Mobility is the active, controlled range of motion at a joint. Distinct from flexibility (passive range), it requires strength and neural control at the extremes.
Mechanism: A joint mobilizes when the surrounding tissues yield AND the central nervous system permits load. Pure stretching addresses tissue length; mobility work addresses control.
Use case: Loaded end-range work (deep squats with weight, overhead pressing in full ROM, controlled articular rotations). 10 minutes daily compounds over years.
Caveats: Don't confuse mobility with flexibility. A gymnast is flexible. A gymnast under load is mobile.