Thanks Bernard for looking in to this, I'm a walker and a cyclist who likes routes to be correct, so is much appreciated.  
Area was visited this week (Tuesday) and between Blackbrook Farm and Forest Lane is a ploughed field. There is no path, and walkers and cyclists wind up on the adjacent busy A road.  The entry on the map for Charnwood Forest Line is the route of a discontinued railway. Some of it is a viable path (Jubilee Way), much is not.  Following the route (Whitwick)  it can be seen to run through houses and back gardens. It may have been added to OSM for historical study  purposes  but is not a viable path, indeed the farmer has put up a sign to that effect. The latest OS map also confirms this.  
The line is a historic railway route but is not a footpath or (cycle) track.

Thanks again for the response, I can visit the area and take pictures if is helpful   