Heart rate– If you know your maximum heart rate values or threshold values then it is easy to work backwards to determine an appropriate effort for different events or workouts. See Table 1 to identify what effort you should be at for what type of event.
Pace– If you know your goal pace and it fits within the appropriate effort range then go by pace (but remember that pace can be affected by wind and terrain so it is not always the best measure unless all other factors remain constant)
Perceived (Scale 1-10)– Perceived effort can also be used to determine how fast you can go. Some people have a much clearer understanding of how hard they can go for what distance. There are some easy ways to gauge how hard you are going. A simple measure out of ten is a good place to start. For a marathon you can be anywhere from a 6-8.5 out of 10 depending on your level of experience and your level of fitness. Remember also that the longer the event will take you the lower on the scale you should be in order to make it to the finish line. Remember that in longer events a 6.5/10 in the first two hours will probably feel more like an 8/10 in the last two hours so pacing is very important.
Perceived- At B78 we also use the terms “Easy, Medium, Hard, Really Hard” or “Slow, Medium Pace, Fast, Max Effort” to determine effort and for some people this is enough. Easy would be a pace that you may start a warm up with, Medium would be the pace you would run a marathon at if you are just trying to finish and will take longer than four hours. Hard is a pace you could sustain for 1-2 hours depending on your fitness and Really Hard is a pace you can sustain for several minutes at the end of which you are completely done!