Tempo run

Plain-English Explanation

A tempo run is controlled hard running. It usually means a sustained effort, or several longer cruise-interval blocks, that sits around the hard-but-repeatable range instead of the all-out range.

The common "comfortably hard" label is useful only if it stays honest. Breathing should be strong but organized, pace should not collapse, and you should finish knowing you could have done a little more if the plan required it. If the first few minutes feel like a race, it is too hot for most tempo work.

Tempo runs often live near threshold-training territory, but a field tempo pace is not the same thing as a lab-measured lactate threshold or ventilatory threshold. Watches, race calculators, and heart-rate zones can give a starting guess; heat, hills, wind, poor sleep, fatigue, medication effects, caffeine, and route choice can all change the real stress.

Use tempo work as one harder ingredient inside a week that still has easy running, steady aerobic work, long-run progression, lifting, sleep, and recovery. Turning most runs into medium-hard tempos is not better threshold development; it is usually just more fatigue with less clarity.

A practical first check is repeatability. If the same route and weather feel controlled for two or three similar exposures, then extending total controlled time is usually a cleaner next step than forcing faster pace immediately. If the next easy run is wrecked, reduce the tempo dose before chasing a sharper split.

Medical context matters because tempo work is vigorous exercise. Chest pain, fainting, unusual breathlessness, new palpitations, known heart or lung disease, pregnancy/postpartum limits, medication effects, recent illness, heat illness risk, or a long layoff can make hard running a clinician-specific question.