If you know you will be standing for an extended period, make sure that you wear supportive shoes and make sure you know how to keep a good posture. Good posture is the key to a healthy spine. Keep your chin up and your shoulders back. Keep both feet about shoulder-width apart.
Working at a Desk
Make sure that you are getting up every 30 minutes to stretch, even if you just walk around for a few minutes. Next, be sure you are seated correctly. Make sure you have a chair that offers good lower back support. You also want your feet flat on the floor with your knees at a 90 degree angle. If you need a stool under your feet to do this, bring one to work. Your computer screen should be at eye-level, so you are not looking down at it.
Lifting objects is one of the most common ways to injure yourself. Start by squatting down to the object with one foot slightly in front of the other. Keep your back straight, only bending at the knees and hips. Keep your head looking forward and lift the object by straightening your legs, still keeping your back straight. Hold the object close to your body. Never twist while picking something up. Only turn once you are fully upright. Keep the same idea in mind when you are putting the object back down.