The following blog post, adapted from NSCA and Jeffrey M. Willardson’s Developing the Core, details how core training exercises are classified as isolated or compound movements and how they help strengthen the core.

The core muscle involvement produces movement of the spine and might include movement of an adjacent joint such as hips or shoulders in an isolation movement. The abdominal crunch exercise is an example of an isolation movement. It has movement from the spine and no movement from the adjacent limbs. A compound movement is a movement where core activation produces limb movement against resistance or into the ground or other implement, or where the limbs, if fixed, move the torso through space. The compound movements also include upper body and lower body movement, as well as the muscles of the anatomic core for force generation.

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Isolated Workout Examples

Stability Ball Crunch:

Exercise Goal: Local Muscular Endurance
Type: Isolation
Difficulty: Easy
Breathing Recommendations: Long and Strong

Back Extension/Hyper Extension

Exercise Goal: Bracing and Spinal Stiffness
Type: Isolation
Difficulty: Moderate
Breathing Recommendations: Braced

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Compound Workout Examples

Cable Low/High Wood Chop

Exercise Goal: Local Muscular Endurance
Type: Compound Unilateral
Difficulty: Moderate
Breathing Recommendations: Long and Strong

Farmer’s Carry

Exercise Goal: Bracing and Spinal Stiffness
Type: Compound Bilateral
Difficulty: Moderate
Breathing Recommendations: Braced

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There are some situations in which unilateral movements can result in greater core muscle activity and performance outcomes than traditional core and compound movements. For example, when doing loaded carries, core muscle activity can be very high in all core muscles, with different patterns in either bilateral or unilateral variations. To achieve maximum results, a core training program should incorporate both bilateral and unilateral exercises. Many of the core exercises can be adapted by adding load, increasing velocity, or increasing time under tension for more challenge.

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Compound Unilateral Workouts 

Dead Bug

Exercise Goal: Bracing and Spinal Stiffness
Type: Compound Unilateral
Difficulty: Easy
Breathing Recommendations: Braced

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Compound Bilateral Examples: 

Medicine Ball Rotational Slam

Exercise Goal: Explosive Power and Speed
Type: Compound Unilateral
Difficulty: Moderate
Breathing Recommendations: Pulsed

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An exercise’s difficulty is determined by the number of moving joints, the skill required to complete it effectively, and the intrinsic loading. Bicycle crunch movement has lower difficulty because it requires very low skill. It only involves movement of the spine and hips, whereas a movement like a glute-ham raise is higher difficulty due to the much higher intrinsic loading, complexity and equipment required to set up, and movement occurring at the spine, hips, and knees.

Breathing during these core exercises can be broken into three main categories:

Long and Strong Breathing 

This type of breathing involves larger volumes of air on the inhale and exhale compared to normal breathing at rest. The main goal for this kind of breathing is to use respiration to increase muscle activity and intra-abdominal pressure during exercises that aim to increase local muscular endurance. To perform long and strong breathing, take a deep inhale, then brace the abs and exhale with some force, thinking of pushing the air out versus just letting it escape from the chest. Pushing the air out requires bracing the core muscles more than at rest and more than during the inhale portion. 

Braced Breathing 

In braced breathing, a person cannot reduce their core bracing during either inhalation or exhalation as a result of constant tension. When exercising to challenge spinal stability, the core muscles have to be engaged throughout the exercise, which can make breathing difficult. In order to perform braced breathing, you should inhale fully, then brace your core muscles around the volume that has been inhaled. When it comes to exhaling, limit the exhale to only half of the volume of air in the lungs, and try to maintain bracing throughout. Then inhale without releasing core muscle tension again. This type of breathing is useful, for example, during a barbell rollout exercise.

Pulsed Breathing 

Pulsed breathing technique is used to enhance speed and explosive power. Unlike more drawn-out exhales, this involves fast, sharp exhales. It is important to rapidly contract the core muscles to produce a rapid exhalation. As you breathe in, begin with a normal inhalation, and then, when you want to initiate a rapid or higher force movement, forcefully and quickly exhale a pulse of air, not the full volume of your lungs, and move as quickly as possible when your core muscles contract to push the air. An example of this would be a medicine ball underhand throw. Prepare yourself for the throw by inhaling and bracing your abs. At the moment of release, perform a pulsed exhalation.

Header photo by Jonathan Borba