Back Strength
The back muscles become vulnerable to injury as we age for a variety of reasons, although the most common reason is misuse. We rely on our backs to do the majority of lifting and twisting in our lives, and yet we rarely take the time to strengthen them. Somehow, we think of our backs as sensitive, and yet rarely take the time to relax them. We force our backs into unhealthy, awkward positions (sitting in chairs, chief among them, but lying on couches and beds that are too soft are also problems), and then get frustrated when our backs aren't as strong as we would like. Even dedicated exercisers often ignore their backs because they can't see those muscles when they look in the mirror.
Humans are born with thirty-three separate vertebrae. By adulthood, we only have twenty-four, due to the fusion of the vertebrae in certain parts of the spine during normal development. Strengthening the muscles of the back helps keep the spinal column strong, too, which reduces the chance of back pain.
The Spinal Column
The spinal column and vertebrae protect the spinal cord, which provides communication to the brain, mobility, and sensation in the body through the complex interaction of bones, ligaments, muscle structures of the back, and the nerves that surround the spinal cord. The back is also the powerhouse for the entire body, supporting our trunks and making all of the movements of our head, arms, and legs possible.
The small muscles deep in the back play an important role in controlling the joints between the vertebrae of the spine. They steady the spinal column so that the long muscles of the back can use the spine as a lever when bending and twisting the torso. These muscles are therefore also important to posture.
Core Flexibility
One interesting piece of information personal trainers know and gym-goers don't is that gym injuries happen when people are picking up or putting down weights, not when they are doing exercise. The reason for this? Most people aren't flexible enough to properly move their weights around, even if they are strong enough to lift them. Twisting to put weights on the floor is hard for most of us, just as it is difficult for people to twist toward the backseat of their car or reach up high over their head.
Although strength is often thought to inhibit flexibility (strength shortens a muscle, making it difficult to stretch it) the reverse is true of a strong core, because it helps to be able to rely on the stability of your abs and back in order to lengthen and turn your limbs and torso. Think of ballerinas, gymnasts, and skaters. In general, they have the strongest cores of all athletes and, of all athletes, they are also the most flexible.
