Forget sit-ups — these 5 moves sculpt your abs in just 15 minutes

Woman doing mountain climbers outdoors during ab workout
(Image credit: Shutterstock images)

Kayla Itsines has shared an exclusive abs workout with Tom’s Guide — and it only takes 15 minutes and 5 ab exercises to complete.

As a fellow personal trainer, there’s nothing I enjoy more than taking a break from programming and trying out other people’s hard work. And with a huge social media following to back her (a casual 16 million on Instagram alone and counting), it seems just about everyone wants to train like Itsines — us included. 

In collaboration with Sweat, Itsines says, “This combo of ab exercises will really fire up your core. It’s a quick workout that will take you less than 15 minutes, and you can do it anywhere. You don’t even need a yoga mat.” Sounds good to us.  

While I might be attacking this abs workout from my tiny city apartment, you could do this anywhere — from the beach or a hotel room. “These movements will target your abs and core and are designed to improve core strength and stability,” says Itsines. 

“There are so many benefits to building your core strength! A stronger core can help you in other workouts and reduce the risk of injury while making it easier to perform other everyday movements, like picking up your kids.” Here it is.

Kayla Itsines’ 15-minute, 5-move abs workout 

Complete each exercise once through before taking a 30-second rest. Repeat for 4 laps of the circuit. Below, Itsines explains how to do each ab exercise safely. 

Toe taps: 30 seconds

Kayla doing toe taps touching toes with both legs extended

(Image credit: Kayla Itsines)

How to do toe taps:

  • Raise your legs off the floor so that they form a 90-degree angle at your hips, and place your hands behind your ears
  • Engage your abdominal muscles by drawing your belly button toward your spine
  • Extend your arms to bring your hands up towards your feet — slowly lifting your head, shoulder blades and torso off the mat
  • Return your torso, shoulder blades and head to the mat. Breathe deeply throughout.

Ab bikes: 30 seconds

How to do ab bikes:

  • Place your hands behind your ears and gently raise both your legs and your head and shoulders off the mat
  • Keeping your right leg extended, bend your left knee and draw it towards your chest. At the same time, rotate your torso to the left to bring your right elbow to your knee
  • Untwist your torso and extend your left knee to return to the starting position
  • Repeat the same movement on the other side
  • Continue alternating between left and right, inhaling for four repetitions and exhaling for four repetitions.

Side plank: 30 seconds per side

How to do a side plank:

  • Place your left forearm firmly on the floor, ensuring that your elbow is directly below your shoulder and your forearm is parallel to (in line with) the short edge of your mat
  • Extend both legs and, using your obliques, gently raise your hips off the mat
  • Position your feet one on top of each other or place your left foot on the mat in front of your right
  • Hold this position for half the specified time before switching sides.

Bent-leg jackknife: 30 seconds

Kayla performing a jackknife with knees bent and arms extended

(Image credit: Kayla Itsines)

How to do a bent-leg jackknife:

  • Lie on your back with your arms extended above your head
  • Engage your abdominal muscles by drawing your belly button toward your spine
  • Bend your knees and, using your abdominals, draw them towards your chest, keeping your feet stay together
  • At the same time, bring your arms forward toward your feet, slowly lifting your head, shoulder blades and torso off the mat
  • Slowly lower your arms and extend your legs back to the starting position without lowering your feet to the floor.

Mountain climbers: 30 seconds

How to do a mountain climber:

  • Place both hands on the yoga mat shoulder-width apart and both feet together behind you, resting on the balls of your feet
  • Gently draw your ribs to your hips to engage your core
  • Keeping your left foot on the floor, bend your right knee toward your chest
  • Extend your right leg to return to the starting position. Repeat the same movement on the other side and continue alternating
  • Inhale for four mountain climbers and exhale for four mountain climbers.

This interview was set up in collaboration with ICR, who represent iFIT, the company behind award-winning brands like the Sweat app, which is Kayla Itsines’ workout app for women.

More from Tom's Guide

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Sam Hopes
Senior Fitness Writer, Fitness and Mobility Coach

Sam Hopes is a level 3 qualified trainer, level 2 reiki practitioner and senior fitness writer at Tom's Guide. She is also currently undertaking her Yoga For Athletes training course. Sam has written for various fitness brands and websites over the years and has experience across brands at Future such as Live Science, Fit&Well, Coach, and T3.

Having worked with fitness studios like F45 and Virgin Active, Sam now primarily teaches outdoor bootcamps, bodyweight, calisthenics and kettlebells. She also coaches mobility and stretching-focused classes several times a week and believes that true strength comes from a holistic approach to training your body.

Sam has completed two mixed doubles Hyrox competitions in London and the Netherlands and finished her first doubles attempt in 1:11.

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