As one of the major buzzwords in the fitness profession, does strengthening or “activating” the core actually reduces low back pain and hip pain? Does it also reduce the risk of injury and improve various athletic performance? If the answer to the first question is yes, what exercises are better in strengthening the core?
Research in this subject is quite murky since most studies have mixed methodologies and small sample sizes that cannot be applied to everyone, and nor do the effect sizes have much relevance to the real-life setting.1 Most claims fall back on anecdotes, “success” and “it works for me” stories, and observations (cause and effect) of the outcomes. For massage therapists who are also qualified to recommend or even teach exercise like a personal trainer or physical therapist, how can we make sense of what we hear, see, and read?
Most of the scientific literature agree that the core (or the lumbopelvic-hip complex) refers to the transverse abdominis, obliques, rectus abdominis, paraspinal and gluteal muscles, diaphragm, and pelvic floor muscles. They work together with the nervous system to stabilize the torso and spine for stability when moving.2
Many therapists and trainers think of the core from just the muscle perspective. However, the system is more integrated than that. Dr. Manohar Panjabi from the Department of Orthopaedics and Rehabilitation at Yale New Haven Hospital in New Haven, Connecticut, proposed a hypothetical model of how the core works, which includes three systems that interact together: passive, active, and neural control.3,4 The passive system consists of static tissues, including ligaments, joint capsules, the vertebrae, and intervertebral discs.
The passive subsystem comprises the static tissues, including vertebrae, intervertebral discs, ligaments, and joint capsules, as well as the passive properties of muscles. This system does not provide much stability outside of the end ranges of motion of a joint. In other words, it activates the most as a joint moves toward its end range of motion as tensile forces increase. Although it does not generate joint motions, the passive system—despite its apt name—“probably function in the vicinity of the neutral position as transducers (signal-producing devices) for measuring vertebral positions and motions.”3
The active subsystem—the musculature—is more commonly known as described earlier. Working with the passive system, it provides feedback to the nervous system and generates force. The amount of force each muscle generates depends on the amount of force the transducers in the tendons of the muscles produce.3
As the least acknowledged of the three in most fitness blogs, the neural control system ultimately decides how you move. This system consists of motor neurons, sensory neurons, the central nervous system, and the cerebral cortex, basal ganglia, and cerebellum of the brain that provide movement and feedback from the environment.3 Any dysfunction of any of the three systems can cause a chain reaction that influences pain and modification of movement (e.g limping after an ankle sprain).
While this model was proposed in the early 1990s, the basic anatomy and function of the core still stand today. However, research in the last 20 years have challenged—and changed—how we think about the core and applied exercises in relation to pain and movement.
24 massage & fitness magazine
Illustration: Dr. Johannes Sobotta
Illustration: OpenStax College
Illustration : Gray's Anatomy