Lying Ball Squeeze
A good exercise for your core stability and Adductors (inner thigh) muscle's especially suited for beginners.
Lie on your back, with both arms extended out to your sides. Keep your palms facing downwards, to avoid excessive rolling in your upper body throughout the movement.
Place a soft ball between your knees, holding it in place by squeezing your thighs together whilst keeping your abs contracted.
Begin the movement with your feet on the floor, slowly lowering your knees down to one side then the other.
Progress this movement by lifting both feet off the floor, however always work within your own limits.
Intermediates and advanced can progress the exercise by placing the ball between their ankles and aim to take both feet to the side.
Avoid twisting to far around; use your core and oblique muscles to control the movement. Would recommend using ankles weights with a soft ball, rather than a medicine ball, to avoid injury if you drop the ball.
Beginners perform 8 - 12 turns each side, feet flat on the floor.
Intermediates perform 12 - 15 turns each side, legs at 90 degrees, feet off floor.
Advanced perform 12 - 15 turns each side with straight legs.
Concentrate on contracting your abs throughout the movement and also squeezing the ball tight.