This is a question I get asked quite a bit at this time of year.
First, it is important to remember that hard or easy are terms that work for everyone, whereas fast or slow are terms that are relative to the individual. An effort of 65% is the same for everyone, but probably different paces for most.
The guiding principle is the harder you go, the shorter the duration, and the easier you go, the longer you can maintain it. Seems logical enough, I hope.
As a general rule, effort works better than pace when it comes to certain workouts, and pace works better for specific individuals and their workouts, assuming conditions are appropriate.
It is also really important to remember the human body is not a computer program where one missed input ruins everything: something close to the right pace or effort is usually fine. You can push a bit harder to run with someone, or you can back off a bit to stay with them. It’s all good.
With all that understood, I often use effort as the main determinating factor because it works for everyone, in all conditions.
65% for a long outing should feel pretty relaxed and easy. This would also be quite sociable.
65% for a short outing might feel boring or unfulfilling, but is definitely extremely sociable.
75% is reasonably comfortable for most outings but tough near the end of a long run.
85% for a long run would be close to a race and may not be sustainable until the end. Definitely a quiet run if out there with a partner or few.
85% for a short outing may be a challenge, but is absolutely attainable. It could be thrilling and invigorating.
95% is only sustainable for a short period of time, like about 5min. Yes, that short. you save that for interval workouts and any time you feel like winding things up, but with less than 5min to go.
More specifically, the answer to ‘How hard is hard, and how easy is easy?’, depends on a few things:
1. how far or how long (time) the effort will be maintained
2. how much total volume, and
3. how much rest will be incorporated into the workout.
This overall philosophy holds true for interval workouts as well as regular runs, but the range of efforts gest tighter: 85%, 88, 90, 92, 95, etc. Even though the term hard may be used, there would be a difference between a hard 2min hard piece and a hard 5min piece.
Additionally, the total time of the hard work in an interval workout has a bearing on the actual intensity: 10x2min hard may equal 20min, and 2x5min only equals 10min. But since 10min is shorter than 20min, the 5min pieces would likely be harder than the 2min pieces, or at least the same effort.
And then there is the recovery between the intervals--the more rest, the harder the effort. the less rest, the easier the effort.
As an example, 10x2min hard with 2min rest should be really hard, whereas 10x2min with just 30sec rest would not be as hard. You can’t go hard if you are not well recovered. Certainly not for 20min worth of work.
A benefit of using effort as a guide is that it is reasonably independent of conditions--wind, snow, uphill or downhill can all be done at a consistent effort, but running the same pace in the snow or uphill is not the same as in good conditions. There should be a certain allowance for that.
Another benefit is that we are not always “on”, so hard on one day may be different than hard on another day. Going by effort gives a bit of leeway.
The next question to ask is “What the heck do the other terms, like easy, tempo, up-tempo, hard and really hard mean?”
That’s a great question!
Easy = 65% = 30-40sec slower than marathon pace (assuming you have one)
Tempo = 75% = marathon/half marathon pace
Up-tempo = 85% = 10k or half marathon pace, and if really fit, marathon
hard = 85-90% = 5k or if really fit, 10k pace
Really hard = 92-95% = if super fit, 5k pace
Okay, that’s it for this edition.
Next time, I will touch on an equally important question (s): “How hard is too hard and how easy is too easy?”
In the meantime, I hope this helps.