Concept and Method of Performance Enhancement for Golfers

A good golf swing must have a repeatable swing plane, a stable axis of rotation, and high velocity at the club head. It requires neuromuscular coordination to make a simple swing plane, while increasing angular velocity of the golf dub. Muscle strength is required to mobilize several joints create pelvic rotation (i.e. horizontal plane) while stabilizing other joints. Lack of sufficient joint range of motion causes compensatory movements, resulting in unstable swing plane andfor potential injuries. For example, it requires nearly 180 degrees of neck rotation during a golf swing, which most of amateur golfers do not have. Therefore, a conditioning strategy for golfers must be designed to improve range of motion, muscle function, and neuromuscular coordination

STEP EXERCISE OR VERBAL AND VISUAL EXERCISE AFFECT COG, KINEMATICS AND PERFORMANCE DURING DECELERATION: RANDOMIZED CONTROLLED TRIAL

The purpose of this study is that investigate if step skill exercise or verbal and V i a l exercise affect the height of center of gravity (COG), kinematics and performance during deceleration. Sample size are 24 people (step skill exercise, n= 12; Verbal and visual exercise,n=12) . In the result, step skill exercise increased knee joint flexion angles in stop and deceleration. Furthermore step skill exercise decreased the height of COG only deceleration. However step skill exercise increased performance time ( reaction time) and had a negative impact

THE BLOMECHANICAL EFFECTS OF ANTICIPATION DURING A STOP-&-BACK RUN TASK TO SCREEN HIGHRISK ATHLETES FOR NONCONTACT ACL INJURY

The purpose of this study was to determine the role of anticipation on the lower extremity and trunk kinematics, and the height of the center of mass during a stop-&-back run task. Collegiate athletes (n=18) were recruited and completed three tasks; anticipated stop, unanticipated stop, and anticipated stop with a badminton net in front of their face. Three video cameras were used, and the trunk and extremity kinematics, and the height of center of mass (COM) for the second step before the complete stop (deceleration step) and the step of the complete stop (stopping step) were analyzed. At the initial contact of the deceleration step, the height of the COM was greater and the knee position was more posterior in the unanticipated condition than the other two conditions (p less than .05). The results showed the height of the COM was higher during unanticipated stop-&-back run task, which has important implications for future ACL injury screening

Dynamic three-dimensional shoulder kinematics in patients with massive rotator cuff tears: a comparison of patients with and without subscapularis tears

Background Massive rotator cuff tears (MRCTs) with subscapularis (SSC) tears cause severe shoulder dysfunction. In the present study, the influence of SSC tears on three-dimensional (3D) shoulder kinematics during scapular plane abduction in patients with MRCTs was examined. Methods This study included 15 patients who were divided into two groups: supraspinatus (SSP) and infraspinatus (ISP) tears with SSC tear (torn SSC group: 10 shoulders) or without SSC tear (intact SSC group: 5 shoulders). Single-plane fluoroscopic images during scapular plane elevation and computed tomography (CT)-derived 3D bone models were matched to the fluoroscopic images using two-dimensional (2D)/3D registration techniques. Changes in 3D kinematic results were compared. Results The humeral head center at the beginning of arm elevation was significantly higher in the torn SSC group than in the intact SSC group (1.8±3.4 mm vs. −1.1±1.6 mm, p<0.05). In the torn SSC group, the center of the humeral head migrated superiorly, then significantly downward at 60° arm elevation (p<0.05). In the intact SSC group, significant difference was not observed in the superior-inferior translation of the humeral head between the elevation angles. Conclusions In cases of MRCTs with a torn SSC, the center of the humeral head showed a superior translation at the initial phase of scapular plane abduction followed by inferior translation. These findings indicate the SSC muscle plays an important role in determining the dynamic stability of the glenohumeral joint in a superior-inferior direction in patients with MRCTs

POSITION-SPECIFIC DEFICIT OF JOINT POSITION SENSE IN ANKLES WITH CHRONIC FUNCTIONAL INSTABILITY

The present study was aimed to test a hypothesis that individuals with functional ankle instability (FAI) underestimate the joint angle at greater plantarflexion and inversion. Seventeen males with unilateral FAI and 17 controls (males without FAI) consented for participation in this IRB-approved, case-control study. Using a passive reproduction test, we assessed ankle joint position sense (JPS) for test positions between 30 and -10 degrees plantarflexion with an inclement of 10 degrees with or without 20° inversion at each plantarflexion angle. The constant error (CE) was defined as the value obtained by subtracting the true angle of a test position from the corresponding perceived angle. At plantarflexed and inverted test positions, the CE values were smaller in negative with greater in the FAI group than in the control group. That is, in the FAI group, the FAI group underestimated the true plantarflexion angle at combined 30° plantarflexion and 20° inversion. We conclude that the ankle with FAI underestimate the amount of plantarflexion, which increases the chance of reaching greater planterflexion and inversion than patients' intention at high risk situations of spraining such as landin