Abdominal fat: more effective than crunches, the v-up is ideal for losing belly fat

While crunches still dominate many ab sessions, more coaches are nudging people towards a tougher movement that lights up the whole core and can support faster progress with stubborn belly fat: the v-up.

Why belly fat is so hard to lose

Belly fat isn’t only about appearance. How much fat the body holds around the abdomen is shaped by hormones, genetics, age, stress levels and poor sleep, and this area often proves slower to change than others.

There are two main types to understand:

• Visceral fat: the fat stored deeper in the abdomen, surrounding internal organs. It is strongly associated with health concerns such as type 2 diabetes and cardiovascular disease.
• Subcutaneous fat: the softer layer just beneath the skin. It carries less health risk, but it can be equally frustrating to shift.

Training one body part won’t magically “melt” belly fat, but the right exercises can strengthen the core, raise energy expenditure and support long-term fat loss.

That’s why many trainers push a whole-picture plan: a balanced diet, adequate sleep, stress management and consistent activity that blends cardio with strength training. Within that approach, one bodyweight exercise tends to stand out for core development: the v-up.

An extra piece many people overlook is daily movement outside workouts (often called non-exercise activity): walking more, taking the stairs and breaking up long periods of sitting can make a meaningful difference to overall calorie burn, which is what ultimately drives fat loss.

What is a v-up and why coaches rate it higher than crunches

A v-up (often called a jackknife) is a bodyweight exercise where you lift your upper body and legs together so your body forms a “V” at the top. Unlike classic crunches, which mainly emphasise the upper part of the abs, the v-up demands more from the entire abdominal wall.

A well-executed v-up recruits multiple muscle groups at once:

• Rectus abdominis (the “six-pack” muscles)
• Obliques along the sides of the waist
• Deep core muscles, including the transverse abdominis
• Hip flexors, which assist in lifting the legs

The v-up trains the whole core in a single movement, blending strength, coordination and mobility with no equipment required.

Coaches (including US trainer Tatiana Lampa) often favour v-ups over crunches because they typically involve more muscle fibres per repetition and require tighter control. Over time, that higher demand can contribute to better muscle definition and a greater calorie cost compared with easier ab work.

How to perform a proper v-up (jackknife)

All you need is a mat or a comfortable, non-slip floor.

1. Lie on your back with legs straight and together, arms extended overhead.
2. Brace your core as though preparing for a gentle poke in the stomach.
3. Lift your legs and upper body at the same time, keeping both as straight as you can.
4. Reach your hands towards your toes, creating a “V” shape at the top.
5. Hold briefly, balancing on your tailbone.
6. Lower down slowly and with control, avoiding a full “collapse” onto the floor between repetitions.

Lampa suggests beginning with 2 sets of 12 repetitions. As the movement becomes more manageable, build up gradually:

• Intermediate: 3 sets of 15 repetitions
• Time-based option: 3 sets of 45 seconds, completing as many controlled reps as possible

Controlled repetitions beat rushed, jerky ones. With core training, quality delivers better results than sheer volume.

A helpful addition before your first set: spend 3–5 minutes warming up your hips and spine (for example, dead bugs, glute bridges or gentle cat-cow movements). It can improve control in the v-up and reduce the temptation to “swing” through the lower back.

Common mistakes that ruin the exercise

Because the v-up is challenging, technique often slips as soon as fatigue builds. Trainers regularly spot these issues:

• Yanking the neck or over-rounding through the shoulders
• Flinging the legs up with momentum rather than lifting with control
• Letting the lower back arch sharply off the floor
• Dropping legs and shoulders heavily between repetitions

To keep your spine happier and get more from each rep, lightly draw the belly button in towards the spine, exhale as you lift, and avoid snapping through the lower back to “force” the top position.

Beginner-friendly v-up variations and progressions

The full v-up isn’t the only route. Beginners, people returning after time off, or those with lower-back sensitivity can still train the abs hard with a safer stepping-stone.

