How long should you hold the hollow body flutter kick for when you are new to the exercise?

Start with 2 to 3 holds of 15 to 20 seconds, reaching the arms by your sides instead of overhead to make the position more manageable at first. Add a few seconds at a time, and only reach the arms overhead once you can hold the easier version with the low back staying flat the whole time.

How can I scale the hollow body flutter kick up or down?

To make it easier, reach the arms toward your thighs instead of overhead, or bend the knees slightly to shorten the legs. To make it harder, reach the arms fully overhead and straighten the legs as much as possible, which both lengthen the lever against the lower abs.

What is the hollow body flutter kick good for, and when should it be avoided?

It combines a rigid hollow hold with dynamic leg work, building the time-under-tension and hip-flexion endurance behind more advanced hollow-body skills. Skip it, or reach the arms by your sides, if you can't yet hold a basic hollow position with the low back flat, since the flutter adds even more demand on top of a brace that isn't solid yet.

Intermediate

Hollow Body Flutter Kick

This combines the rigid hollow shape with a dynamic lower-body challenge. You hold the dish position, low back pinned to the floor, then flutter the straight legs in small alternating kicks so the lower abs and hip flexors work overtime to keep the shape from breaking. It is a great way to add time under tension and hip-flexion endurance to your core work.

Equipment: Body Weight
Body part: Abs
Type: Functional, Strength
Browse by muscle: Lower Rectus Abdominals, Upper Rectus Abdominals
Browse by movement: Core Brace

How to do it

1
Lie on your back and lift into a hollow with the low back pressed flat.
2
Raise the arms overhead or reach them toward your thighs to scale difficulty.
3
Lift both straight legs a few inches off the floor.
4
Flutter the legs up and down in small, quick alternating kicks.
5
Keep the low back glued to the floor the entire time.
6
Breathe steadily and hold the flutter for the prescribed time.

Tips

The moment your low back lifts off the floor, raise the legs higher to regain the brace.
Keep the kicks small and controlled rather than big and sloppy.
Reach the arms by your sides instead of overhead to make it easier.

Variations

Common mistakes

The head and shoulders drop down flat onto the floor partway through the set instead of staying lifted, losing half of the hollow shape.
The ribs flare up and out as the arms reach overhead, arching the mid-back even while the lower back stays pinned.
The breath gets held for the whole hold instead of continuing steadily, adding neck and jaw tension that isn't part of the drill.
The legs drift apart from each other during the flutter instead of staying close together, losing some of the tension through the hips.
Holding the position well past the point where the low back has already lifted off the floor trades hollow-body training for lower-back strain.

Frequently asked

How long should you hold the hollow body flutter kick for when you are new to the exercise?: Start with 2 to 3 holds of 15 to 20 seconds, reaching the arms by your sides instead of overhead to make the position more manageable at first. Add a few seconds at a time, and only reach the arms overhead once you can hold the easier version with the low back staying flat the whole time.
How can I scale the hollow body flutter kick up or down?: To make it easier, reach the arms toward your thighs instead of overhead, or bend the knees slightly to shorten the legs. To make it harder, reach the arms fully overhead and straighten the legs as much as possible, which both lengthen the lever against the lower abs.
What is the hollow body flutter kick good for, and when should it be avoided?: It combines a rigid hollow hold with dynamic leg work, building the time-under-tension and hip-flexion endurance behind more advanced hollow-body skills. Skip it, or reach the arms by your sides, if you can't yet hold a basic hollow position with the low back flat, since the flutter adds even more demand on top of a brace that isn't solid yet.

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