Tempo Runs Explained — How to Run Them and Why They Work
The tempo run is the most misunderstood session in running — and the most valuable. It is not a race, not an easy run, and not an interval session: it is 20–30 minutes at a "comfortably hard" pace, hard enough to matter and easy enough to sustain, and it does one thing better than any other session: it raises your lactate threshold, the speed at which fatigue starts to accumulate.
This guide explains what a tempo run is, how to find the right pace, the three main formats (continuous, cruise intervals, and progression runs), and how to fit tempo runs into a week without wrecking the easy days around them. If you could only add one hard session to your running, this would be it.
Use the calculator
Start with your own numbers: try our pace calculator, heart rate zone calculator to work out your figures before applying anything on this page. The worked examples below use round numbers so you can follow the maths; the calculators use your real weight, height, age and goal.
Related reading: Easy Runs Explained — Why Slow Running Makes You Faster, Interval Training for Runners — Workouts That Build Speed, How to Run a Faster 10K — Training and Pacing Strategy. You can also browse the full guides section for the rest of the series.
The key points
The tempo run trains your lactate threshold. As you run faster, lactate accumulates in the muscles; the threshold is the pace at which accumulation outruns clearance, and fatigue rises sharply. Tempo running — sustained effort just below that threshold — teaches the body to clear lactate faster and to hold a higher pace before the threshold is reached. That is why tempo pace correlates so strongly with race performance from 5K to marathon.
"Comfortably hard" is a precise feeling. Tempo pace is the pace you could hold for about an hour — hard enough that talking is limited to short phrases, easy enough that you are not gasping. On a 1–10 effort scale it is about 7–8. If you can speak in full sentences, you are running easy; if you can only gasp single words, you are running intervals. The tempo lives in between, and learning to find it is a skill that improves with practice.
Tempo pace is about 15–20 seconds per kilometre slower than 5K pace. A runner with a 25-minute 5K (5:00 per km) should run tempo at about 5:15–5:20 per kilometre; a runner with a 30-minute 5K (6:00 per km) should run tempo at about 6:15–6:20 per kilometre. In heart-rate terms, tempo is about 80–85% of maximum, or Zone 4 in a five-zone system. The pace and the feeling should agree — if they do not, trust the feeling.
The classic format is 20 minutes continuous. After a 10-minute easy warm-up, run 20 minutes at tempo pace, then cool down for 10 minutes easy. That is the whole session, and it is enough: 20 minutes at threshold is a powerful stimulus, and more is not proportionally better. As fitness improves, extend to 25–30 minutes, or split into cruise intervals (2 × 15 minutes with a 3-minute easy jog between) for the same total time with less strain.
One tempo run a week is enough. The tempo is a hard session, and it needs 48 hours of easy running or rest around it — never run a tempo the day after intervals, and never run intervals the day after a tempo. One tempo a week, sustained for two months, typically takes 10–15 seconds per kilometre off a runner's comfortable pace. Two tempo runs a week is possible for experienced runners, but the second one usually costs more in fatigue than it gains in fitness.
The progression run is the tempo's friendly cousin. Start easy and finish at tempo pace — for example, 30 minutes building from easy to comfortably hard over the session. Progression runs are less intimidating than a flat 20-minute tempo, they teach pace judgement, and they deliver a similar threshold stimulus. They are a good way to start tempo training if the continuous format feels daunting.
At a glance
| Format | Structure | Who it suits | Total tempo time |
|---|---|---|---|
| Continuous tempo | 20 min at tempo pace | Most runners | 20 min |
| Extended tempo | 25–30 min at tempo pace | Experienced runners | 25–30 min |
| Cruise intervals | 2 × 15 min, 3 min easy between | Runners who struggle with 20 min | 30 min |
| Progression run | 30 min, easy → tempo | Beginners to tempo | ~10 min at tempo |
| Tempo + intervals | 10 min tempo, then 4 × 400 m | Advanced, race-specific | 10 min + intervals |
Start with the continuous 20-minute format. Move to the extended or cruise formats only when 20 minutes feels comfortable.
The formula behind it
Tempo pace is calculated from a known race pace: tempo pace ≈ 5K pace + 15–20 seconds per kilometre. A 25-minute 5K is 5:00 per kilometre, so tempo is 5:15–5:20 per kilometre; a 30-minute 5K is 6:00 per kilometre, so tempo is 6:15–6:20 per kilometre. The heart-rate version uses maximum heart rate — estimated as 208 − 0.7 × age (Tanaka et al., 2001) — and tempo is 80–85% of maximum. A 30-year-old has an estimated maximum of 208 − 21 = 187 beats per minute, so tempo is about 150–159 beats per minute.
