Full flexion of the lumbar spine puts the ligaments, discs, and muscles at a disadvantage. The ligaments are in a fully stretched position when the spine is bent forward all the way. The discs are placed under a loading and shear force that can cause damage, especially with repeated movements.

And when the spine is fully flexed, the muscles in the low back that extend the spine are at a mechanical disadvantage. In this position, the lumbar extensor muscles can't help reduce shear forces on the spine. This puts the spine at increased risk of injury.

NZ exercises move the body through various positions while keeping the lumbar spine in neutral. When in a proper neutral position, the pelvis can tilt in equal amounts of flexion (bottom tucked under) or extension (swayback position).

Physical therapists are trained in teaching this type of exercise. Sometimes it is referred to as a neuromuscular training or motor control program.