radioarno

hi 62 year old here with lots of arthritis, secondary to Ehlers Danlos Syndrome, a genetic condition which produces lots of things, but for our purposes the most significant things are loose joints caused by weak ligaments. The ligaments cannot be strengthened. People like me with Ehlers Danlos have weak connective tissue, the connective tissue *cannot* be strengthened, and ligaments are mostly connective tissue. So here's the quesion: When I started riding lots when I was 16 I had knee pain, and the doctor told me to raise my seat as high as I could. Now, older, not as flexible, and with the requirement that I don't hyperextend my joints because hyperextension exacerabtes the problem, I need to lower my seat. What are the risks of a *lower* seat. What happens to *normal people* when they ride with their seat low?

groth

When you raised the seat, that was to keep the knee as straight as possible, right? Now you need to limit the range of movement of the knee and other joints. I would think you not only need to lower the seat, but also get shorter cranks. (You can get crank shorteners that allow you to experiment with crank length over a small range.)

When I had knee problems and had to use a crank shortener, I was a less effective rider (slower, less steep hills). I suspect this was a combination of the knee pain as well as the shorter cranks.

- Ed

VegasTriker

When I worked in a bike shop a long time ago we were taught to set the seat height so that your leg was still very slightly bent at the furthermost point when turning the cranks. That would give you the maximum effect on pedaling without hyperextending your knees. It's worked for me for decades. When I look at adults or kids riding too small a bike or with the seat so low they ride with a leg half extended I think of how much harder it must be to pedal the bike. The effect of lowering the seat too much is you lose some efficiency but shouldn't result in damage to your knees.