I wonder how much of this effect (muscles weaker after stretching) is because stretching tires the muscles, as it will certainly require energy to execute a static for a minute or so. If the effect is similar to other forms of muscle use, it would be unsurprising. If it weakens muscles in a unique way, that seems more interesting.
I stretch quite a bit because my muscles get tighter over the time, in particular from working at the computer.
My dog stretches upon returning to activity from rest. A form of dynamic stretching, just a few seconds.
Central nervous system? As a guess would you say such an effect might not be that bad beyond the immediate lowering of strength? Not a long term effect?
One hypothesis of how stretching increases flexibility is that it's a long term learned effect on the central and peripheral nervous system.
If you try PNF stretching -- where you push back against the stretch -- you'll be surprised how much further a stretch can go. And that's purely a nervous system phenomenon, some of it not reaching the CNS at all.
I stretch quite a bit because my muscles get tighter over the time, in particular from working at the computer.
My dog stretches upon returning to activity from rest. A form of dynamic stretching, just a few seconds.