Degenerative Achilles tendons have reduced stiffness.

On yesterday's podcast 127 recording (launch in 3 weeks), we go down this rabbit hole. A worthy hole.
This is important stuff, if you are treating people, (unlike Joe Rogan and the Scibabe, soft slap there, they should use their platform to interview really smart people when it comes to medicine :), you need to know this stuff.

"Achilles tendon, when degenerated, exhibits lower stiffness. This local mechanical deficit may be compensated for by an alteration of motor commands from the CNS. These modulations in motor commands from the CNS may lead to altered activation of the agonist, synergist and antagonist muscles. "