On a cycle: tough call, I split my chin open riding my trike when I was around 3, tried to ride it down a short set of steps. Have scars from the stitches in my chin 32 years later. As a teen, I ate it going downhill on my 10 speed, was wearing flip-flops, foot went into front spokes, hit the forks and I went over the handlebars. The pain was excruciating. I chewed my big toe to #$%$ and broke it too, bruised myself in a bunch of places from that one, too.
Not cycling: I'm notoriously clumsy but lucky, I've never broken a major bone but I've broken several toes. My most recent nasty injuries were either that day last summer when I got hit by a cyclist (oh the irony) then I fell down a flight of stairs on my rear end...on the same day. I missed up my rotator cuff, bruised my @$$ so bad I couldn't sit properly for a week and had a nasty bruise on the side of my forearm that had a huge lump on it. I had the ugliest bruises for weeks after that. I missed a day of work, too.
About 3 years ago I fell down walking down a hill, there was dirt worn away from the edge of the sidewalk and I stepped there and rolled my ankle really bad, down I went and because it was downhill, couldn't save myself from hitting hard. I was overweight at the time, too. Bruised and scraped up my knee, shredded my ankle and bruised/chewed my elbow. I had to get a tetanus shot (I was not amused by that) and my ankle wasn't right for years. It used to ache sometimes.
I was amazed at how badly you can chew your body up just taking a dive walking.