Is easy and does not take very long, although I would recommend doing this on a hard surface with a block and some sandbags to support the weight. Simply place the block into the heels of your feet and slowly walk your heels away from the floor. This will be very easy to spot, but will increase your core strength, and help to strengthen your legs and hips.
* The Cobra. This is a very hard and long pose, you need a very strong body to hold this, you could almost consider this to be a full backbend, but more accurately a full Cobra. You start this in the standing position, with your back against a wall. Move your arms down the wall, and take a deep breath. As you inhale, turn your body to the right, and place your head against the wall. Keep your feet flat on the floor. Take a deep breath. As you exhale, swing your body to the left, and place your head between your arms, or between your arms and the wall. Bend your knees slightly. Stay in the pose for about 10 seconds. You will feel this as the contraction of your abdominal muscles. Return to the standing position, and slowly stand back up. Your muscles will be exhausted, your back more flat, your head more away from the wall. Swing your body back to the center, and rest in the Plank.
* The Side Plank. This is actually 2 easy steps, and one difficult step, the first step is to lay down flat on the floor with your stomach facing the wall, and your arms beside your body. Next, bring your legs over the armholes of your dress pants, and raise your head off the floor. If you are wearing shoes, place your feet flat on the floor. If you are not, raise your knees off the floor, and cross your legs, resting your back on your thighs. Stay in this position for about 10 seconds. Switch legs and plank.
* The Seated Spinal Twist. This is easy, just place a rolled up blanket or pillow under your head and lower back. Hold this for about 10 seconds. Switch legs and repeat. Inhale and switch sides, and again exhale and leave the pose.