It's not the treadmill. It's the unweighting.
Muscles have memory patterns that are established by the nervous system. The more we utilize the muscle pattern, the easier the muscles coordinate to accomplish this task. Whether it is signing our name, dribbling a basketball, a tennis serve, or just walking we are constantly using these muscle patterns. We memorize these patterns but just because it's memorized doesn't mean it's properly working.
Changing or improving those patterns can be difficult. Ask the golfer who doesn't break 100. So how do we change a pattern for the better? It's called neuromuscular re-education. Neuro (the brain and nervous system) needs to recognize the new or improved pattern. When we reduce the effects of gravity with the unweighted system our brain (the vestibular system) has to adapt to this change. This adaptation challenges the nervous system, which is how we orient our bodies while standing, walking, and running.
So why is this important in our walking? The more inefficient our gait or stride, the harder we have to work. Eventually these inefficient patterns create an overload of some of the muscles being used for the task. These muscles cross joints, when they become tight due to the overload, the joints get compressed causing a fixation or lack of mobility. This process becomes a self-perpetuating cycle, which can go on for months or even years before the body sends us a warning signal. This is the cycle which initiates the degenerative process (osteoarthritis).
The unweighted treadmill is important in the process of stabilizing the pelvis (the foundation of your body), improving our stride (a more efficient walking pattern), improving our balance, and improving posture. Wow! What a bold statement! Yes, it does that and more. So why is it important to stabilize your pelvis? No matter where your aches and pains exist the pelvis is our foundation. Rather we have pelvic instability, pelvic twisting, a muscle imbalance, or a lack of normal function this always results in something else working extra. Usually it's the muscles above or below the pelvis. When these muscles become overworked the joints become irritated.
When the stress level of the joints and muscles become severe enough and the body can't adapt, we get the warning signal. This signal can present itself as pain, numbness, or tingling. These are the signals our body gives to tell us there is something wrong and its important to listen to our body. The pain isn't the problem, it's just the signal. Our goal is to first identify the problem and then treat the pain (our signal of the problem.) Once the pain subsides, we focus on removing the dysfunction in our kinetic chain by decreasing the effect of gravity with the unweighted treadmill and let the brain more easily connect to the muscles restoring our movement patterns for longer lasting results.