One of the favourite moves prescribed by Kayla Itsines and group fitness instructors everywhere, the straight-legged jackknife or V-up, as it’s also referred to, is a great way to tighten tummy muscles, but this move is not for everyone. “The V-up is a very difficult move to do for beginners,” says Level 1 CrossFit trainer Casper van Heerden. “The hollow hold is the first position to master because it’s the optimal beginning and end position you want to achieve when doing the V-up correctly.”
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Most of the time, if your core isn’t strong enough, you end up relying on other parts of your body, like your back, to support you during the jackknife, says Van Heerden. If you’re rocking a sturdy midsection, go for the V-up: you’ll work your core, butt, thighs and back, says boxing trainer Sanchia du Preez. “I add them into my routine every second day, combined with crunches and different variations of the plank,” she says.
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Simone Jacobs, trainer and owner of Ampt fitness centre in Joburg, says you should aim to keep your reps low. “You can tire these muscles quickly and you don’t want to end up doing your last sets incorrectly due to fatigue,” she says. Start with five and work up to sets of 10. Note: Avoid if you’re pregnant or have a weak back or core.
Toughen your torso with these simple – but super – progressions…
Half Hollow Hold
Lying on your back, extend your arms straight past your head and bend your knees. Now raise your feet about five centimetres off the ground, along with your shoulders, while keeping your lower back glued to the ground.
Hollow Hold
Same as the half hold, but your legs should be straight and raised just a few centimetres from the ground.
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Bent-Knee Jackknife
Start on your back, legs slightly bent, arms extended past your head, lower back glued to the floor. Without arching your back, contract your abs to raise your torso and legs simultaneously, bending your knees and swinging your arms to meet them in the middle.
Signs You’re Doing It Wrong…
Your back hurts. You’re likely arching your lower back (making a gap between your spine and the floor), causing strain in that region. Suck your belly button into your spine and engage your pelvic floor muscles to ground your back on the floor.
READ MORE ON: Fitness Fitness Advice