Variation	How it works	For whom
Tuck v-up	Bring knees towards the chest rather than keeping legs straight.	Beginners or anyone with limited hamstring flexibility.
Single-leg v-up	Lift one leg at a time, alternating sides each rep.	Those building strength or managing hip discomfort.
Supported v-up	Hold a stable object behind your head to reduce strain.	People with a weaker core or recovering from injury (with medical approval).
Weighted v-up	Hold a light dumbbell or weight plate for added resistance.	Advanced users who want a bigger challenge.

Starting easier and progressing steadily lowers injury risk and improves consistency-far more valuable than going all-out once a week and then needing days to recover.

Three other bodyweight moves that help flatten the stomach

Even though the v-up is a standout, good coaches rarely rely on just one exercise. A simple home plan can pair v-ups with three other bodyweight moves that cover different elements of core strength and overall fat-loss support.

1. Plank variations for deep-core strength

The standard plank strongly targets the transverse abdominis, a deep muscle that wraps around the waist like a natural corset. It helps stabilise the spine and can make the midsection look firmer as body fat drops.

For a forearm plank: lie face down, then prop yourself up on your forearms and toes. Keep a straight line from head to heels, shoulders stacked above elbows, with glutes and abs engaged.

To progress:

• Dynamic plank: move from forearms to hands and back down, keeping hips steady.
• Side plank: rotate onto one forearm with feet stacked to emphasise the obliques.

Planks create the stability base that supports everything from v-ups to running and weight training.

2. Mountain climbers for cardio and core

Mountain climbers combine core engagement with a cardio hit that raises heart rate and calorie burn. From a high plank, drive one knee towards the chest, then switch legs in a quick, running-style rhythm.

Because your abs, shoulders and legs work together, mountain climbers are effective in intervals-such as 30 seconds on, 30 seconds off-which supports overall fat loss, including around the abdomen.

3. Reverse crunches to hit the lower abs

Reverse crunches place a little more emphasis on the lower portion of the rectus abdominis. Lie on your back with knees bent at 90 degrees and feet lifted. Using your abs, curl your hips gently towards your rib cage so the tailbone lifts slightly, then lower under control.

Combined with v-ups, reverse crunches round out the front-of-body challenge without needing heavy equipment.

How to build an effective v-up core routine

A straightforward circuit completed three times per week can support belly-fat reduction when matched with a healthy diet and enough daily movement.

• V-ups: 2–3 sets of 12–15 reps
  
• Forearm plank: 3 sets of 30–45 seconds
  
• Mountain climbers: 3 sets of 30–40 seconds
  
• Reverse crunches: 2–3 sets of 12–15 reps
  

Rest 30–45 seconds between sets. Aim for steady, repeatable effort-not burning out after the first round.

If you already train regularly, this circuit often works best at the end of a workout, once the core is warm and properly “switched on”.

What “burning belly fat” really means

The idea of spot reduction-losing fat from one specific area by exercising that area-doesn’t hold up scientifically. Where fat comes off first (or last) is largely determined by genetics and hormones.

V-ups still matter because they:

• build muscle in the midsection,
• increase total energy use,
• and improve posture, which can change how the waistline looks.

As overall body fat decreases through nutrition, cardio and strength work, stronger abdominal muscles become more visible.

Two terms that often get used loosely are worth defining:

• Core: not only the abs at the front, but also the lower back, obliques, diaphragm and pelvic floor.
• Metabolism: the energy the body uses for basic functions and activity; building muscle can raise it slightly over time.

Risks, benefits and who should be cautious with v-ups

The v-up is demanding and isn’t ideal for everyone in its classic form. If you have a history of lower-back pain, herniated discs, hip issues or you’ve had recent abdominal surgery, seek advice from a GP, physiotherapist or suitably qualified professional before attempting it.

For healthy individuals, the upsides are compelling:

• a stronger, more stable trunk
• improved posture when sitting and standing
• better performance in sport and day-to-day tasks
• solid support for long-term fat-loss efforts

A common scenario is the desk worker who feels a nagging lower-back ache and notices weight settling around the middle. Introducing a short routine of v-ups (or a regression), planks and mountain climbers three times weekly-alongside regular walks and fewer ultra-processed snacks-can gradually improve both comfort and shape.

Used sensibly, the v-up becomes less of a social-media stunt and more of a practical tool: a tough, efficient exercise that helps tighten the core and steadily chip away at stubborn abdominal fat over time.