Development of a full-body computer model for golf biomechanics

Introduction. Computer simulation models permit the study of the complex interactions between biomechanical variables, yet their application to the scientific study of the golf swing is still in an early phase of development. Aim. The purpose of the present study was to validate a computer simulation full-body model of a golfer’s swing for driving clubs. Methods. Experimental data were collected in a laboratory for an elite male golfer (25 yrs, +1 handicap) who hit 24 shots, comprising of 8 trials using each of three drivers of different shaft length (46″/1.17m, 48″/1.22m & 50″/1.27m). The subject signed an informed consent and protocols followed guidelines approved by the University of Ulster research ethics committee. A 5-camera MAC™ system operating at 240Hz collected kinematic data which was subsequently used to drive the model utilising ADAMS software [1]. Additional skin markers were used for model validation. A large-scale musculoskeletal human model and parametric model of a driver were constructed (figure 1). Forward dynamics simulations were repeated 8 times for each of the 24 trials. Two commercially available launch monitors recorded experimental clubhead and launch conditions. Results & Discussion. There was a very high level of agreement (r=0.995) between the experimental kinematic data for the redundant markers and the predicted trajectory splines of the model, providing model kinematics validation. The model was capable of quantifying differences in upper torso and upper leg kinematics brought about by the different lengths of the clubs. There was also a high level of correlation (r=0.989) between the model predicted mean values for clubhead speed and the experimental values for each of the club lengths, both demonstrating increased clubhead velocity as club length increased. Muscle contraction force output by the model showed a significant difference (p<0.05) between driver simulations, demonstrating its capability to illustrate the link between gross muscle force production and club length, as evidenced by the increased force output for the longest shafted club. Conclusions & Implications. A large-scale musculoskeletal model has been developed that has the capacity to rapidly produce kinematic and kinetic results relating to variations in the golf swing when using clubs of different properties.