Final answer:
The missing test for core muscular endurance is the side bridge test. It assesses the obliques and lateral stabilizers by maintaining a side plank position. Muscular endurance is linked to the proportion of SO muscle fibers and can be enhanced with endurance training.
Step-by-step explanation:
Physical therapists and orthopedic specialists employ the flexor endurance test, extensor endurance test, and the side bridge test as the three widely accepted methods to assess core endurance rather than strength. The flexor endurance test typically involves maintaining a specific flexed position, such as a sit-up hold, for as long as possible. The extensor endurance test assesses muscles in the back, requiring the individual to maintain an extended posture, like a back extension hold. The missing test in your question is the side bridge test, which focuses on the obliques and lateral stabilizers of the spine by holding a side plank position.
Muscular endurance is characterized by the ability of a muscle to sustain contractions or perform repeated movements over an extended period, and is related to the proportion of slow oxidative (SO) muscle fibers. These SO fibers are more prevalent in endurance athletes and in muscles responsible for maintaining posture. Regular endurance training can enhance these fibers, although excessive training can lead to overuse injuries.