The Squat Lift - Ideally, objects should be lifted via the squat lift. With the back relatively straight, the knees are bent so that low back stress is minimized. While this does not seem as easy or natural as simply bending forward at the waist it significantly minimizes the lower spinal stress which can lead to numerous injuries including intervertebral disc herniation. Also, keep the feet wide apart when lifting the object and be sure to keep the object as close to your body as possible.
When Bending The Knees Is Difficult - For individuals who cannot fully bend the knees in order to pick up objects some bending of the spine may be necessary. In these cases, be sure the object being lifting is not heavy and most importantly, be sure to keep the object as close to the body as possible. The farther the object is away from the body the greater the stress on the spine.
The Golden Rule of Lifting - As stated above, be sure to keep objects as close to the body as possible during the lifting and carrying of objects.
Repetitive and Heavy Lifting - Even when proper lifting techniques are used repetitive stress injuries to the spine will occur if objects are too heavy or lifting is done continuously to the point that the spinal musculature becomes fatigued. Never lift heavy objects alone - get assistance or use a dolly. Never lifting continuously to the point that spinal muscles become fatigued. This will dramatically increase the odds of sustaining spinal injury.