Chris McGrath by Chris McGrath
core training

For more on the anatomy and purpose of training, functional considerations including stabilization and reactive movement, and techniques to incorporate integrated core training, join ACE fitness expert Chris McGrath for our live one-hour webinar on Wednesday, Oct. 10 at 11 a.m. PST.

With perhaps the exception of aesthetic purposes, the most popular reason for training the core is "protection" or injury prevention—primarily for the back. We often hear the phrase, "The best way to protect your back is to strengthen your core." While this may not be untrue, it is not quite as simple as this statement suggests. If core training is important for injury prevention, especially for the back, we must be able to explain how core training helps and, conversely, why a "weak core" might lead to injuries. And exactly what do we mean by "weak core?"

To help break down the answers (of which there may be dozens of combinations), we must first have a fundamental understanding of the functionality of the core—and a clear concept of what "the core" actually is. At the risk of repeating many other core-related educational materials, here is a brief overview of the core:

  • The abdominal muscles are not the core. The abdominal muscles are some of the muscles that make up the core.
  • The core consists of a stabilization unit and a mobilization unit.
  • The stabilization unit consists of mostly muscles you can't see because they are deeper in the body.
  • In function, all of the abdominal muscles are designed as stabilizers, not as primary movers. (Yes, this includes the rectus abdominus and the external obliques.)
  • The spinal erector muscles are part of the stabilization unit.
  • The mobilization muscles are typically bigger muscles that move the body, but also influence pelvic and lumbar positioning and stability.
  • Planks and crunches do not constitute a balanced or comprehensive core-training workout.

What is a Weak Core?

"Weakness" is associated with a lack of strength, but is a lack of strength always associated with weak muscles? Absolutely not! Naturally, weak muscles can be a factor, but there are many individuals with no shortage of strong muscles (including "ripped" abdominal muscles) who still fall prey to back injuries—and not always during high-risk activities or exercises. So why might this happen? What else can "weak" mean?

In its simplest explanation, the stabilization unit of the core is responsible for two things—posture and timing—which are not mutually exclusive. When the stabilizers are irresponsible (i.e. not doing their job), poor postureresults. When our timing is irresponsible, poor posture results during activity. This presents as a form of "weakness." Individual muscles may be "strong," but can be simultaneously weak during functional activities. At the very least, poor timing affects efficiency and performance, but it also carries the risk of injury. In other words, the core must work in the right place, at the right time, to provide the stability needed to perform and protect.

Posture, which the core is largely responsible for, can be observed in two basic ways: statically (standing, sitting and/or balanced on a single leg) and dynamically (through movement). While static posture can be thought of as "neutral spine," or "standing tall," dynamic posture is not that simple. Dynamic posture requires control through stabilization, deceleration and/or reactivity. In some instances (typically under maximal loads), this might require a rigid and forceful "standing tall." But in other instances, maintaining a rigid and neutral posture will inhibit performance (as in swinging a baseball bat or tying one's shoe).

Observing dynamic posture is not exercise-specific—it is movement-specific, which  means the core needs to act differently depending on the activity performed, a fact that is rooted in one of the fundamental principles of exercise science—specificity. Therefore, while there may be some carryover, we should not assume floor-based exercises would have an automatic transfer to activities performed on our feet. Floor-based exercises can be good and may actually be the best place to start, but without integration with other activities, functional core strength may not be fully realized. 

Dynamic Core Posture

Given the countless movements performed in everyday life, it is helpful to define some basic patterns for observing dynamic core posture:

  • Under low loads (body weight)
  • Under moderate loads with endurance (either lighter weights or body weight with some momentum as in walking or jogging)
  • Under high loads (heavier weights and explosive activities)
  • Anti-rotation (resisting rotation when applied with a low to moderate force)
  • Bilateral stance movements (e.g., squatting)
  • Unilateral stance movements (e.g., stepping)
  • Split stance movements (e.g., lunging)

In line with specificity, just because the core works well on a bilateral movement doesn't guarantee it will work well in a split-stance movement. Additionally, it should not be assumed that low-load or low-intensity core control will predict high-intensity core function and visa-versa. High-load observations were included in the previous list, but should only be observed if the client is currently participating (or intends to participate) in high-load activities, sports or training. Also, don't be surprised if the high-intensity participant struggles with low-intensity core challenges.

Improving Timing

Low-intensity core stabilization should be viewed as the introductory phase for core training and timing, and may be accomplished through floor exercises from supine, prone and side-lying positions. Adding low-intensity perturbations to excite reactive responses in different planes can help prepare the core for low-grade dynamic stabilization, which is what the core encounters during everyday activities outside of exercise, sport and manual labor. This can also serve as an appropriate preparation for more progressive training. Finally, find ways to reactively stimulate the core through integrated exercises (while standing) and workouts. This will allow the core to adapt to higher demands in different situations and therefore offer better protection and better results.

It is worth repeating that timing and reactivity is enhanced through progressive training and is key to functionality. The ACE Integrated Fitness Training® (ACE IFT®) Model offers strategies for developing the core for function. While not all exercises in early stages seem terribly exciting, they serve as prerequisites to more advanced core-training practices—much like learning basic chords and scales on an instrument eventually allows the musician to play songs efficiently and effortlessly.

Nutrition Fundamentals

Translate nutrition knowledge
into client benefits.

Guide Clients