When sitting, keep your back in a normal, slightly arched position. Make sure your chair supports your lower back. Keep your head and shoulders erect. Make sure your working surface is at the proper height so you don't have to lean forward. Once an hour, if possible, stand, and stretch. Place your hands on your lower back and gently arch backward.

• Plan ahead what you want to do and do not be in a hurry.
  
• Position yourself close to the object you want to lift.
  
• Separate your feet shoulder-width apart to give yourself
  a solid base of support.
  
• Bend at the knees.
  
• Tighten your stomach muscles.
  
• Lift with your leg muscles as you stand up.
  
• Don't try to lift by yourself an object that is too heavy
  or an awkward shape.
  
• Get help.

Picking Up a Light Object
To lift a very light object from the floor, such as a piece of paper, lean over the object, slightly bend one knee and extend the other leg behind you. Hold on to a nearby chair or table for support as you reach down to the object.
 
Picking Up a Heavy Object
Whether you are lifting a heavy laundry basket or a heavy box in your garage, remember to get close to the object, bend at the knees, and lift with your leg muscles. Do not bend at your waist.  When lifting luggage, stand along side of the luggage, bend at your knees, grasp the handle and straighten up.
 
Holding An Object
While you are holding the object, keep your knees slightly bent to maintain your balance. If you have to move the object to one side, avoid twisting your body. Point your toes in the direction you want to move and pivot in that direction. Keep the object close to you when moving.
           
Placing an Object on a Shelf
If you must place an object on a shelf, move as close as possible to the shelf. Spread your feet in a wide stance, positioning one foot in front of the other to give you a solid base of support. Do not lean forward and do not fully extend your arms while holding the object in your hands.
 
If the shelf is chest high, move close to the shelf and place your feet apart and one foot forward. Lift the object chest high, keep your elbows at your side and position your hands so you can push the object up and on to the shelf. Remember to tighten your stomach muscles before lifting.

Tips for Proper Use of Backpacks
Backpacks that are too heavy or are worn incorrectly can cause problems for children and teenagers. Improperly used backpacks may injure muscles and joints. This can lead to severe back, neck, and shoulder pain, as well as posture problems.

Choosing the Right Backpack
The correct use of both of the wide, well-padded shoulder straps will help distribute the weight of the backpack. When choosing a backpack, look for the following features:

• Two wide, padded shoulder straps
• Padded back
• Waist strap
• Lightweight regular or rolling backpack
  

To prevent injury when using a backpack, always use and tighten both shoulder straps, pack light, organize, remove items that do not need to be in the pack, lift properly, and build muscle strength. Parents also can help by encouraging their child or teenager to tell them about pain or discomfort that may be caused by a heavy backpack.

• Do not ignore any back pain in a child or teenager.
• Talk to the school about lightening the load.
• Be sure the school allows students to stop at their
  lockers throughout the day.
• Team up with other parents to encourage changes.
• Consider buying a second set of textbooks for your
  student to keep at home.
  

Caring for an infant puts stress on your back. Initially, you may be lifting the 7- to 10-pound baby up to 50 times a day. By the time the child is a year old, you are lifting and carrying 17 pounds. Two years later, you will be lifting a 25- to 30-pound child. Here are ten ways that new mothers can help reduce their risk of injury and back pain.

• Begin exercising soon after delivery to restore muscle tone to the abdominal and back muscles. While the baby is napping, take 10 minutes to do stretching exercises on the floor each day. This will help restore hip and back flexibility.
• Try to return to your normal weight within six weeks after giving birth.
  Do not stretch your arms out to pick up the baby. Bring the baby close to your chest before lifting. Avoid twisting your body.
• To pick up a child from the floor, bend at your knees-not at your waist. Squat down, tighten your stomach muscles and lift with your legs.
  Remove the high chair tray when you are trying to put the baby in or take the baby out of the high chair.
• When lifting the child up out of the crib, put the crib side down and pull the child toward you. Do not bend over the crib side and lift the baby over the top.
• Consider using a "front pack" to carry the baby when you are walking.
• Do not carry a child on your hip; this overloads the back muscles.
• To avoid upper back pain from breastfeeding, bring the baby to your breast, rather than bending over the baby. While you are nursing, sit in an upright chair rather than a soft couch.
• Do not stand outside the car and try to place the child in the car seat. Kneel on the back seat as you place the baby into the car seat. Consider trading in your sporty two-door model for a four-door vehicle, which will make it easier for you to place the child in the car seat.
  

If you had a Caesarean-section (C-section) delivery, wait six weeks or until you get the permission of your obstetrician before you begin exercising. Additionally, the risk of back pain is greater among young, overweight women.

(All information on this page is directly from www.aaos.org)