Originally Posted by
koala logs
Based on that article, we should be using significantly shorter crank length (I'm actually in favor of this), and avoid putting down power, hence loading your knees at the top of the pedal stroke where the knees are bent at the most degree. Of course, that can be fixed with shorter crank.
Note that load is also a factor here, not just the bend. One way to reduce strain on the knees is allocate some of the downstroke force to your glutes as well so the load is distributed more evenly between the knees and the hips, and not concentrated on the knees. Don't depend mostly on the quads to push down the pedals.
Having small, undeveloped glutes can be a bad sign you're putting most of the pedaling load on the quads and hence, the knees.
I agree, there are definitely different pressures put on the knee at various angles of bend; however, I would rather address this issue with weightlifting and leave my bike at whatever crank arm length, seat height feels best for my body.
This way I can focus on using exact weight to judge what's too much for my given knee strength and improve from there; furthermore, I can build up my knees far stronger than I can on a bike, since cycling is primarily an aerobic activity. And of course, I can also bend my knee much further for greatest strength and flexibility thru the entire natural motion of the knee (or whichever joint I'm working). This way I have zero problem with respect to my knees regardless of seat height, crank arm length or whatever I choose to ride, based on my personal physical frame.
And of course there are other reasons to lift weights...strengthen bones, especially the spine, since it seems we cyclists lose a lot of muscle density in that area, again, because cycling is low-impact, non-weight bearing activity.
BTW, when I say weightlifting, I'm not including machines, since most of them you do in a seated position, hence, not weight bearing, such as when you use old school barbell and weights doing things like squats, deadlifts.....
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