The ability of a joint and a muscle group to move through a full range of motion is referred to as a muscular endurance

False.

Explanation:

The ability of a joint and a muscle group to do a movement through an entire range of motion is referred to as flexibility and the ability of muscle to do work for a long time is referred to as muscular endurance.

The flexibility of joints and muscles can be improved by doing stretching exercises or yoga. Flexibility of muscles and joints reduce force on muscles and joints while working by equally distributing the force on body.  

Flexibility improves the working function of muscles and joints, therefore, a more flexible person performs some physical work easier than a less flexible person because his muscles and joints can do full range of motion. Therefore the statement is false.