Assuming that you have spent the effort to develope more control over IAP (intra-abdominal-pressure, see here), or that you were gifted with the inherent ability to control IAP at will, which is the basic fundamental skill that must be applied to all of the exercises geared towards strengthening the lower back; the following entry is the intermediate stage on 'how to build a stronger lower-back".
The head, neck and upper body as one single cohesive structure is like a big ol'tree with its crown, trunk and roots. For the tree to have a full crown of leaves, ubiquitous branches and a thick sturdy trunk, the tree must have roots firmly anchored into the soil. Likewise, for the neck to be strong and to withold the weight of the head, its roots (the trapezius muscle and others, image below) must also be strong. As shown, the trapezius muscle is posterior portion of the root that supports an upright posture of the body. It is a thick and large piece of musculature that spans from the base of the skull to the shoulders and latches onto the spine. The middle and lower portion of the trapezius muscle each draws the shoulder blade backwards and downwards towards the spine. Amongst those with a weak neck, the said muscle (along with the deep neck flexor described in the previous entires) is most often the weakest link, and in this entry, we will be talking about strengthening of these two portions of the trapezius muscle. Further, the strengthening of this muscle group should be an advanced routine that follows the deep neck flexor exercise mentioned here, with the purposes to build a stronger neck and upperback.
In order to build a stronger and healthier neck, one must understand 4 crucial structures of the cervicothoracic anatomy, as is described in the image above. The cross indicates 4 muscle groups, each located in the 1)upper frontal, 2)lower frontal, 3)upper rear and 4)lower rear quadrants acting as tension cords that anchors and pulls from the base of the neck to maintain an upright posture (base of the neck). Thus, it is given the pictorial name to the anatomical junction, the "upper-cross".
Ever since a very young age and being the avid computer gamer that I am, I've spend a chunk of my life in front of the monitor. For a very long time, I've been troubled with frequent neck pain and pounding headaches, and it wasn't until getting into chiropractic school that I then understood the condition can actually be treated. Interestingly, most people feel that postural pain is inevitable and we should just learn to live with it. That's just not true.
It would be convenient to picture the intra-abdomen cavity as a barrel-shaped container with nothing but air, but of course the abdomen is filled with vital organs and tissues leaving very little space for anything else. Nonetheless, and for the sake of biomechanics, let's imagine the intra-abdomen with just the skeletal frame, muscular sheaths and an air-tight skin layer.
In this routine, we are going to use pressure to strengthen the lower-back. The shape and structure of our trunk allows us to pressurize from the top, bottom and sides of the abdominal cavity causing the walls of the abdomen to stiffen up and thereby producing rigidity across the entire lower torso (including the spine). This multi-faceted compression thus create the very foundations of lumbar spine core stabilization.