Sit ups are boring and they don’t work very well. You’re more likely to work your hip flexors and hurt your lower back than you are to get a good core workout in.

Crunches are better, but they are limited – they teach you fantastic control, and work your lower abs particularly well, but their scope is slightly limited, they, too, can be pretty boring, and they plateau very quickly. It’s not uncommon for people to be able to perform 50 or more crunches without fatiguing, which is simply a waste of time. Would you ever perform 50 reps on the bench, of 50 curls? No, you would recognise that the stimulus is too low, and you would be right.

The same applies to the core, to crunches and sit ups. They won’t be likely to help you build too much muscle.

They also don’t burn very many calories. As building a six pack is as much about uncovering muscles as building mass, this is pretty crucial. You need a decent caloric deficit to lose the unwanted fat around your belly. This means keeping a strict, lower calorie diet, and engaging in heart-raising, higher energy exercise. Crunches and sit ups don’t cut the mustard, here.

Neither are the most effective exercises for your core. From bird dogs to ab rollouts, planks to hollow holds, Turkish get ups to kettlebell swings, there are dozens of exercises that are much better. We’re going to look at one of them today.

Crunch Kicks

Crunch kicks represent a higher energy ab exercise. They can be used well on their own, very well as part of a larger circuit, or as an incredibly effective warm up for the legs, core, and glutes – they will boost your heart rate, get blood into the muscles, improve your flexibility and mobility, burn more calories than crunches and sit ups, and help to build up core strength and control.

They specifically target your hip flexors, upper quads, and lower abs, though the whole core will need to engage, with full-functioning stability and proprioception being used and required throughout.

To perform crunch kicks:

  • Stand with your feet shoulder width apart
  • Keep a neutral spine, trying not to round your lower back
  • Draw your core in and activate your glute
  • Lift one leg as high as possible and touch it with the opposite hand
  • Return to the start, controlling your leg’s descent, and repeat on the other side
  • To further emphasise core strength and control, move slowly. To use it as more of a warmup and mobility drill, move faster, kicking upwards at speed and controlling the descent. To use it as a heartrate booster, for example as part of a circuit, go for speed, whilst maintaining control and proper technique throughout.

Top tips

To perform crunch kicks correctly, you need to maintain a straight back and neutral spine. To do this, bring your abs in towards your ribs. Open your chest, broadening your collarbones to the ceiling and keeping your gaze straight ahead. Keeping your gaze fixed on one point in this way will also help you to maintain good balance throughout the movement.

Keep your core engaged and your breath steady throughout. This isn’t a ballistic stretch – everything should be controlled, even if you are going for faster reps. Breathe out as you reach out to touch your foot and in as your leg lowers. Keep your lower abs engaged.

Try to move fluidly. If you can, bring one leg up as soon as the other foot touches the ground. This will be hard at first, so take your time if you need to. Focus on working up to this kind of speed, keeping movements smooth and controlled throughout.