V-up Double Crunch
- Target muscle
- Iliopsoas, Rectus Abdominis
- Synergist muscles
- Obliques, Quadriceps, Sartorius
- Equipment
- Body weight
- Body part
- Waist
- Type
- Strength
The V-up Double Crunch is a bodyweight core exercise that simultaneously targets the iliopsoas (hip flexors) and rectus abdominis by driving both ends of your body toward each other in one controlled movement. The obliques, quadriceps, and sartorius assist throughout the lift. It is an effective progression beyond standard crunches and leg raises, building core strength and hip-flexor endurance without any equipment.
How to do the V-up Double Crunch
- 1Lie flat on your back with your legs fully extended and your arms stretched overhead, palms facing up.
- 2Press your lower back gently toward the floor and brace your core before you begin.
- 3In one controlled movement, raise both straight legs and your upper body at the same time, driving your hands forward toward your feet.
- 4Continue lifting until your body forms a V shape, with your torso and legs meeting above your hips and your hands reaching toward your shins.
- 5Pause briefly at the top and squeeze the rectus abdominis fully before lowering.
- 6Lower your upper body and legs together in a slow, controlled descent back to the starting position.
- 7Let your back and legs return fully to the floor before initiating the next repetition.
Form tips
- Keep your legs straight throughout the movement — a bent knee shortens the lever and reduces the demand on the iliopsoas and quadriceps.
- Initiate the movement by contracting your core first rather than swinging with momentum; think of pulling your navel toward your spine before you lift.
- Control the descent as deliberately as the ascent — a slow lower builds more rectus abdominis tension than dropping back to the floor.
- Exhale forcefully as you crunch up and inhale during the lowering phase to maintain consistent core bracing.
- If your lower back arches excessively at the bottom, shorten the range by stopping just before your legs touch the floor rather than going fully flat.
Common mistakes
- Swinging the arms and using momentum to get up rather than contracting the abs first, which shifts the work away from the rectus abdominis and strains the lower back.
- Bending the knees during the lift, which reduces the lever length and takes tension off the hip flexors and quadriceps.
- Letting the lower back arch and leave the floor at the bottom of each rep, which compresses the lumbar spine and can cause discomfort over repeated sets.
- Only reaching partway up and not compressing fully at the top, which cuts the effective range of motion short and underworks the iliopsoas.
- Holding the breath throughout the set, which increases intra-abdominal pressure unnecessarily — breathe out on the way up and in on the way down.
Frequently asked questions
What muscles does the V-up Double Crunch work?
It primarily works the iliopsoas (hip flexors) and rectus abdominis, with the obliques, quadriceps, and sartorius acting as synergists to stabilize the movement.
Where should I feel the V-up Double Crunch?
You should feel a strong contraction through the entire front of your core — the rectus abdominis from ribs to pelvis — along with tension in your hip flexors as you draw your legs up. If you only feel it in your lower back, reset your form and slow down the movement.
Is the V-up Double Crunch suitable for beginners?
It is a moderately challenging movement. Beginners should first build a solid base with standard crunches and lying leg raises separately before combining them into the full V-up Double Crunch.
How many sets and reps should I do?
Two to four sets of 8–15 reps works well for most people. Keep reps controlled — if form breaks down before you reach your target, stop the set and rest rather than grinding out sloppy repetitions.
What is a good alternative to the V-up Double Crunch?
The standard V-up (reaching toward the feet with straight legs) is a close variation. The jackknife sit-up is also comparable. For a lower-difficulty option, perform a lying crunch and a lying leg raise as separate exercises until you build the strength to combine them.
