Get Shredded Obliques: The Correct Side Crunch Technique

Summary

Jeff Cavaliere of ATHLEAN-X explains how to develop visible, defined obliques — often described as “fish gill” lines along the sides of the torso. He emphasizes that everyone already has obliques, and the key to making them visible is a combination of proper nutrition and training the muscle correctly. The video focuses on fixing the commonly butchered Side Crunch exercise to maximize oblique activation.


Key Points

  • Everyone has obliques — genetics are not an excuse for their absence; the goal is to uncover and develop what’s already there
  • Nutrition is non-negotiable — without a proper diet, obliques will remain hidden regardless of how hard you train them
  • The oblique has two functions: spinal flexion and rotation toward the opposite side — both must be incorporated into training
  • The Side Crunch is an effective, equipment-free oblique exercise suitable for home training
  • Range of motion is smaller than most people think — the effective work happens at the top of the movement, not by swinging the elbow toward the hip
  • Quality of contraction matters more than distance traveled — reaching point B means nothing if the target muscle isn’t under proper muscular tension throughout the movement
  • Yanking on the neck is a common compensatory error that shifts stress away from the obliques and causes discomfort

Exercise Details

Side Crunch (with Rotational Component)

Target Muscles

Proper Form Cues

  • Focus the movement at the top of the range, not on achieving maximum distance
  • As you flex laterally, incorporate a slight rotation toward the opposite side to match the oblique’s natural rotational function
  • Perform the movement slowly and with control, emphasizing the contraction of the oblique at the peak
  • Keep the motion small and deliberate — the goal is muscle tension, not elbow-to-hip contact

Common Mistakes to Avoid

  • Trying to touch the elbow to the hip — this shifts focus away from the muscle
  • Lifting the entire torso excessively off the floor
  • Pulling or yanking on the neck to “shorten” the distance, which causes neck strain and removes tension from the obliques
  • Treating it as a pure lateral flexion movement without any rotational component

Sets/Reps

  • No specific sets or reps were mentioned in this video

Mentioned Concepts