ANATOMY

OBLIQUES

OBLIQUES

Rotation, Control, and Direction

The obliques are made up of two muscles on each side of the body:

  • Internal obliques

  • External obliques

They work as a pair.

The right and left obliques always work together to rotate, stabilize, and return the body to center. Because of this, it is impossible to completely isolate one oblique or completely shut the other off. Even in unilateral work, both sides are active.

Your job as an instructor is not to promise isolation.
Your job is to direct tension, name the focus, and coach intention.

HOW OBLIQUES WORK IN CLASS

Oblique workques are part of the core system, not separate from it.

In all oblique work, the following are also involved:

  • Rectus abdominis

  • Transverse abdominis

  • Hip flexors

  • Deep spinal stabilizers

Oblique work is essentially core work with direction.

Because obliques are short, flat muscles, they:

  • fatigue faster

  • do not require long sets to reach failure

  • respond strongly to tempo, pulses, and small ranges

UNILATERAL OBLIQUE WORK (WHAT TO SPEAK TO)

Since both obliques are always working, deciding which oblique to cue comes down to where the most tension is being created.

Consider:

  • direction of rotation or side bend

  • where the resistance or prop is placed

  • where the client feels the most effort

You should always cue the oblique that is under max tension, even though both will be felt.

PRACTICAL EXAMPLES

Supine Bicycle Oblique Crunch

  • Left internal oblique flexes to bring the right shoulder across midline

  • Right external oblique assists and works to control the return to center

If a ball is placed between the left knee and right elbow and pulsed:

  • Left internal oblique is under greater fatigue

  • Right external oblique is still active, but secondary

Cue the left oblique, while acknowledging that both sides are working.

Kneeling Side Bend with Cable (Right Hand Holding Cable)

  • Side bending left emphasizes the left internal oblique

  • Added resistance on the right increases load on the right external oblique

In this case:

  • Both sides are working hard

  • You may cue either, depending on where tension is greatest

The rule: cue the side working hardest, not the side you planned on paper.

INTERNAL OBLIQUES

Location

  • Deep to the external obliques (middle abdominal layer)

Fiber Direction

  • Run upward and inward (perpendicular to external obliques)

Primary Functions

  • Rotate trunk to the same side

  • Side bend to the same side

  • Assist spinal flexion

  • Support core stability and forceful exhalation

Example

  • Right internal oblique rotates torso to the right

  • Right rib cage bending toward right hip

EXTERNAL OBLIQUES

Location

  • Most superficial abdominal layer

Fiber Direction

  • Run downward and inward (“hands in pockets”)

Primary Functions

  • Rotate trunk to the opposite side

  • Side bend to the same side

  • Assist spinal flexion

  • Support posture and breathing

Example

  • Right external oblique rotates torso to the left

INSTRUCTOR STANDARD

You are responsible for:

  • understanding that both obliques always work together

  • cueing direction, not isolation

  • identifying where max tension lives

  • using props and resistance intentionally

  • keeping oblique work short, controlled, and precise

Oblique work should feel:

  • targeted

  • controlled

  • fatiguing

  • intentional

OBLIQUES — RUBRIC

Score each category 1–5
(1 = missing | 3 = inconsistent | 5 = excellent)

1) Anatomical Accuracy ____/5

Instructor correctly understands and explains internal vs external oblique function.

2) Directional Cueing ____/5

Cues clearly match the direction of rotation or side bend being performed.

3) Tension Awareness ____/5

Instructor cues the oblique under greatest tension, not just the “named” side.

4) Integration with Core ____/5

Core, breath, and stabilization are consistently layered into oblique work.

5) Programming Precision ____/5

Oblique work is appropriately short, controlled, and effective (no overworking).

6) Corrections + Coaching ____/5

Instructor recognizes compensation and redirects tension back into the obliques.

TOTAL: ____ /30

Notes:

Cue that worked well:

Opportunity to improve clarity or direction: