Differences in ball flight parameters and in kinematics between two golf swing styles

This study compared golfers’ body and club kinematics with two swing styles (existing swings and The Optimal Performance Swing – TOPS), and two clubs (9- and 6-iron). The aims were to assess whether: (1) body kinematics associated with required TOPS positions and with performance, (2) club movements associated with ball direction and ball trajectory, (3) kinematics associated with low back pain – difference between thoracic and pelvic rotations at the top of the backswing (X-Factor); crunch range (difference between trail side lateral flexion at the top and at impact) and spinal forward tilt at address, would improve with the use of TOPS. Existing and TOPS swings were analyzed, and four TOPS training sessions were provided. Eleven Qualisys cameras collected kinematic data at 400 fps. Fifteen golfers (ages 18-73, handicaps +2 to -20), five females and ten males, participated. They performed ten shots per club, per swing style, and the five with the highest club speed were used for further analysis. Three 2 x 2 repeated measures multivariate analyses of variance were used to test the hypotheses. Significant main effects of TOPS across both clubs respectively were: a shallowing of club angle of approach (4.84 ± 1.9° vs 2.55 ± 2.21°) and a more in-to-out path (0.13 ± 4.3° vs 3.53 ± 4.33°), as well as a thorax that was more rotated to face away from target at address (4.71 ± 4.61° vs -18.66 ± 7.31°) and impact (9.72 ± 9.09° vs -3.15 ± 7.93°), and had less lead side lateral flexion at the top of the backswing 32.71 ± 5.46° vs 24.12 ± 5.53°). Three important variables associated with low back pain - X-Factor (-45.27 ± 14.55° vs -36.8 ± 8.48°), crunch range (52.22 ± 9.6° vs 42.12 ± 7.74°), and thorax forward tilt at address (36.01 ± 6.99° vs 30.47 ± 6.02°) - were all reduced with TOPS. TOPS could be used for approach shots with the iron clubs by golfers requiring better direction and trajectory of ball flight, consistency of club speed, and a reduction in some kinematics associated with low back pain.