How can I lift without hurting my back?

From Healthwise

Follow these basic rules to protect your back while lifting:

• Keep a wide base of support. Your feet should be shoulder width apart, with one foot slightly ahead of the other (karate stance).
• Squat down, bending at the hips and knees only. If necessary, put one knee to the floor and your other knee in front of you, bent at a right angle (half kneeling).
• Maintain good posture. Look straight ahead, and keep your back straight, your chest out, and your shoulders back. This helps keep your upper back straight while maintaining a slight arch in your lower back.
• Slowly lift by straightening your hips and knees (not your back). Keep your back straight, and don't twist as you lift.
• Hold the load as close to your body as possible, at the level of your belly button.
• Use your feet to change direction, taking small steps.
• Lead with your hips as you change direction. Keep your shoulders in line with your hips as you move.
• Set down your load carefully, squatting with the knees and hips only.

Follow these tips to avoid compressing the spinal discs or straining your lower back when lifting:

• Keep a wide base of support. Your feet should be shoulder-width apart, with one foot slightly ahead of the other (karate stance).
• Squat down, bending at the hips and knees only. If necessary, put one knee to the floor and your other knee in front of you, bent at a right angle (half kneeling).
• Maintain good posture. Look straight ahead, and keep your back straight, your chest out, and your shoulders back. This helps keep your upper back straight while maintaining a slight arch in your lower back.
• Slowly lift by straightening your hips and knees (not your back). Keep your back straight, and don't twist as you lift.
• Hold the load as close to your body as possible, at the level of your belly button.
• Use your feet to change direction, taking small steps.
• Lead with your hips as you change direction. Keep your shoulders in line with your hips as you move.
• Set down your load carefully, squatting with the knees and hips only.

Keep in mind:

• Do not attempt to lift by bending forward. Bend your hips and knees to squat down to your load, keep it close to your body, and straighten your legs to lift.
• Never lift a heavy object above shoulder level.
• Avoid turning or twisting your body while lifting or holding a heavy object.