Ok, so maybe aggressive stretching isn't the answer to muscles being tight, and I've delved into some alternative methods for helping to increase flexibility in the past, but why do muscles get tight in the first place?
Does tightness occur simply due to high amount of use? True, muscles may become stiff when they become conditioned to high demand, such as your spinal muscles or the calves of runners, but let's make sure we realize that stiffness is one thing and that the sensation of a muscle being tight is another.
For the record, muscles require stiffness to function and that stiffness should not be a cause for discomfort. If you disagree, go ahead and try to loosen up your neck and come let me know how it's working for you if you achieve it.
For this reason, I try to avoid even using the word "tight" when in practice, as it sends the message that any tension and stiffness is a negative thing. But if we were loose all over, we'd be pretty useless meatsacks.
So when things DO feel tight, what's happening? Well, that is usually due to muscle tone.
We now understand that flexibility is a mechanism driven by the nervous system and has to do with the level of passive contraction that the muscle is holding when at rest. That level of contraction and tone will change based on the body's physical condition, work demand, and also simply by what it's trained to do.
"Tight" muscles occur when the nervous system is given a reason to hold an excessive amount of tone. These reasons can include acute injury, of course. However, they can also include the muscle simply not being strong enough to do it's job, resulting in increased tone to compensate. This being said, when I find a particularly tonic and tender muscle on a client, while I do treat it for that tension, my immediate next step is start exercising it. (Not stretching it!)
If we can understand the messages that our bodies send us, then it helps us to remedy the discomfort that we are in much more effectively. Targeting the symptoms of tightness often gives us some relief, but mindfulness about addressing those root causes is equally or more important.