Single Leg Roll Aways develop strength in the abdominals, hip flexors and obliques. The exercise places the hip flexor under stress in a lengthened position, making roll aways a helpful range of motion exercise.
To progress to the movement ensure you hold a single leg bridge position for 10-15 seconds after performing a series of swiss ball crunches. This will ensure you have adequate core strength. Also learn the correct technique with Standing Roll Aways, before progressing to the single leg version
If you experience lower back discomfort, check your lower back position and also make sure your abdominal strength is advanced enough for this movement
Technique Tips - Single Leg Swiss Ball Roll Aways
Ensure a straight line can be drawn from your knee, through your hips and to your shoulders
Drawn your naval to your spine and contract your abdominals
Ensure there is no arching of your lower back in the full extended (ball away from you) postition
Point to sole of your no supporting foot towards the sky