Modified hundred

Lie faceup, legs raised, knees bent 90 degrees.

Inhale as you pump arms up and down five times, then exhale and pump five more times.

Do 10 times, for 100 pumps.

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Roll-up

Lie faceup, legs together, toes pointed, arms extended to ceiling, palms forward.

Inhale; exhale as you slowly roll back to start.

Single-leg stretch

Lie faceup.

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Switch legs 20 times.

Double-leg stretch

Lie faceup, legs raised with knees bent 90 degrees, toes pointed.

Inhale, stretching arms and legs out, legs together, arms next to ears (as shown).

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Exhale, bending knees and bringing arms alongside knees, to return to start.

Lift toes and balance on tailbone, heels close to butt (as shown).

Inhale as you roll back slowly until shoulder blades touch mat.

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Extend left leg in line with right thigh, toe pointed.

Inhale, then exhale as you roll down, arms extended to ceiling again.

Switch legs; repeat.

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“Done correctly, these exercises activate abs more than crunches do.

Olson took to the mat herself to model the moves.

Do them three times per week on nonconsecutive days and ab-racadabra!

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A core to adore!

See the full video

Master class video: Activate your core

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