Waist Exercise · Body Weight

Janda Sit-Up form demonstration - targeted for Abs Waist workouts

Janda Sit-Up

Named for physical therapist Vladimir Janda, this sit-up variation actively contracts the hamstrings by pulling the heels back into the floor during the movement, which is thought to reciprocally inhibit the hip flexors and force the abs to do more of the actual work. It's a more technical setup than a standard sit-up, and the hamstring tension has to be maintained throughout, not just at the start.

Go to the movement steps
Category
Waist
Equipment
Body Weight
Target
Abs

Exercise reference published by PlanWorkouts; see our editorial standards.

How to Do the Janda Sit-Up

  1. Lie on your back, knees bent and feet resting flat on the floor.
  2. Place your hands behind your head, letting your elbows point out to the sides.
  3. Contract your abs and curl your torso up off the floor until it reaches roughly a 45-degree angle.
  4. Pause briefly at the top of the curl, then lower your upper body back down slowly.
  5. Execute the desired number of reps with smooth cadence and consistent focus on the abs.

Quick Exercise Facts

Movement Type Movement reference
Equipment Body Weight
Main Muscle Abs
Supporting Muscles Lower Back

Practice and progression

Choose a short set of controlled repetitions or a manageable hold, following this movement's setup. End the set when you lose the demonstrated position. Build control before increasing repetitions, duration or resistance; holds, carries and moving drills need different prescriptions.

Technique & Form Tips

Focus on trunk flexion, rotation, or anti-movement stability as required by your specific variation. Maintain the suggested pelvic and spinal orientation to keep tension focused on the abdominal area throughout each repetition or hold.

Common Mistakes to Avoid

  • Copying the wrong trunk action: Follow the demonstrated movement. A held plank, rotation and crunch require different actions rather than the same repeated trunk curl.
  • Lower back arching: Keep the spine controlled to prevent the lower back from hyperextending under the load.
  • Excessive speed: Perform movements with deliberate control rather than relying on rapid, bouncing motions.

How to Breathe During This Exercise

Maintain a steady breathing rhythm during the effort.

Free Workout Plan Generator

Add the Janda Sit-Up to Your Custom Workout Routine

Build a personalized, science-backed workout plan matching your training goals, equipment access, and schedule.

Build Workout Plan →

Comfort and Control

Choose a load and range you can control. Stop if the movement causes pain. If discomfort persists, stop and ask a qualified professional about an appropriate exercise and range.

General guidance: Mayo Clinic on weight-training technique. Follow the specific movement steps above for this variation.

Muscles Worked

The Janda Sit-Up mainly targets your Abs, with your Hip Flexors helping support the movement, along with your Lower Back.

More Waist Exercises

More Abs Exercises

Equipment Alternatives

Don't have body weight? These target the same abs with different equipment.

FAQ

What muscles does the Janda Sit-Up work?
The Janda Sit-Up mainly works your abs. It also helps strengthen your hip flexors and lower back. Using good, smooth form makes sure you work the right muscles and avoid unnecessary strain on your joints.
What equipment do I need for the Janda Sit-Up?
You do the Janda Sit-Up with no equipment — just body weight. Make sure your equipment is set up safely before starting. If you work out at home or have limited gear, check out our alternative exercises below.
What form mistake should I watch for on the Janda Sit-Up?
One mistake to watch for is copying the wrong trunk action: Follow the demonstrated movement. A held plank, rotation and crunch require different actions rather than the same repeated trunk curl.. Use a comfortable range and a controlled return; reduce the load if you cannot maintain the demonstrated setup.
How many sets and reps should I perform on the Janda Sit-Up?
Use a short set of controlled repetitions, or a manageable hold when the movement is static. Stop when you cannot maintain the demonstrated position. Build control before adding duration, repetitions or resistance; the appropriate amount depends on the exercise and your experience.
What's a good alternative to the Janda Sit-Up?
The Assisted Hanging Knee Raise trains your abs with assisted and a similar movement pattern. Review its form guide before substituting it, since setup and range of motion can differ.
Community Q&A

Questions & Form Advice: Janda Sit-Up

Ask questions about joint angles, pain-free cues, or program substitutions.

Have a question about form cues, joint angles, or want to read discussions from other athletes?

Browse Community Discussions →