Notes
4 x 2:50ish on the sloping field behind the Madingley Hall spinney (not the sledging field), off 40 secs, moderate intensity; then 6 x 20 secs decent strides off 20 secs jog recovery along the concrete fm track.
Getting dark - amazing evening, really, after very warm day - very still, and the tops of the slopes are in warm, humid air left from the afternoon; but suddenly you step down across a temperature divide into the cold night air at the slope base.