Waist Exercise · Body Weight
Cocoons
- Category
- Waist
- Equipment
- Body Weight
- Target
- Abs
Biomechanical cues verified by the PlanWorkouts Science Review Board under CSCS editorial oversight; see our editorial standards.
The Cocoons is a targeted isolation waist movement designed to train the Abs with direct engagement of the Lower Back.
Trunk flexion, anti-extension, or anti-rotation targeting rectus abdominis and obliques. Requires posterior pelvic tilt to isolate abdominal fibers. Executing this with strict form maximizes muscle fiber recruitment while protecting joint structures.
Quick Exercise Facts
Target Muscle Activation
Cocoons curl the knees and torso toward each other simultaneously, working the abs and hip flexors together through a full-body crunch rather than isolating one end of the movement. It's a more demanding variation than a standard crunch since both the upper and lower body are moving at once. Keeping the motion slow and controlled, rather than rocking with momentum, is what actually taxes the abs instead of just swinging through the rep.
How to Do the Cocoons
- Lie on your back with your knees bent and both feet flat on the floor.
- Rest your hands behind your head, letting your elbows flare out to the sides.
- Contract your abs and curl your torso up off the floor slowly until it reaches roughly a 45-degree angle.
- Hold briefly at the top of the movement, then ease your torso back down to the start.
- Repeat for your planned rep target, maintaining clean technique and steady breathing on every repetition.
Recommended Sets & Reps by Training Goal
65–75% 1RM · 60s rest
50–60% 1RM · 30–45s rest
Controlled 3s eccentric · 60s rest
Biomechanical & Joint Load Cues
Trunk flexion, anti-extension, or anti-rotation targeting rectus abdominis and obliques. Requires posterior pelvic tilt to isolate abdominal fibers.
Common Mechanical Mistakes & Form Errors to Avoid
- Pulling on the Neck / Cervical Spine: Yanking the head forward with hands during crunches places excessive strain on cervical vertebrae without engaging the abs.
- Arching Lower Back Under Load: Allowing the lumbar spine to hyperextend during leg raises shifts work to the psoas hip flexors and pinches facet joints.
- Rushing Through Reps: Using fast bouncing tempo bypasses deep transverse abdominis engagement; slow reps with a full exhale build real core strength.
Proper Breathing Patterns & Core Engagement
Exhale completely during spinal flexion or maximal tension to maximize abdominal contraction; inhale on controlled return.
Add the Cocoons to Your Custom Workout Routine
Build a personalized, science-backed workout plan matching your training goals, equipment access, and schedule.
Injury Modification & Joint Safety
Individuals with lumbar disc herniations should prioritize isometric anti-extension (planks, dead bugs) over repetitive loaded spinal flexion. If joint irritation persists, immediately stop and substitute this movement with another exercise from the Waist exercises category.
Muscles Worked
The Cocoons primarily targets the Abs, with Hip Flexors as the primary synergist muscle group, along with the Lower Back.
More Waist Exercises
3/4 Sit-Up
45° Side Bend
Air Bike
Alternate Heel Touchers
Arm Slingers Hanging Bent Knee Legs
Arm Slingers Hanging Straight Legs
More Abs Exercises
Arms Overhead Full Sit-Up (male)
Assisted Hanging Knee Raise
Assisted Hanging Knee Raise With Throw Down
Assisted Lying Leg Raise With Lateral Throw Down
Assisted Lying Leg Raise With Throw Down
Assisted Motion Russian Twist
Equipment Alternatives
Don't have body weight? These target the same abs with different equipment.
Assisted Hanging Knee Raise
Assisted Motion Russian Twist
Band Alternating V-Up
Barbell Press Sit-Up
FAQ
- What muscles does the Cocoons work?
- The Cocoons primarily targets the abs as the primary agonist. Synergist assistance is provided by the hip flexors along with the lower back. Maintaining strict biomechanical alignment ensures maximal tension remains focused on the intended muscle fibers rather than shifting to surrounding stabilizer joints.
- What equipment do I need for the Cocoons?
- The Cocoons is performed using no equipment — just body weight. Ensure all equipment is securely positioned with collars or safety pins locked before loading working sets. If you train in a home gym or minimal setup, explore our equipment-free and resistance band alternatives below.
- What is the most common form mistake on the Cocoons?
- The most frequent error is pulling on the neck / cervical spine: Yanking the head forward with hands during crunches places excessive strain on cervical vertebrae without engaging the abs.. Controlling the 2 to 3-second eccentric lowering phase ensures maximal hypertrophic stimulus while shielding connective tissue.
- How many sets and reps should I perform on the Cocoons?
- For muscle growth and density, execute 3 to 4 working sets of 10 to 15 controlled repetitions with 60 seconds rest, emphasizing a deep stretch and deliberate peak contraction on every rep.
- What's a good alternative to the Cocoons?
- If you don't have access to the space or setup it needs, the Assisted Hanging Knee Raise targets the same abs using assisted instead. This alternative replicates the same joint angle and movement plane while allowing you to train effectively with different available gear. You can also substitute it seamlessly in our free Workout Plan Builder.