feedback is sometimes called inherent feedback. However, intrinsic feedback may come from sources outside the body (exteroceptors) or/and from within the body (interoceptors). Examples of exteroceptors include vision, auditory, and smell while interceptors include things related to skin, tendons, and muscles. 2. Extrinsic feedback is also referred to as enhanced feedback and or augmented feedback. Extrinsic feedback refers to information provided to the learner from a source outside the exterior--interioceptors. The main categories of extrinsic feedback include: (a) Knowledge of results which refers to extrinsic sources of information, usually verbal that tells learners something about the success of their actions with respect to the intended goal. In this situation, feedback may be redundant when the performer is told something he already knows about his action with regard to success or failure. On the other hand, non-redundant feedback is one in which the performer does not know the quality of his performance until certain evaluation criteria are given with regard to their performance (e.g., the decision of a panel of judges or results of an electronic distance measurement device reveals in points or distance). In such circumstances, intrinsic proprioceptors are of little value in indicating success or failure in performance. (b) Knowledge of performance which is called augmented feedback provides the performer with information regarding the pattern of their movements. For example, a coach may tell his athlete that his angle of take-off in the execution of the long jump was too vertical at the expense of the horizontal component of the take-off. It is important to note that knowledge of results feedback is associated with external sources of information that the performer can use in this next attempt at a novel task. Researchers believe that knowledge of result takes precedence over knowledge of performance. …