The Riegel formula (Riegel, 1981) connects tempo pace to race performance: if your tempo pace improves by 10 seconds per kilometre, your race paces improve by roughly the same amount, because the threshold is the main limiter for most runners. A runner whose tempo moves from 5:20 to 5:10 per kilometre over two months can expect a 5K improvement of roughly 50 seconds (10 seconds × 5 km) — which matches what coaches observe in practice. The calorie maths is the Compendium (Ainsworth et al., 2011): tempo running at about 6 mph (9.8 MET) burns 9.8 × weight (kg) per hour, so a 40-minute tempo session at 75 kg burns about 490 kcal — but the calories are not the point; the threshold is.
Your plan, step by step
- Find your tempo pace: 5K pace plus 15–20 seconds per kilometre, or the pace at which you can speak in short phrases only.
- Warm up for 10 minutes easy, run 20 minutes at tempo pace, then cool down for 10 minutes easy — once a week.
- Keep the days around the tempo easy or rest; never run intervals the day after a tempo.
- Extend to 25–30 minutes, or split into cruise intervals, once 20 minutes feels comfortable.
- Re-test your 5K every 6–8 weeks and re-calculate tempo pace from the new time — the pace should quicken as you improve.
How to use this guide
Use the tempo run as the weekly test of your fitness. If the tempo pace feels easier than last month, you are fitter — and the pace should be adjusted upward. If the tempo feels harder than usual, you are tired — and the session should be shortened or skipped, not forced. The tempo is honest in a way that easy runs are not: it tells you, every week, where your fitness actually is.
Practise the feeling, not just the pace. Tempo pace is a sensation — comfortably hard, sustainable, controlled — and learning to recognise it by feel is a skill that transfers to racing, where the watch is a guide and the body is the truth. Runners who can feel their threshold pace race better than runners who can only read it off a watch.
What this guide does NOT tell you
Tempo pace guidelines are population averages: the 15–20 seconds per kilometre offset from 5K pace varies with fitness, age and training history, and heart-rate estimates (Tanaka et al., 2001) carry a standard error of about ±10 beats per minute. The lactate threshold is a physiological concept, not a number you can measure without a laboratory, and the pace that trains it is best found by feel and by race performance rather than by formula alone.
This guide is general information, not medical advice. Tempo running is a hard session, and anyone with a heart condition, joint problem or medical condition affecting exercise should check with a clinician before starting it. Chest pain, severe breathlessness, dizziness or sharp joint pain while running are signals to stop and get checked, not to push through to the end of the tempo.
Frequently asked questions
What is a tempo run?
A sustained run of 20–30 minutes at a "comfortably hard" pace — about the pace you could hold for an hour, or roughly 15–20 seconds per kilometre slower than your 5K pace. It trains your lactate threshold, the speed at which fatigue starts to accumulate, which is the main limiter for most runners. It is harder than an easy run and easier than intervals, and it is the single most valuable hard session for most runners.
How fast should a tempo run be?
About 15–20 seconds per kilometre slower than your 5K race pace — for a 25-minute 5K runner (5:00 per km), tempo is about 5:15–5:20 per km. In heart-rate terms, about 80–85% of maximum. The feeling is the best guide: you should be able to speak in short phrases but not full sentences, and the effort should feel like 7–8 out of 10. If you can chat easily, you are too slow; if you are gasping, you are too fast.
How long should a tempo run last?
Twenty minutes at tempo pace is the classic session, after a 10-minute easy warm-up and before a 10-minute easy cool-down. As fitness improves, extend to 25–30 minutes, or split into cruise intervals (2 × 15 minutes with a short easy jog between). More than 30 minutes of continuous tempo is rarely better — the stimulus is strong enough at 20 minutes, and longer tempos cost disproportionate fatigue.
How often should I do tempo runs?
Once a week is enough for most runners, with easy days or rest around it — never run a tempo the day after intervals, and never run intervals the day after a tempo. Two tempo runs a week is possible for experienced runners, but the second one usually costs more in fatigue than it gains in fitness. The tempo is a hard session, and hard sessions need recovery to produce adaptation.
What is the difference between a tempo run and intervals?
A tempo run is a sustained effort at one pace for 20–30 minutes, training the lactate threshold; intervals are short, fast repetitions with recoveries, training top speed and the ability to clear lactate repeatedly. Tempo runs are about holding a hard pace; intervals are about reaching a fast pace repeatedly. Both matter, and a good week has one of each — the tempo builds the threshold, the intervals build the speed that sits on top of it.
Estimates only, not medical advice. Minimum safe intakes: 1,200 kcal/day women, 1,500 kcal/day men — consult a healthcare professional before a very-low-calorie diet.