MariposasHow to Do the Inchworm
By Zachary, builder of Mariposas · Reviewed against published exercise-science sources (references)
· Last updated June 2026
The inchworm earns its place in warm-ups and full-body circuits because it simultaneously lengthens the posterior chain, loads the shoulder girdle, and forces the core to stabilize through a long range of motion, all without a single piece of equipment. Unlike a static hamstring stretch or a simple plank, it strings those demands together into one flowing movement, so you get mobility work and muscular activation happening at the same time rather than in separate isolated blocks. The walk-out phase exposes shoulder weakness that seated pressing never reveals, and the walk-back phase reveals exactly how stiff the hamstrings really are once fatigue starts to set in. It sounds simple, but done deliberately, it exposes a lot. You can log every inchworm session free in the Mariposas app and track your mobility progress over time.
How to do it
- Stand tall with feet hip-width apart and arms at your sides, taking a moment to root your feet flat and stack your hips directly over your ankles.
- Hinge at the hips and bend your knees just enough to plant both palms flat on the floor directly in front of your toes, keeping your fingers spread wide for a stable base.
- Begin walking your hands forward one at a time, keeping your core braced and your hips from sagging or piking dramatically as the hands travel out.
- Continue walking the hands out until your body reaches a full high-plank position, with wrists stacked under shoulders, a straight line from heels to crown, and glutes squeezed lightly to prevent lower-back hyperextension.
- Hold the plank position for one full breath, actively pressing the floor away with your palms to feel the shoulder engagement rather than just passing through the position.
- Walk your hands back toward your feet using the same controlled step-by-step motion, resisting the urge to lurch or hop, and let the hamstrings do the work of pulling your hips back up.
- Once your hands are back near your feet, push your hips high and hold for a beat in a pike-like position, feeling the hamstring stretch deepen before you stand back up.
- Return to standing by driving your hips forward and stacking your spine vertebra by vertebra, then reset your posture before beginning the next rep.
Form cues
- Hands flat, fingers spread, no collapsed wrists.
- Ribs down in the plank, not flared up to the ceiling.
- Walk the feet in slowly, let the hamstrings stretch rather than fighting them.
- One breath at the top of the plank, then walk back with control.
- Hips level during the walk-out, not seesawing side to side.
Common mistakes
- Rushing through the walk-out: treating it like a speed drill eliminates the shoulder stability demand and turns the movement into a sloppy burpee variation, so slow each hand placement down and own every inch of the floor.
- Letting the lower back hyperextend in the plank: this compresses the lumbar spine and shifts load away from the core, fixed by squeezing the glutes and pulling the ribs slightly toward the pelvis before pausing at the top.
- Bending the knees excessively on the walk-back: people do this to avoid the hamstring stretch, which is precisely what the inchworm is there to address, so try to maintain a soft but fairly straight knee as the hips travel upward.
- Pike-walking instead of plank-walking: when the hips stay high the entire time, the core never has to stabilize a neutral spine, which defeats a primary purpose of the drill, so focus on achieving a true flat plank before the return walk begins.
- Holding the breath: the inchworm transitions through positions that naturally want to trigger a breath-hold, but exhaling on the walk-out and inhaling on the return keeps the core working through intra-abdominal pressure cycling rather than just locking up rigidly.
Why do the Inchworm?
- The inchworm bridges mobility and strength work in a single movement, so it builds usable hamstring length rather than passive flexibility that disappears once you start loading the pattern.
- Because the shoulder girdle has to hold a loaded plank while the rest of the body is in motion, the core and shoulders develop dynamic stability together, which carries over directly to push-ups, overhead pressing, and any sport involving ground contact.
- As a warm-up tool, it raises core temperature, activates the posterior chain, and checks in on how well the shoulder and hip joints are communicating on a given day, giving a clear daily readiness signal before heavier work begins.
- The movement requires zero equipment and a small floor footprint, making it one of the highest-value bodyweight options available when training space or gear is limited.
- Repeated sessions tend to reveal asymmetries in hip shift or uneven hamstring restriction during the walk-back phase, which makes it a useful diagnostic as well as a training tool.
Inchworm variations
- Inchworm with Push-Up
- Adding a push-up at the bottom of the plank increases the upper-body strength demand significantly, making this a sensible choice once the basic form is clean and the shoulder stability is established.
- Inchworm to Alternating Knee-to-Chest
- Bringing one knee toward the chest at the top of the plank adds hip flexor and thoracic rotation demands, useful when warm-up time is short and multiple movement patterns need to be covered at once.
- Bent-Knee Inchworm (Regression)
- Keeping a generous knee bend throughout reduces hamstring tension and allows people with very tight posterior chains to still benefit from the shoulder and core demands without forcing a painful stretch.
- Inchworm with Lateral Walk-Out
- After reaching the plank, walking the hands out to one side before returning introduces rotational core stability, a useful progression for athletes whose sports involve lateral force production.
How to program it
The inchworm appears most often in the warm-up block, with many coaches and programs using 4 to 8 slow, deliberate reps as a primer before lower-body or upper-body strength work. Some full-body circuits use it as an active rest between heavier compound sets, typically keeping rep counts in the 5 to 10 range and emphasizing tempo rather than load. Because it is a compound bodyweight movement with no external resistance, progression comes from slowing the pace, adding variations, or increasing the number of reps per set rather than adding weight. It rarely shows up as a primary training stimulus for advanced lifters, but it remains a staple in movement prep for all experience levels because of how efficiently it addresses multiple physical qualities at once.
Inchworm alternatives
FAQ
- Is the inchworm a good warm-up before squats or deadlifts?
- Yes, and for specific reasons. The walk-back phase lengthens the hamstrings under mild load, which wakes up the posterior chain before it gets asked to produce force in a deadlift or absorb it at the bottom of a squat. The plank position also activates the core and shoulders, so by the time you get under a barbell, those stabilizers have already been reminded they have a job to do.
- How slow should an inchworm be?
- Slow enough that you can feel each phase distinctly. If a single rep takes less than about five seconds, it is probably being rushed. The walk-out should be deliberate enough that you notice if your hips start to sag. The walk-back should be slow enough that you feel the hamstrings working rather than just plopping your feet back to the floor.
- Can the inchworm help with hamstring flexibility long-term?
- Consistent use does tend to improve functional hamstring length over time, meaning the kind of flexibility that translates to movement rather than just passive range when lying down. Because the hamstrings are being stretched while the rest of the chain is under some tension, the nervous system adapts to the position in a more transferable way than purely passive stretching usually achieves.
- My lower back hurts during the plank portion. What is going wrong?
- Usually the hips are too high or the ribs are flared, both of which dump load into the lumbar spine rather than distributing it across the core. Try actively exhaling as you reach the plank position, pulling the lower ribs down slightly, and squeezing the glutes before pausing. If lower back pain persists during any exercise, consulting a qualified professional is worth doing before continuing.
- How is the inchworm different from a walkout or a bear crawl?
- A walkout is essentially the first half of an inchworm, walking hands out to a plank and returning, without the emphasis on the standing hip hinge at the start. A bear crawl moves the entire body across the floor in a quadruped position, emphasizing coordination and hip stability rather than hamstring flexibility. The inchworm is distinctive because it starts from standing and cycles through a full hip hinge, which is what makes it so useful as a posterior chain primer.