The knee tuck is a bodyweight abdominal exercise performed in a high plank, hopping both feet in so the knees land under the hips, which trains theabsand hip flexors. It is the implement-free version of the pattern: with nothing under the feet, they leave the floor for a moment, which makes it the same movement as theplank jump in, while discs or straps keep the feet loaded throughout. Expect a short, sharp tuck rather than a slow one. Coaches use it in bodyweight circuits.
What Muscles Does the Knee Tuck Work?
- Primary: Rectus abdominis (lower abs), iliopsoas (hip flexors)
- Secondary: Rectus femoris, external obliques
- Tertiary: Anterior deltoid, triceps, calves
How Do You Set Up for the Knee Tuck?
Stand facing a clear stretch of floor, then plant your hands and walk your feet back into a high plank. Set the wrists under the shoulders, fingers spread and elbows straight, with the feet together and the body in one line from head to heels. Press the floor away, tuck the pelvis under and drop your gaze between your hands. Rise onto the balls of the feet.
How Do You Perform the Knee Tuck?
- Lock the plank with straight arms, hips level and both feet together on the toes.
- Push the floor away with the hands and take the weight forward over the wrists.
- Hop both feet in together, curling the pelvis so the knees land under the hips.
- Land softly on the balls of both feet with the back rounded and the shoulders stacked, then hold one count.
- Hop the feet back out to the plank, letting the abs pay out the length rather than dropping the hips.
- Land in a straight plank with the hips level and the feet together, ready for the next tuck.
What Are the Key Form Cues?
- Lead with the belly, not the feet: pull the hip bones toward the ribs so the hop follows the pelvic curl.
- Push the floor away hard: pressure through the palms unloads the feet, which is what lets them travel.
- Land quietly on the balls of the feet at both ends of the rep.
- Keep the shoulders over the hands as the knees arrive, not behind them.
- Hold the head in line with the spine instead of lifting it as the knees come in.
What Are the Most Common Mistakes?
- Hopping fast for reps: the legs bounce and the abs never curl, so pause a count with the knees in.
- Letting the hips drop as the feet land back: the lower back arches under the body weight, so stop the legs when the plank is straight.
- Piking the hips upward on the tuck: the hip flexors pull the legs in while the trunk stays long, so keep the hips only as high as the pelvic curl lifts them.
- Landing flat and heavy: the shins and knees take the impact, so keep every landing on the toes.
- Letting the hands creep behind the shoulders: the wrists load and the plank shortens, so reset your hand position between sets.
What Are the Best Knee Tuck Variations?
- Single-leg knee tuck: hop one knee in at a time, an anti-rotation demand and a regression on impact.
- Sliding knee tuck: discs under the feet remove the hop and keep tension all the way through.
- Feet elevated knee tuck: the toes start on a low box, which shifts more weight onto the hands.
- Knee tuck with a push-up: pressing between tucks adds chest and triceps work.
- Tuck jump to plank: standing between reps, turning the drill into conditioning.
How Do You Progress the Knee Tuck?
- Raise the feet onto a low step; leverage is the only load a bodyweight tuck offers.
- Build from 8 reps up to 15 per set, pausing with the knees in on every one.
- Add a set per week from 2 up to 4 while the plank stays straight to the last rep.
- Hold the tuck three counts, or move to discs for a slow return, once 15 reps are routine.
How Should You Program the Knee Tuck?
Use the knee tuck late in a session as a core finisher, or as a station in a bodyweight circuit where the wrists are already warm. Train it two to three times a week for 2 to 3 sets of 8 to 15 reps with 30 to 45 seconds of rest. Pair it with a hollow hold so the abs also work without the hop taking over.