I've been working on some intervals .I did 2 x 3 minute runs today and 2 x 2 minutes over a 4 miler .The rest moderate to fast pace . I used to get intervals mixed up with sprints .This article is pretty good .I have started doing a bit of running backwards and that as well .Got to admit I hate running but it's better when u mix it right up . http://www.bodybuilding.com/fun/ss11.htm
