Abdominal strengthener and Hip joint mobility exercises

 All Fours Footwork (above) - start with knees on the floor or with legs straight in a usual plank. Walk feet in until knees are under hips (keep knees off floor). Move between the two positions 5 times and gradually increase.

Hip joint mobility and active hamstring flexibility   (above and below)
Step 1. Start with your feet hip width apart, bend from hips and keep a straight back (keep extending your spins so you feel like your spine is being pulled away and your hips pulled back). This will be a great stretch.
Place your hands on something that allows you to keep a straight back.

Step 2. Tilt hips from side to side, you may feel stretching in the legs or a loosening in the hip joints.