Tuck-Up
The tuck-up bridges the gap between a hollow hold and a full V-up: from a long hollow shape lying on your back, you crunch up and pull the knees to the chest at the same time, meeting over the hips. It trains both ends of the rectus abdominis to fire together and teaches the compression that harder skills like the V-sit demand. It is a versatile core builder for trainees who own the hollow hold and want a moving progression.
- Equipment
- Body Weight
- Body part
- Abs
- Type
- Strength
- Browse by muscle
- Upper Rectus Abdominals, Lower Rectus Abdominals
- Browse by movement
- Spinal Flexion
- Target
- Upper Rectus Abdominals, Lower Rectus Abdominals
- Secondary
- Rectus Femoris, Abdominal External Oblique
- Tertiary
- Adductor Longus, Erector Spinae
How to do it
- 1
Lie on your back with the arms overhead and legs straight in a long hollow shape.
- 2
Press the lower back into the floor and brace the core.
- 3
Simultaneously crunch the torso up and draw the knees toward the chest.
- 4
Reach the hands past the shins as the body folds over the hips at the top.
- 5
Extend back out under control to the long hollow position without arching.
- 6
Repeat for reps, keeping the lower back flat the entire time.
Tips
- Keep the low back pressed down as you extend; letting it arch takes the abs out of the work.
- Move under control on the way out rather than flopping flat between reps.
- Exhale hard as you fold up to help the abs contract fully at the top.
Variations
Common mistakes
- The knees do all the travelling while the shoulder blades stay pinned to the floor, which turns the tuck-up into a reverse crunch and leaves the top half of the abs out of it.
- The hands reach for the shins so eagerly that the arms finish the rep; the hands should arrive at the shins because the trunk folded, not because you stretched for them.
- Heels and hands slap the floor between reps and the bounce carries the next one; hover both a few inches up and the abs never get a rest.
- Once the pace climbs, the extension gets shorter every rep, so by rep fifteen the long hollow position has shrunk to a small knee tuck.
- Legs kick out hard on the way back to long, and that kick pulls the pelvis into an arch you then spend the rest of the set fighting.
Frequently asked
- How many tuck-ups should you do when you are new to the exercise?
- Three sets of 8 to 12 reps, three days a week, ending each set on the rep where the low back lifts off the floor. If you cannot keep it flat for eight, hold a hollow position with the knees bent for 20 seconds instead and come back to the moving version in a few weeks. Once three sets of 20 feel easy, take three seconds on the extension or move up to V-ups.
- How do I make the tuck-up easier or harder?
- To make it easier, start with the arms by your sides or the hands on your thighs instead of overhead, keep a slight bend in the knees on the way out, and stop the extension before the legs are fully long. To make it harder, reach the arms all the way overhead, keep the legs dead straight so it becomes a V-up, pause two seconds folded at the top, or hold a light ball between your hands.
- What is the tuck-up good for, and when should I choose something else?
- It trains the top and bottom of the rectus abdominis to fire together and builds the compression that a V-sit later demands, which makes it a good step up from a static hollow hold. Choose something else if you want anti-rotation or anti-extension strength for lifting, where planks, rollouts, and Pallof presses transfer better. If a deep fold does not agree with your back, hollow rocks give you the tension without the flexion.
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