US Patent 11400332 Resistance band apparatus, method, and system

A system for selectively adjusting the fixed length of a single, retractable elastic body. The system enables control of the resistivity of the elastic body as well as a definitive determination of a level of force exerted against the single elastic body. The determined level of force is represented on an interface device embodied in a housing for the elastic body. The data associated with the determined level of force can be wirelessly communicated to other users' interface devices or smart devices for facilitating healthy competition between users.