One of the core's most important jobs is to hold our bodies upright, despite the poor-posture abuse we give them. This simple yet challenging move can help you retrain and strengthen your abdominals and back so that you'll stand taller and look more fit.

Positioning

Kneel on an exercise mat or carpeted surface and place your hands on the mat, under your shoulders, about shoulder-width apart. Keep your spine in neutral alignment.

The Move

Slowly lift an opposite arm and leg up together. Pause, then return to the starting position. Repeat with the other arm and leg. Alternate in this fashion for the suggested number of repetitions.

Advanced Tip

Try to gradually increase the number of repetitions you perform in order to make this exercise more challenging.

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