Dr. Sasho Mackenzie — attending Open Forum for the ninth consecutive year — shares the detailed case study of how he helped a PGA Tour player (Matt Fitzpatrick) increase club head speed from 112 to 121 mph using variable inertia speed training (The Stack), leading to a U.S. Open victory.
Sasho walks through his hierarchical physics model for club head speed, his player-first approach to intervention design, the longitudinal tracking of strokes gained off the tee, and the remarkable correlation between Stack training periods and on-course performance gains.