How to Do the Flutter Kicks

How to do it

1. Lie flat on your back on a firm surface, legs fully extended, arms down by your sides with palms pressing lightly into the floor or tucked under your glutes for lumbar support if your lower back tends to arch aggressively.
2. Pull your belly button toward your spine and press your lower back into the floor before anything else moves, because this braced position is the foundation the whole exercise depends on.
3. Lift both legs off the floor together until your heels are roughly six inches above the surface, which is low enough to create real tension but high enough to keep the movement controlled.
4. Raise your left leg to about a 45-degree angle while keeping your right leg at the six-inch height, then reverse the position in a smooth, alternating scissoring motion so your right leg rises as your left descends.
5. Keep each kick compact and deliberate rather than swinging the legs wide; the range of motion is small by design, and the work comes from sustaining tension, not from amplitude.
6. Breathe steadily throughout, exhaling as you might during a braced plank, and resist the urge to hold your breath when the burn sets in because oxygen delivery is what lets you maintain quality reps.
7. Count reps by each time one specific leg reaches the top of its arc, or count in seconds of continuous movement depending on how you prefer to track the set.
8. To finish, bring both legs together, lower them slowly to the floor while keeping the core braced, and only fully relax once both heels touch down, avoiding the snap-down that can stress the lumbar spine.

Form cues

• Press that lower back INTO the floor. Any gap under your lumbar means the hip flexors are doing all the work.
• Chin slightly tucked, not craned up. Your neck should be relaxed.
• Feet stay low. If your heels climb past 45 degrees you have lost the tension.
• Small, tight kicks. This is not a swimming drill; it is a tension drill.
• Breathe through it. In through the nose, steady out through the mouth.

Common mistakes

• Letting the lower back arch off the floor is the most common error, and it shifts load entirely onto the hip flexors and lumbar extensors while the abs contribute almost nothing; fix it by tucking hands under the glutes or reducing leg height until you can maintain full contact.
• Kicking with too large a range of motion turns the exercise into a leg swing and bleeds tension out of the core, so keep the travel between the two legs intentional and close rather than trying to maximize the sweep.
• Holding the breath to brace through the burn raises intra-abdominal pressure unnaturally and accelerates fatigue, meaning sets end prematurely; practice steady exhalation the same way you would in a plank.
• Letting the legs climb too high takes the hip flexors out of their hardest working range and makes the movement significantly easier than it looks, which defeats the purpose of using a low, sustained position.
• Rushing the cadence to hit a rep target faster produces sloppy alternating kicks that bounce rather than control, so slow the tempo deliberately if the movement starts to look like a splash rather than a steady alternating press.

Why do the Flutter Kicks?

• The sustained isometric demand on the abs builds genuine endurance in the rectus abdominis and transverse abdominis, which carries over to compound lifts like squats and deadlifts where a fatigued core is often the limiting factor long before the prime movers are taxed.
• Because the hip flexors must work hard to keep the legs elevated against gravity for extended sets, flutter kicks develop hip flexor strength and muscular endurance that directly benefits running stride mechanics and the top position of a knee raise.
• No equipment is required, making this one of the few exercises that can meaningfully challenge the abs and hip flexors together in a hotel room, a park, or any space large enough to lie down.
• The alternating unilateral leg action exposes left-to-right differences in hip flexor control early, giving athletes and general fitness trainees a useful diagnostic without any added loading.

Flutter Kicks variations

Elevated Flutter Kicks (legs at 45 degrees throughout)

A useful regression for beginners or anyone whose lower back arches at the six-inch position, since the higher starting height reduces the lever arm and makes lumbar control easier to maintain while the pattern is being learned.

Weighted Flutter Kicks (light ankle weights)

Adding even one to two pounds of ankle weight at the same low height substantially increases the hip flexor and ab demand, making this a practical progression once bodyweight reps stay clean for 30-plus seconds without form breakdown.

Flutter Kicks with Arms Overhead

Extending the arms overhead rather than keeping them at the sides lengthens the lever of the upper body and increases the challenge to core anti-extension, making it harder to prevent the back from arching off the floor.

Slow-Tempo Flutter Kicks (3-second count per rep)

Deliberately slowing each alternating kick to a three-second cycle removes momentum entirely and forces the abs and hip flexors to stay under tension without any ballistic assistance, which is effective for lifters who have mastered normal tempo but want more work without adding load.

How to program it

Flutter kicks are most commonly used as an accessory or finisher movement rather than a primary lift, typically appearing at the end of a session after heavier compound work. Most trainees structure them in timed sets ranging from 20 to 60 seconds or in rep-count sets of 20 to 50 alternating kicks, often for two to four rounds with short rest periods. They fit naturally into ab circuits alongside movements like planks and leg raises, where the goal is cumulative time under tension across the whole core. Higher-rep or longer-duration protocols are common among endurance athletes and those training for sports that demand sustained hip flexor output.

Flutter Kicks alternatives

Hanging Leg Raise

Bodyweight · Isolation

Dead Bug

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Decline Sit-Up

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Lying Leg Raise

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V-Up

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Knee Tuck

Bodyweight · Isolation