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CalculatorTraining pace calculator
One recent race gives you all five training paces — easy, marathon, threshold, interval and repetition — and the calculator corrects them for where you train. Johannesburg runners: your paces should be about 8% slower than a sea-level chart says.
| Pace | Target | What it is for |
|---|---|---|
| Easy | 6:51–7:50/km | Most of your running. Conversational; slower is fine. |
| Marathon | 6:10/km | Long-run finishes and race-pace practice. |
| Threshold | 5:49/km | Comfortably hard. Repeats of 8–20 minutes. |
| Interval | 5:16/km | Hard. 3–5 minute reps with equal jog recovery. |
| Repetition | 4:55/km | Fast and short, 200–400 m, full recovery. |
Five paces, five jobs
Easy running builds the aerobic engine at a cost you recover from by tomorrow, and it is most of a good week — roughly 80% of the time. Threshold is comfortably hard, about what you could hold for an hour, and it is the most productive harder pace there is. Intervals are hard three-to-five-minute efforts for VO₂max. Repetitions are short and fast, for speed and economy. Marathon pace is for long-run finishes and race practice.
The commonest mistake is not the hard days. It is running easy days too fast, so the hard days are done tired and the whole week turns grey. The easy figure here is a ceiling: slower is fine, faster is the mistake.
Why altitude changes every number
There is less oxygen in every breath at altitude, so the same effort produces a slower pace. Race Shape slows paces by roughly 2% for every 300 m above 500 m — about 8% in Johannesburg at 1 753 m. Train to a sea-level chart in Gauteng and you are running every session too hard. Pick where you train and the table corrects itself.
These paces, in a plan
A pace chart tells you how fast. It does not tell you which session goes on which day, how much of it, or when to back off. A Race Shape plan uses exactly these paces and lays them out over every week to your race, with a lighter week every fourth and a taper timed to race day.
Common questions
How fast should my easy runs be?
Slower than most runners run them: for a 25-minute 5 km, no faster than about 6:19/km at sea level, 6:51/km in Johannesburg. It should feel conversational. Why.
What is threshold pace?
Roughly the fastest pace you could hold for an hour — hard but controlled. It is usually trained in repeats of 8–20 minutes. More.
Do I need to correct for altitude?
If you train above about 500 m, yes. In Pretoria the correction is about 5.6%, in Johannesburg about 8.4%. If you race at the coast, the same effort will be quicker on the day.
How often should I update my paces?
After any race or time trial that was a genuine effort, and at least every six to eight weeks in a training block.
Put this calculator on your club’s website
Free for running clubs, coaches, race organisers and bloggers. Copy the code below into any page that accepts HTML — WordPress, Wix and Squarespace all do — and your members get the same live training pace calculator, with nothing to install and no sign-up.
Keep the credit line under it, please: that is the only thing we ask in return.
Related
Build a plan with these pacesFree to build. See your whole block before you pay.