Final answer:
True, good body mechanics for lifting involve bending at the hips and knees, which helps to maintain proper posture, minimizes back strain, and effectively distributes lifting forces across the legs.
Step-by-step explanation:
The statement that good body mechanics includes bending at the hips and knees when lifting is true. Proper lifting techniques are fundamental for maintaining good posture and preventing back injuries. When lifting, keeping the back erect is essential to avoid excessive force on the spine.
By bending at the hips and knees, the body maintains a better center of gravity and reduces the risk of strain as forces are better distributed across the muscles of the legs, not the relatively weaker back muscles. This method minimizes the forces acting on the back, which can be about 5.6 times smaller than when lifting incorrectly, effectively protecting the spine and reducing the risk of injury.