When most people think of "ab exercises," they imagine doing thousands of dull sit-ups or crunches. While crunches are a worthwhile exercise to help get firmer abs, they can be repetitive and boring. Below is a workout that targets the whole core, while steering clear of crunches.

Standing Russian Twists (3 x 10 reps)

Stand with your feet slightly wider than shoulder width apart, you legs and back straight and your shoulders relaxed. Hold a dumbbell or medicine ball out in front of you with both hands at about chest level. Pivot on your right foot and rotate your torso as far as you can to the right. Return to your starting position, then repeat on the other side. Keep your abs engaged throughout the exercise.

Bent Over Rows (3 x 10 reps)

With feet shoulder width apart and a straight back, bend your knees slightly and grab a barbell or dumbbells with an overhand grip. Bend forward over the bar and pull the bar up to your waist then return it to the bottom. Keep your eyes about 45 degrees forward and try to keep the lifting motion smooth and fluid.

Reverse Plank with Leg Raise (10 reps on each side)

Get into an inverted push-up position (same style as a push-up, but with your back facing the ground). Make sure your arms are straight and your fingers are facing down your body. While maintaining a straight body between your shoulders and your feet, lift your right leg and hold it 30cm or so off the ground for 3-5 seconds. Alternate legs.

Half Seated Leg Raises (3 x 10 reps)

Sit on the floor resting back on your forearms. With your feet straight out in front of you, lift them to a 45 degree angle, and then back down. To add variation and target your obliques, you can alternate bringing your legs down on each side of your body. Slowing your tempo down will add difficulty.

Single Arm Lunge (10 reps on each side)

Raise a dumbbell in your right arm above your head, keeping your arm close to your ear. Step forward with your left foot until your thigh is parallel to the ground. Push back off your left foot back to your initial position, and then repeat.

Reverse Wood Chop (3 x 10 reps)

You can do this either with a Cable Column machine or with a dumbbell or medicine ball. Hold the weight next to your right hip, and then raise the weight across your body, up to above your left shoulder (keeping your arms straight). Return the weight to your right hip and repeat.

Rock'n'Roller (3 x 10 reps)

Get into the 'plank' position with your forearms facing forwards. Keep your hand and feet in a fixed position and rock from side to side and far as you can, twisting your body as you go. Try to maintain a slow controlled movement. Rocking back and forth counts as one rep.