From the Bench · Explainer
Drag the scrubber (or hit play) to run one full gait cycle, and watch the body, the ground-reaction force, and the joint angles move together.
↑ Click a signal to send the dot along it.
One running stride runs from a foot's contact with the ground to that same foot's next contact. Each foot is only down for about the first third, the stance phase, and that is when the ground pushes back hard (the gold curve, peaking near 2.5× body weight). The rest is swing, and because the two legs are half a cycle apart there are moments where neither foot is down. The float phase that makes running, well, running. Most of my research lives inside that gold curve, measuring it honestly and estimating it from a sensor when there is no force plate around.
A stylized model for intuition, not a clinical dataset. Joint-angle and force curves are representative of distance running (rearfoot strike, ~3.3 m/s), smoothed for clarity.