Your core is like your pet dog. It's always by your side but sometimes you call out her name and she ignores you. Turning your core on sounds simple enough, but unless you've done the training below, it's quite hard. What's even worse, if you can't activate your core, a flat stomach is unachievable.

Why? If you're a girl who wears high heels regularly (that's pretty much any female), unless you have a strong core, your hips are forced into an angle that rotates your pelvis and causes you to stand with a larger curve in your lower back. And what does this curve do? It forces you to stick your stomach out. Not cool.

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So what do you need to do to combat this?

1. Lie on your back and use your index and middle fingers to find the bony part of your hip. Move both fingers towards the middle and then cough. That is your core!

2. Place one hand under the curve of your lower back.

3. Turn on your core by activating the muscles under your fingers and pulling your belly button towards the floor. Slightly rotate your hips and press your back down onto your hand. Did you notice your stomach flatten?

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The trick is to hold this position and take eight slow, deep breaths before a rest. Once you feel confident increase the difficultly by lifting one leg and then eventually both off the ground. The goal is to hold two legs straight out about 5cm off the floor with no pain in your lower back. To achieve this it will take daily practice for about a month.

From now on, every core exercise you do must start with this activation and if you want an instantly flatter stomach, rotate your pelvis, flatten your back and activate your core when standing in heels. It's that simple.

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