MariposasHow to Do the V-Up
By Zachary, builder of Mariposas · Reviewed against published exercise-science sources (references)
· Last updated June 2026
The V-Up earns its place in core training because it demands simultaneous movement from both ends of the body, forcing the abs and hip flexors to coordinate under tension rather than just brace statically. Unlike a crunch, which anchors the lower body and only flexes the spine, or a leg raise, which keeps the upper body passive, the V-Up fires both ends at once, creating a full compression of the anterior chain at the top of every rep. That coordination challenge means more total muscle involvement per rep, and the brief balance point at the top adds a proprioceptive element most floor core work completely skips. If you want to track your progress on V-Ups alongside the rest of your training, you can log them for free in the Mariposas app.
How to do it
- Lie flat on your back on a firm surface with your legs fully extended and your arms stretched overhead, biceps close to your ears, body in one long line from fingertips to toes.
- Press your lower back gently into the floor before you move, so your core is already engaged rather than relying on momentum from a loose starting position.
- Exhale sharply and simultaneously lift your straight legs and your straight arms toward each other, keeping your knees locked and your elbows extended throughout the ascent.
- Aim to reach your hands toward your feet (or shins if flexibility is limited) so your body forms a V shape, with only your tailbone and glutes lightly touching or hovering above the floor.
- At the top, pause briefly to confirm balance and control rather than bouncing through, which is where the abs and hip flexors are under the most tension together.
- Inhale and lower both ends back toward the floor in a controlled descent, resisting gravity rather than dropping, so the eccentric phase counts as real work.
- Touch the floor lightly at the bottom (or hover just above it for a harder version) before initiating the next rep, avoiding any rocking or swinging of the arms to generate momentum.
- Complete your target reps with the same range of motion on every rep, because a full rep with a shorter range beats a sloppy rep chasing height that the body isn't ready for.
Form cues
- Reach fingertips to toes, not just up to the ceiling.
- Squeeze your quads, knees stay locked the whole way.
- Exhale hard on the way up, breathe in on the way down.
- Control the descent, don't just fall back to the floor.
- Keep arms glued alongside your ears at the start.
Common mistakes
- Bending the knees on the way up: this shortens the lever dramatically and takes load off the hip flexors and lower abs, making the exercise far easier than intended; focus on locking out the quads before the rep even starts.
- Using arm swing for momentum: swinging the arms like a counterweight lets the hip flexors coast through the hard part of the lift, so slow the arm path down and think of the arms as passengers, not drivers.
- Only raising the legs while the upper body barely moves: this turns the V-Up into a leg raise with arm decoration, losing the bilateral coordination that makes the exercise useful; both ends should reach the same height simultaneously.
- Holding the breath: bracing is necessary, but a full breath hold leads to fatigue, lightheadedness, and loss of tension quality; time the exhale to the crunch at the top so intra-abdominal pressure stays managed.
- Hyperextending through the lower back at the bottom: landing with an arched lumbar spine dumps load off the abs between reps and can accumulate stress on the lumbar discs; hover the legs an inch off the floor instead of fully relaxing if the arch becomes unavoidable.
Why do the V-Up?
- The simultaneous lift from both ends trains the abs to generate force while the hip flexors are also working hard, a combination that transfers directly to athletic movements like kicking, sprinting, and gymnastics skills where the trunk has to stay rigid under dynamic hip flexion.
- Because the spine flexes against gravity while the hips also flex, the abs get a longer functional range of motion than in most crunching variations, which tends to develop more usable strength through the full arc rather than just at a partial range.
- The balance point at the top requires isometric stabilization of the core and hip flexors simultaneously, building the kind of midline stability that carries over to loaded lifts like squats and overhead pressing where a neutral, stable trunk is critical.
- V-Ups require zero equipment and minimal space, so they fit easily into warm-ups, finishers, or travel workouts without any setup time, making consistency easier to maintain across different environments.
- The movement has a clear, quantifiable range of motion and a visible top position, which makes progression straightforward: when reps get easy, adding a slow eccentric, a pause at the top, or moving to a weighted variation gives an obvious next step.
V-Up variations
- Tuck-Up
- Both knees bend as they rise to meet the chest, shortening the lever considerably, which makes this the go-to starting point for anyone who cannot complete a full V-Up with straight legs and controlled descent.
- Single-Leg V-Up
- One leg stays low while the other rises to meet the hands, reducing the load by roughly half and allowing trainees to build coordination on each side before combining both legs.
- Weighted V-Up
- A light dumbbell or weight plate held between the hands adds load at the end of the longest possible lever, making this appropriate once bodyweight reps are controlled and consistent across multiple sets.
- V-Up to Hollow Hold
- After completing a rep, the lifter holds the hollow body position at the bottom for two to three seconds before the next rep, turning a strength exercise into a combined strength and isometric endurance drill suited for gymnastic-style programming.
How to program it
V-Ups tend to appear most often in the 10 to 25 rep range, used either as a core finisher after main strength work or as part of a circuit during conditioning blocks. In strength-focused programs they usually sit at the end of a session so fatigue from them doesn't interfere with heavier compound lifts. Some gymnastic and calisthenics programs cycle them earlier as skill prep, especially when the session includes L-sit or toes-to-bar progressions that share similar demands. Sets are commonly kept moderate (two to four) with attention on quality, since rep quality degrades faster than it appears when momentum starts creeping in.
V-Up alternatives
FAQ
- Why do my hip flexors cramp during V-Ups?
- Hip flexor cramping usually means the muscle is working hard in a shortened position at the top of the movement while also being fatigued, a combination that causes involuntary cramping. It tends to happen more when someone rushes reps or holds their breath. Slowing the tempo, exhaling at the top, and building volume gradually over weeks typically reduces cramping as the hip flexors adapt to the demand.
- Are V-Ups bad for your lower back?
- For most people with healthy spines, V-Ups are not inherently harmful, but they do load the lumbar region through the hip flexors pulling on the pelvis. The risk rises when someone hyperextends the lower back at the bottom between reps or uses so much momentum that they lose control. Maintaining a posterior pelvic tilt at the bottom (or hovering legs rather than dropping them) keeps the lumbar spine safer throughout.
- What's the difference between a V-Up and a jackknife sit-up?
- The terms are sometimes used interchangeably, but a jackknife sit-up often refers to a movement where only the torso rises to meet the knees, while the legs may bend. A true V-Up keeps both legs and both arms straight, which creates a longer lever on both ends and demands more from both the abs and hip flexors.
- How many V-Ups should I do to feel a difference?
- This depends on baseline conditioning, but many people notice significant core fatigue and muscular awareness within the first one to three sessions simply because the bilateral coordination is unfamiliar. Consistent practice a few times per week over four to six weeks tends to produce visible improvements in control, range of motion, and rep capacity, which is generally when people report the exercise feeling meaningfully harder and more productive than crunches.
- Can I do V-Ups every day?
- Abs and hip flexors are relatively fatigue-resistant compared to larger muscle groups, so some people do train them daily. The practical limitation is that if reps get sloppy because of residual fatigue, form breaks down and the exercise loses most of its value. Many programs use them three to five times per week and find that's sufficient to drive adaptation without accumulated technique degradation.