Clubhead speed is not generated in the arms or the torso. It is generated by pushing against the earth. Force plates (like Swing Catalyst or Smart2Move) measure these invisible forces that dictate the kinematic sequence.
The Three Forces
1. Lateral Force
Side-to-side force. Peaks first in the transition (or late backswing). Responsible for the initial weight shift toward the target.
2. Rotational (Torque) Force
Twisting force against the ground. Peaks second. Created by pushing backward with the lead foot and forward with the trail foot.
3. Vertical Force
Straight up force. Peaks last (around lead arm parallel). The most strongly correlated force to extreme driver clubhead speed.
The Vertical Force Phenomenon
Long drive champions and elite tour players apply vertical force exceeding 200% of their body weight down into the lead leg during the downswing. The ground pushes back up, causing the lead leg to violently extend (snap straight), thrusting the lead hip up and back.
"If you want to swing faster, you must push harder against the ground. The arms are merely the delivery mechanism."