Relationships among arm strength, wrist release, and joint torques during the golf downswing
Understanding the effects of body segment dynamics and interactions with strength boundaries on the coordination of the golf swing is crucial for improving swing performance and the design of effective training plans. We quantified kinematics of eight elite golfers performing normal golf swings, and simulated optimal solutions of the swing task with a series of mathematical models, each of which was based on a different number of body segments. We then compared these analytical solutions with the experimental data to determine the effect of segment number on the modeling and analysis of golf swings. Finally, we performed a series of optimizations involving modification of joint strength boundaries. We studied the effects of shoulder, elbow, and wrist strength boundaries on overall performance, wrist release timing, and segmental coordination. Empirical results showed that the elbow joint should not be excluded from models of the golf swing because elbow movements often become substantial. Analysis of experimental data and optimal model results revealed that wrist strength plays a major role in golf swing performance. Simulation of golf swings indicated that increased wrist strength, yielding a delay in the wrist release, is more important for improving clubhead speed at impact than are shoulder and elbow strengths. Also, delay in wrist release timing alone is not the only available means for improving performance, as the overall joint strength profile is also an important determinant of clubhead speed. This study thus reveals that individual kinematic and dynamic characteristics of the swing must be evaluated to determine productive or counter-productive actions and to improve overall golfing performance.