Learn the difference by looking.

A compressed foot usually tells a clear story: toes crowded together, the big toe drifting inward, the arch becoming passive, and the rest of the chain receiving a weaker signal from the ground.

A more natural foot also tells a clear story: toes that can splay, a big toe that can press, an arch that can load like a spring, and a foundation that gives the hips and core cleaner information.

Compensating movement can still look athletic. The body may perform, but force leaks into collapsed feet, rotated shins, unstable knees, anterior pelvic tilt, rounded shoulders, rib flare, or forward head position.

Clean movement is quieter. The foot presses, the ankle moves, the hip opens, the ribs counter-rotate, the shoulder answers, and force travels with less noise through the whole chain.

This comparison library should eventually hold photos, athlete examples, anatomy stills, and motion studies. The purpose is simple: make the invisible pattern visible enough that people can recognize it in themselves.