Where the zones come from
Your race gives a measure of your fitness, worked out with the formulas the coach Jack Daniels and the physiologist Jimmy Gilbert published. Each zone is a share of it. Easy running sits around two thirds of it, marathon pace around four fifths, and the hard repeats of zone 6 at all of it.
These are the same seven zones the Strides app sets up from your race, with the same names and the same rounding, so the paces here are the paces you’ll see in the app.
How to use them
- Most running is easy. Zones 1 and 2 should carry most of your week. Easy days are what let the hard days be hard.
- The middle zones are for specific work. Steady and marathon pace belong in long runs and marathon training, not in every run.
- Hard work comes in doses. Threshold, zone 6 and zone 7 are run as repeats or set efforts with rest, a couple of times a week at most.
- A range, not a target. Run the slower end on hills, in heat and on tired legs. Pace drifts with the conditions, and effort is what you’re training.
When to change them
Update your zones whenever you race, or after six to eight weeks of steady training. If the paces you’ve been given start to feel easy, that’s fitness, not luck. Strides does this for you: it reads every run and tells you when your easy pace has moved, so your zones never fall behind your fitness.
Questions
How fast should my easy runs be?
Slow enough that you could hold a conversation the whole way. For most runners that’s somewhere between one and two minutes per mile slower than their 5K race pace. Zone 2 above gives you a range from your own race.
Why base zones on a race and not my heart rate?
A race is the most direct measure of how fast you can run. Heart rate zones are useful too, especially in heat or on hills, where the same pace costs more. Many runners use pace for workouts and heart rate to keep easy days easy.
How often should I update my pace zones?
Whenever you race, or every six to eight weeks of steady training. If your workouts start to feel easy at the paces you’ve been given, your fitness has moved on and it’s time to update them.
What’s the difference between threshold and tempo pace?
They’re usually the same thing: a comfortably hard effort you could race for about an hour. Coaches use the names differently, so check the pace rather than the word.
Sources: Daniels, J. and Gilbert, J. (1979), Oxygen Power: Performance Tables for Distance Runners. Daniels, J., Daniels’ Running Formula, Human Kinetics.