For your rectus abdominus and oblique muscles: Use a 45-lb weight. Grasp it with each hand at opposite sides. Twist to the right and perform a situp.When you come up to starting position, move the weight to the front of your chest. Now twist to the left and go down for a situp. Perform four sets of ten repetitions. Use a weight that gives a good workout and is doable for you.
Disclaimer: None of the above information can be taken as a substitute for advice from a medical professional such as a physician.
My third book, Pocket Guide to Fitness, is available on www.louizapatsis.com, http://www.authorhouse.com, www.bn.com and http://www.amazon.com. If you look up my name on those Web sites, you will find my other books The Boy in a Wheelchair and Life, Work and Play: Poems and Short Stories.