Ball Throwing Without a Ball: Pantomimed Motor Execution Primes the Imagination That an Object is Traveling the Required Distance

Practice Motions Performed During Preperformance Preparation Drive the Actual Motion of Golf Putting

Of the various types of preperformance preparatory behavior that are acquired during motor learning, the effect of a practice motion performed just prior to execution of an actual motion is not yet fully understood. Thus, the present study employed a golf putting task to investigate how a practice motion in the preparation phase would affect the accuracy of motor control in the execution phase and how proficiency would influence this relationship. To examine the impacts on kinematics and final ball position, the velocities of practice strokes made by tour professional and amateur golfers were experimentally manipulated in the following three conditions: the equal condition, which presented a target that was at the same distance during the practice strokes and the actual stroke; the confusing condition, which had two different distances during the practice and actual strokes; and the no condition, which did not include a practice stroke. The results, based on final ball position, indicated that practice strokes in the equal condition were linked with the highest accuracy levels during the actual stroke in both professionals and amateurs. In the confusing condition, regardless of skill level, the velocity of the actual stroke was influenced by a faster or slower stroke during the pre-shot phase. These relationships between the practice and actual strokes imply that the golfers effectively utilized kinesthetic information obtained during the practice strokes as a reference for the actual stroke. Furthermore, the differences in proficiency level indicated that the club head velocity of amateurs in the no condition was significantly faster than in the equal condition. Therefore, the present results imply that the role of a practice stroke may differ between professionals and amateurs.

Motor control of practice and actual strokes by professional and amateur golfers differ but feature a distance-dependent control strategy

We explored how practice and actual putting strokes differed between professionals and high-level golf amateurs, and how practice strokes reflected subtle differences in putting distances. We analysed swing amplitude, impact velocity, and acceleration profile of the club-head. The acceleration profiles showed that the motor control pattern of the practice stroke differed from that of the actual stroke. To clarify the effects of different putting distances on the practice stroke and to analyse how much the actual stroke could be explained by the practice stroke, we conducted individual regression analyses. The practice strokes of all participants could be divided into three strategies and five types by the coefficient of determination and the slope. This implies that the purpose of the practice stroke varied among golfers. Most golfers used the individual velocity criteria in their practice strokes, which resulted in different putting distances based on their criteria. Unexpectedly, we found no significant difference in skill level between professionals and high-level amateurs. The results of this study imply that the practice stroke does not duplicate the actual stroke, even for professional golfers with excellent skills. However, most high-level golfers adopted distance-dependent control strategies for slightly different putting distances.

Estimating Putting Outcomes in Golf: Experts Have a Better Sense of Distance

In putting, golfers require an internal forward sense of the causal relationship between putting actions and outcomes-a sense of distance-to decide appropriate impact intensity. As no previous work has shown such a cognitive ability in skilled golfers, we sought to quantify sense-of-distance skill differences between experts and novice golfers in both putting-swing consistency and accuracy of outcome estimation. We compared nine expert and nine novice golfers on putting-outcome estimation by having them putt a golf ball to a target located at three distances (1.2, 2.4, and 3.6 m), and then, after automatic closure of their electric-shutter spectacles immediately following putter impact with the ball, they gave their best estimate of where the ball stopped. We assessed outcome-estimation accuracy by calculating the absolute error between the stopped ball's actual and estimated positions. We also measured and analyzed putter head-swing movements during the task using a motion-capture system. Two-way, mixed-design analysis of variance tests revealed that expert golfers achieved both significantly lower variability in putter-head kinematics and higher accuracy at outcome estimation than the novices. Linear partial correlation analyses with target distance as the control variable tested the relationship between outcome-estimation performance and putter-head variability kinematic measurements. There were no significant correlations between them for experts and novices in separate databases, while medium correlations were found in a collective database. Thus, swing consistency and a sense of distance are independent skills that both account for putting expertise, and specific training is required for each to improve putting skills.