What is a tempo run: the threshold session that decides your race pace.

Why the tempo confuses so many runners

In 15 years of coaching, about seven out of ten intermediate runners I meet either run their tempo too fast or skip it entirely because they are not sure what one is. Both mistakes produce the same race: a decent first half, then a slow, confused second half where the pace they hoped to hold quietly leaves them.

The tempo is not a hard run. It is not intervals. It is not race pace. It is the single most productive session for anyone racing from the 5K to the marathon, and the one that most self-coached runners either miss or corrupt.

Here is what a tempo run actually is, how to pace it honestly, and the three formats I cycle athletes through in a full training block.

What a tempo run actually is

A tempo run is a sustained continuous effort at or just under your lactate threshold. Threshold is the highest sustained pace at which your body clears lactate as fast as it produces it. Push above threshold and lactate accumulates, breathing gets ragged, and the clock starts ticking on how long you can hold on. Sit at threshold and you can hold on for roughly 45 to 60 minutes before form starts to compromise.

For most runners, tempo pace is somewhere between 15K and half-marathon race pace. If you have never raced those distances, use the talk test: a tempo effort is where you can speak a four-word sentence between breaths but not carry on a conversation. That capacity is what shows up on race day, when the mile splits go quiet and the effort stops feeling free.

The physiology, in one paragraph

Under threshold, slow-twitch fibers run the show and lactate clearance keeps up with production. As pace climbs, more fast-twitch fibers get recruited, lactate spills into the blood faster than the mitochondria can shuttle it back into fuel, and hydrogen ions accumulate in muscle. That is the burn, and the reason pace suddenly feels unsustainable. A tempo run trains that exact shift point higher, so on race day your steady-state pace is 5, 10, or 20 seconds per mile faster than three months ago. It is the highest-return single workout in road racing, which is why every serious coaching tradition has some version of it.

Three ways to find your real tempo pace

The three methods I use, in order of trust:

1. A recent honest race. If you have a 5K, 10K, or half-marathon time from the last 8 weeks, plug it into a VDOT calculator and read off threshold pace. The VDOT approach gives you a full pace set from one effort, and its threshold estimate is the most reliable non-lab number I know.
2. The talk test. No watch, no data. On a mid-run pickup, run until you can only speak in short phrases. If you can hold a conversation, you are still easy. If you cannot get a full sentence out, you are already above threshold. Tempo is the narrow band in between. This sounds imprecise. It is more accurate than most heart rate estimates.
3. Heart rate as a check, not a target. Roughly 85 to 88% of max heart rate for well-tested runners, or 87 to 92% of threshold HR if you know it. The catch: max-HR formulas lie for at least half the runners I test. Use HR to confirm the talk test agrees, not to set the pace.

If two of the three agree, you have your tempo pace. If they disagree, trust the honest race first, the talk test second, and the watch last.

How long to hold tempo, by race distance

The length of the tempo should track the race you are training for. A 15-minute tempo is a warm-up for a marathoner and a full session for a 5K runner. Rough ranges I coach to:

Warm up before every tempo with 15 to 20 minutes of easy running plus 4 strides. Cool down after with at least 10 minutes easy. A tempo cold is a hamstring on borrowed time.

How often to run tempos in a training block

Once a week during the build phase. Every 10 to 14 days during peak, when race-specific interval work takes priority. Never during taper week, and never twice in the 72 hours before a race.

The pattern I watch for: runners read one article, run a tempo on Tuesday, feel it open something up, and try to run one every three days. By week four every session feels flat. Nothing is broken. The block just needed rest between tempos.

Three tempo workouts I give my athletes

Every runner I coach cycles through these three formats over a full block. Same physiology, different rhythms, and each teaches something the others do not.

1. The continuous tempo

A single sustained block at threshold. This is the classic tempo, and the best format for building the pure ability to hold pace when it wants to fall apart.

• Warm-up: 20 min easy plus 4 x 20-sec strides
• Tempo: 25 to 40 min continuous at threshold pace, depending on race distance
• Cool-down: 10 to 15 min easy

The last 5 minutes should feel like you could hold it for another 5, not another 20 and not another 1. If you finish and think "I could have gone another 15," you were 10 seconds per mile too slow. If you cannot cool down and talk, you were 10 seconds too fast.

