Muscle "tightness" - what is actually happening?

Forgive me if this has already been asked, but I suck at google and couldn’t find it.

I understand that myofascial release is voodoo nonsense, that foam rolling doesn’t work, etc. My question is, when I get a massage or foam roll, what are the firm spots that, when pressed, I can feel through what appears to be the respective muscle, and soften after a few minutes? Why does the respective area feel “loose” and less painful afterwards? Maybe a silly question, but I haven’t been able to find any info on if it’s actually the muscles themselves relaxing or some other mechanism (or placebo)

thanks in advance!

microwavetechnician - thanks for the questions. These outcomes you are identifying are typically related to expectations and conditioning (e.g. placebo like contextual effects).

I’m not sure I understand. For example the hard “tense” muscles I can feel during a massage - they go soft because of placebo? Or do you mean that placebo makes them feel softer when nothing has actually changed?

I’m not referring to any kind of myofascial thing, I specifically mean the muscles themselves. I’m also not talking about mobility since I know that isn’t really a thing either. Are the muscles actually “relaxing” as the voodoo would have me believe?

In this regard, palpation (feeling the muscles) isn’t a reliable approach given the premise is “I feel something” (A) + “I do something, massage.” (B) = C (“The something I felt ‘feels’ differently.”) and somehow that’s meaningful. Expectations and conditioning are reasons for why you may feel something differently and then become a bit focused on that something unnecessarily leading to future engagement of “X” behavior, massage. In other words, we are making something out of likely nothing and usually these “tense” muscles aren’t conscious to us until an outside observer makes claims of their existence or we just go feeling around. It’s normal for areas to feel differently once our attention becomes focused on the body region or is drawn to the region. This isn’t negating you perception of feeling something but rather asking the question how important is this really. We can certainly entertain ourselves into thinking we feel all sorts of “somethings” and then label them as say “knots” or “tense” muscles then rationalize interventions, we wouldn’t recommend this approach overall. Hopefully this provides some clarity.