"I keep coming across examples of karate people needing hip or knee replacement surgery. But I wonder if that is genetic propensity or just normal wear and tear that over time, whatever type of lifestyle the individual was leading, would have reached a natural crisis point?"
I was very fortunate to come across Jesse Enkamp's blog on this subject, and Herman Bayer's book "Genuine Karate", as both taught me how to prevent getting a metal knee replacement when I'm older In the interest of saving the knees of practicing karateka/other martial artists reading this:
'The optimal posture is only to be achieved by aligning the bending direction of the knee joints with foot position vectors, which is, in short, placing "knees over the big toes". This aligns the bending directions of both joints, knees, and ankles, without creating any harmful torque on knee joints when getting lower.'
TL;DR Your knees are meant for bending, bending them is not inherently harmful. However, don't bend them weirdly or you might hurt them ;_;
They are right about alignment. I think with smarter training instructors tend to be on the lookout for this. If it's going wrong it's probably revealing another weakness in the student's positioning, for example; if the foot is out of position, then the knee is also likely to be out as well, and tracking further up the body it might reveal that the hip alignment is also out. But you need a keen eye to be able to spot it.
"I keep coming across examples of karate people needing hip or knee replacement surgery. But I wonder if that is genetic propensity or just normal wear and tear that over time, whatever type of lifestyle the individual was leading, would have reached a natural crisis point?"
I was very fortunate to come across Jesse Enkamp's blog on this subject, and Herman Bayer's book "Genuine Karate", as both taught me how to prevent getting a metal knee replacement when I'm older In the interest of saving the knees of practicing karateka/other martial artists reading this:
'The optimal posture is only to be achieved by aligning the bending direction of the knee joints with foot position vectors, which is, in short, placing "knees over the big toes". This aligns the bending directions of both joints, knees, and ankles, without creating any harmful torque on knee joints when getting lower.'
TL;DR Your knees are meant for bending, bending them is not inherently harmful. However, don't bend them weirdly or you might hurt them ;_;
They are right about alignment. I think with smarter training instructors tend to be on the lookout for this. If it's going wrong it's probably revealing another weakness in the student's positioning, for example; if the foot is out of position, then the knee is also likely to be out as well, and tracking further up the body it might reveal that the hip alignment is also out. But you need a keen eye to be able to spot it.
I'm certainly trying to get "softer" as I age. I'm already pretty soft, though! My style is uber-lazy.