Hi, I'm using a JVC HD7 which (with a bit of effort records to Mpeg2) and a Sanyo HD1 which records to MP4.
MP4 is useful because it is highly compressed and because the Sanyo uses SD cards so file size is at a premium. The negative is that the higher the compression the lower the quality.
I use the JVC for "serious" work and the Sanyo for "Fun" i.e. hangs onn a suction bracket on the bonnet of my car, mounted into a grass tracking Mini (on race days) etc.
The solid state of the Sanyo reduces the risk of internal damage.
Summary, for sports use any solid state camcorder will do (but it will record to MP4) but if you intend treating it gently go for a HDD or mini-disc camcorder recording to mpeg2.
Hope it all makes sense
Regards

Tony