Training for endurance requires your body to work hard but to see improvement, this has to be done without you getting ill or injured. You therefore need some recovery runs and these should be run at a very easy and relaxed effort. You should be breathing easily and be capable of holding a conversation throughout the run. Elite athletes will run 70- 80% of their running at this Easy effort (thats around 70 - 80 miles a week), and most of the time they wont care what pace is coming out.
We often get asked if there is a difference between Recovery and Easy running, and in short Yes there is.
Recovery Running; The aim of a recovery run is just that recovery. You should feel better at the end of a recovery run than you did at the start! It should be refreshing. The pace on this sort of run really does not matter. If you are finishing recovery runs panting, sweating and out of breath then you are running too hard. Your effort level should be at around 6-6.5 out of 10 (60–65% HRR) and your run should be no more than 45 minutes in duration, otherwise it isn’t really recovery.
Easy Running; The difference with an Easy Run is you might work towards a 7 out of 10 on this sort of run, working a bit harder than a Recovery Run. The aim of this run is to build endurance and weekly running volume. These sorts of runs can last anywhere from 30 minutes to over an hour.
The effort level on these runs is totally conversational!
Never be afraid to run easy, and don’t worry about the pace you are running.