I am looking for some research that talks about why composite stirrups and wider leathers (not necessarily together) are thought to relieve knee (and other) pain. Anyone got any leads?
There is a lot of anecdotal evidence for it being true (and I believe it), but I am wondering WHY–like what are the physics involved that makes it less painful to have lighter irons and/or wider leathers?
Bonus pints if you can also point me to why jointed stirrups are thought to do similar things. 
Note: I have a pair of MDCs that I bought after I broke my ankle in 2017 and the definitely made it less painful when I was first getting back into the saddle, but I think that was more about the wi
