Home Core Workout Combo: Targeting Obliques and Serratus Anterior
Summary
Jeff Cavaliere of ATHLEAN-X presents a bodyweight core exercise that simultaneously targets the obliques and serratus anterior — two commonly neglected muscles that contribute to a visually defined, tapered core. He emphasizes that achieving a shredded midsection requires combining smart training with disciplined nutrition to reduce body fat enough to reveal muscular definition.
Key Points
- Abs alone are not enough for a visually impressive core — the obliques and serratus anterior are critical for the framed, tapered look
- The serratus anterior sits along the ribcage and adds muscular detail that frames the core from the sides
- Body fat reduction through nutrition is a prerequisite for seeing core definition regardless of training quality
- The featured exercise is equipment-free and can be done anywhere on the floor
- The movement combines two distinct actions — rotational and scapular — to hit both target muscles in a single rep
- Training muscles that work together naturally leads to better results than isolating them separately
- Tracking daily food intake is emphasized as essential to staying lean enough to see results
Exercise Details
Exercise: Cross-Body Knee Drive with Scapular Push
Target Muscles
- Obliques (primary — via rotational movement)
- Serratus anterior (primary — via scapular protraction)
- Abs (secondary — via spinal flexion)
Proper Form Cues
- Begin in a plank or push-up position
- Drive one knee across the body toward the opposite elbow — this bottom-up rotation engages the obliques
- Hold the contraction at the crossed position, then slide the knee up along the arm
- As the knee slides up, push the shoulder blade forward and around the body (scapular protraction) — this is the key movement that activates the serratus anterior
- Train both sides equally to hit the obliques on each flank
Key Movement Concepts
- Bottom-up rotation = oblique activation
- Scapular protraction (shoulder blades pushing forward and around) = serratus anterior activation
- The slide of the knee up the arm adds a spinal flexion component for additional ab engagement
Common Mistakes to Avoid
- Skipping the scapular push at the top of the movement — this is what separates the exercise from a standard mountain climber and is essential for serratus recruitment
- Neglecting one side of the body
- Relying solely on ab exercises and ignoring the obliques and serratus entirely
Sets/Reps
- No specific sets or reps were mentioned in the video