What each pace is for
- Easy
Most of your running, including long runs and recovery days. You should be able to talk in full sentences.
It is a range because easy pace moves with sleep, heat and yesterday's effort. On a bad day, slower is fine.
- Marathon
- The pace your 5K says you could hold for a marathon, if you have trained for it. Marathon plans use it in marathon-pace runs and some long runs.
- Threshold (tempo)
Comfortably hard: about the pace you could race for an hour. Run it as a steady 20 minute tempo.
Or as repeats, such as 4 to 5 x 1 mile with a minute's easy jog. It raises the pace you can hold before slowing.
- Interval
Hard: about the effort you could hold for 10 to 12 minutes. Run reps of 3 to 5 minutes, such as 5 x 1000m.
Jog recoveries last about as long as the reps. This is the session that raises your aerobic ceiling.
- Repetition
Fast and short, 200m to 400m, with full recovery. It is about speed and good form, not breathing hard. Daniels sets it 6 seconds per 400m quicker than interval pace.
Keep the reps crisp rather than straining for the last few.
How much of each
Easy running should be most of your week. Jack Daniels' rule of thumb keeps threshold work to about 10% of weekly mileage.
Interval work stays near 8% and repetitions near 5%.
Two hard sessions a week is plenty for most runners. Put an easy day between them.
Which race time to use
Your paces are only as good as the time you put in. A good input is:
- Recent, from your current spell of training. An old best describes someone you used to be.
- All-out, a real race effort, not a training run.
- On a flat, accurate course, without heat or a strong wind slowing you down.
- From 5K to half marathon. A mile can overrate your endurance, and a marathon can underrate your fitness if the last few miles went wrong.
No recent race? Run a solo 5K time trial on a flat route after a proper warm-up. It will probably be a little slower than a race, and slightly cautious paces are better than paces you cannot hit.
Keep the paces honest
Use a recent race you ran hard, not a goal time. Train for where you are, and the goal comes.
Run a new 5K or parkrun every 4 to 6 weeks, and move to the new row when you are faster. Do not change rows because one session felt easy, or because one felt hard after a bad night's sleep.
In heat, at altitude or on hills, run by effort and let the pace slip.
Pace, heart rate or feel
Pace is precise and easy to check, so use it for structured sessions on flat ground. On easy days and in bad conditions, check yourself with the talk test: if you cannot speak in full sentences, slow down.
Heart rate can help keep easy days easy, but formulas like 220 minus age can be well off for any one person, wrist sensors can be unreliable, and heart rate drifts up in heat and on long runs.
Where the numbers come from
Every figure here comes from Jack Daniels' VDOT equations in Daniels' Running Formula. The same code sets the paces in every Run-R plan.
They estimate what your fitness supports. They are not a test result.
The VDOT chart shows the race times for each score. The 5K pace chart gives race pace and lap times for any 5K goal.