The correction of pattern errors in golf swing: direct instruction feedback vs amplification of error feedback.

Aim: The aim of this study was to test the efficacy of an alternative teaching strategy called Method of Amplification of Error (MAE) and to compare the relative effectiveness of MAE to the traditional direct instruction method (DI) and to a no-feedback control condition (C). MAE is based on the assumption that subjects can learn to correct their movements through their mistakes (1). The rationale for the MAE is that giving a subject the opportunity to experience directly his/her own main error will trigger an autonomous searching strategy (2) that will in turn help him/her to improve performance. Methods: 15 golfers were assigned to one of three groups: DI feedback, MAE feedback and C without feedback, based on their handicap (H), (2 professional, 2 medium H and 1 high H for each group). During the training session each athlete performed 20 swings [7 swings pre- training (T0), 6 swings feedback training and 7 swings post-training (T1)]. After a week the athletes performed retention test (T2). Participants used their own driver and wore appropriate golf shoes. The feedback focused on the “main” error diagnosed as the incorrect position of the participant’s centre of mass projection (weight transfer). Kinematic outcomes were recorded with a motion analysis system (VICON 1.5.1, 8 cameras, 500Hz), a dedicated software (VICON Workstation 5.2) was also used for digitalization and reconstruction of the marker positions. Nonparametric statistical analysis was performed using SPSS version 16.; the Mann-Whitney test was conducted to assess significant differences between groups at three levels: T0, T1 and T2. Statistical significance was set at P≤0.05. Results: At baseline (T0) kinematic outcomes were similar between groups (P>0.05). At T1 and T2 MAE showed a greater improvement (p<0.05) than DI and C for club speed (T 1: 4.23%; -1.05%; 0.85%, T2: 5.11%; -1.02%; -0.28%, respectively), as well as for ball speed. In fact, MAE showed higher percentage change values than DI and C at T1 and T2 (4.21%; -5.33%; 1.8%; 8.27%, 0.72%; 1.6%, respectively). The same pattern was found for the duration of the swing phases: MAE showed a significantly decreased of tempo at T1 and T2 from the take away to the late backswing and from the early downswing to the ball contact (p<0.05). Discussion: Results showed that MAE rapidly improves motor performance in comparison with DI. The amplified error, besides providing the learner with new intrinsic feedback, stimulates the functions of perceptive categorization and the conceptual and symbolic elaboration of the received information, therefore improving his/her error detection capability. References 1 Milanese C et al. (2008). “Amplification of error”: a rapidly effective method for motor performance improvement. The Sport Psychol, 22, 164-174. 2. Newell KM et al. (1989). Search strategies and the acquisition of coordination. In Wallace (Ed), Perspectives on coordination 86-122.