2. Cruise intervals

Threshold effort broken into 8 to 15 minute reps with 60 to 90 seconds of easy jogging between. Same total time at pace as a continuous tempo, easier on the head, and slightly higher weekly tolerance.

• Warm-up: 20 min easy plus 4 strides
• Work: 3 x 10 min at threshold pace with 90 sec jog rest, or 4 x 8 min with 60 sec rest
• Cool-down: 10 to 15 min easy

Cruise intervals are my go-to when a runner is either building volume at threshold for the first time or coming back from a break. The short rest keeps the aerobic effect. The gap keeps the head fresh.

3. The progression tempo

Not tempo throughout. It starts at moderate pace, drops into threshold in the middle third, and finishes at threshold or slightly under. This one trains the same system as the classic tempo and also rehearses the exact demand of a well-paced race, where the effort climbs over time even when the pace is steady.

• Warm-up: 15 min easy
• Work: 3 mi at marathon pace, then 3 mi at threshold, then 1 mi at threshold or 5 sec/mi faster
• Cool-down: 10 min easy

Use this format in the last four weeks before a half or full marathon. Skip it for 5K training. It is a specificity session, not a base session.

Three patterns to watch for

The mistakes I see most often on self-coached tempos, in the order they cost runners the most fitness.

Running the tempo too fast

The most common one, and the one that quietly wastes the block. A tempo done at 5K to 10K effort is not a tempo. It is a hard interval session in disguise. The aerobic adaptation you are chasing needs sustained sub-threshold work, not repeated maximum aerobic hits. Every 10 seconds per mile faster than true threshold costs you a chunk of the intended stimulus and doubles the recovery bill.

The fix is boring. Take the first mile 5 seconds slower than you think you can. If it feels easy, hold it anyway. If mile 2 still feels controlled, only then let it drift toward true threshold. You should finish thinking "that was hard, but I could keep the wheels on."

Making the tempo too short

If your tempo work is under 15 minutes at pace, you are running a warm-up. Threshold adaptation is time-under-tension work. The first 8 to 10 minutes are your body arriving at the intended physiological state. The training effect happens after that.

Runners cutting tempos short is usually a schedule problem, not a fitness problem. If your Wednesday is compressed, move the tempo to Thursday rather than shorten it. An honest 25-minute tempo teaches more than three cropped 8-minute ones.

Running in the gray zone every day

Not a tempo mistake exactly. A pattern the tempo often gets absorbed into. If your easy days are moderate, your long runs are moderate, and your tempos are moderate, everything happens in a narrow band around threshold. The aerobic base never gets built and true threshold never gets stressed hard enough to move. Every runner I have coached out of this rut needed the same medicine: easy days a full 90 seconds per mile slower than they thought, and tempos a real 15 to 20 seconds per mile faster. The post on why most easy runs are too fast covers the easy side of that same problem.

What to do on your next tempo

If you are running one this week, five steps that make the session count:

1. Pick a target pace using an honest recent race or the talk test. Do not use "how you feel today."
2. Warm up for 20 minutes plus 4 strides. Non-negotiable.
3. Run the first mile 5 seconds slower than target. Let pace settle in.
4. Hold the middle in a way that lets you speak four-word sentences and no more.
5. Cool down for at least 10 minutes easy. Log how it felt, not just the split.

If you want your tempos built into a real week, alongside the easy runs, the long run, and the strength work that makes it all repeatable, that is what the two coaching tiers are for. And if you want that plan calibrated to your fitness week by week rather than pulled off a template, the week-to-week coaching relationship is how it stays honest. About 16 of 20 roster spots are usually filled. Apply and I will read it personally.

Written by

Coach Johnny Crain

2:12 marathoner. 4× US Olympic Marathon Trials qualifier. 4× NCAA national champion and 4× NCAA runner-up. Spoke at the RRCA National Convention. Founder and head coach at RunFitCoach, where he coaches every athlete personally.