Angular Kinematics at Play in the Golf Swing
Angular kinematics was the focus of this week’s readings, and several students used the golf swing to illustrate these principles at work in sport movement. To further investigate this topic and add to my understanding of Hamill and Knutzen’s (2009) text, I sought an article related to maximizing distance and accuracy in golf shots. Hume, Keogh, and Reid (2005) produced a thorough literature review on this topic derived from four review articles, 43 studies of original research, 27 proceedings from the World Scientific Congress of Golf, and a vast body of non-peer reviewed golf materials (including technical manuals and magazine articles) available both in print and online.
There is universal agreement among the literature that the displacement of a golf shot is a direct function of the linear velocity of the head of the club at impact. The linear velocity of the head of the club is a function of the angular velocity of the club head and the length of the arm-club lever at impact (Hume et al., 2005). As a result, maximal ball displacement is achieved through maximum angular club head velocity and/or arm-club lever length at impact.
In addition to this golf swing kinematics review, this article introduced me to two new concepts. The principle of weight shifting during the backswing and downswing is controversial among golf enthusiasts. Some profess that a lateral weight shift in the feet should follow the direction of club movement. One study demonstrated improved swing speed following a center of mass shift in the direction of intended ball flight (Hume et al., 2005). However, another study demonstrated that the hips and torso produce only a small fraction of the total linear velocity in the downswing (10%), lending some golf professionals to argue for a fixed base of support as opposed to a lateral shift in center of mass. Regardless, more studies are warranted to investigate the contributions of lateral weight shift to ball velocity at impact.
Another interesting topic discussed in this article was the effect of wrist-cocking on club head velocity. Three dimensional biomechanical analysis has revealed a greater degree of wrist cocking among professional golfers when the lead forearm is parallel to the ground. The degree of wrist cocking has been identified as the strongest determinant of club head velocity, producing an additional 9% increase in club velocity at impact and accounting for up to 60% of the variance in club velocity among golfers (Hume et al., 2005). Of course, the torque generated from the wrist cocking only translates to optimal club velocity and ball displacement if it is generated in the proper kinetic chain sequence. As 3-D analysis has confirmed, the optimal sequence is proximal to distal torque generation, with 5% contribution each from the spine and hips, 20% from the shoulders, and 70% from the wrist (Hume et al., 2005).
Hamill, J., & Knutzen, K. M. (2009). Biomechanical basis of human movement (3rd edition).
Baltimore, MD: Lippincott Williams & Wilkins.
Hume, P. A., Keogh, J., & Reid, D. (2005). The role of biomechanics in maximizing distance
and accuracy of golf shots. Sports Medicine, 35(5), 429-449.