1- The cyclist swerved off the track, then back towards the track;
2- The walker stepped off the track and his feet were immediately run over by the cyclist,
knocking him back to the track and causing him to fall down on the track. He would have been off the track otherwise;
3- The cyclist absolutely caused the walker to fall, and might have caused him to have injuries;
4- The runner tripped on the walker who was knocked back onto the track by the cyclist;
5- The runner did not knock anyone down. The walker was knocked down by the cyclist.
The cyclist should NOT have been riding on the track. I hope he is sued by the walker for damages.
Bicycles absolutely DO damage the track, can wear down the rubber and cause deep ruts in the surface.
I saw this happen to a track in Seattle, where a wheelchair cyclist was going round and round the first lane.
This did cause deep ruts, and the track was destroyed.
The cyclist should be fined for riding on the track, and the walker should be given a warning.
The school needs to post signs and enforce there being NO cyclists on the track, and that walkers stay out of the inside lanes.