The How and Why of a Tempo Run

Whether you run the 5K or the marathon, you will benefit from this tried-and-true running workout: the tempo run. There are no magic workouts in training. No single workout will achieve all of your running goals. But, as part of a well-rounded training plan, the tempo run is an effective workout for distance runners.

Tempo runs prolonged efforts at a moderate to moderately hard intensity. That intensity will vary based on the duration. Sometimes, a tempo run is run near lactate threshold; other times, it is closer to marathon pace.

The Physiology of Tempo Runs

Tempo runs are paced at a moderate intensity, typically between your aerobic threshold (sometimes called first ventilatory or first lactate threshold) and your lactate threshold. These workouts improve your body’s ability to shuttle lactate back to the cells, as outlined in this 2023 review in the International Journal of Environmental Research and Public Health. This shuttle delays lactate accumulation in the blood, which in turn delays muscular fatigue due to hydrogen ion accumulation. The lactate shuttle also allows your body to oxidize lactate into glucose for energy. Over time, more efficient lactate shuttling leads to a glycogen-sparing effect – which helps you run at a faster pace for longer without fatigue. While you need zone 2 training to develop mitochondria for this process, tempo runs train this process to happen at faster velocities.

Beyond the lactate shuttle mechanism, tempo runs confer additional benefits. As a result of moderate-intensity workouts, various chronic adaptations occur to the heart. Stroke volume increases, resulting in greater cardiac output (more oxygen-rich blood sent to working muscles). AMPK-signaling occurs, which leads to mitochondrial proliferation.

Using a Tempo Run in Training

Shorter tempos of 15-30 minutes are often at hour-race pace (lactate threshold), while longer variations can be at half marathon or even marathon pace. When you do these workouts enough, you improve your ability to sustain a faster pace for longer before fatiguing.

Beyond basic physiology, tempo runs train valuable skills for runners. They teach you how to control your pace over an extended period of time. If you constantly start out too fast in workouts or races, these workouts train you how to appropriately pace over a longer period of time. You also learn how to become mentally comfortable with prolonged physical discomfort and how to resist fatigue at the end of a run. If you are racing a half marathon or marathon, these skills are vital for a successful and enjoyable race.

According to a 2021 study published in the Journal of Strength and Conditioning Research, tempo runs are a high predictor of long-term success for long-distance runners. If they are not already part of your training, you may want to start introducing one every couple weeks. Since they are demanding workouts, most runners will want to do only one per week.

Tempo Run Workouts

Think of the paces of tempo runs as the spectrum, based on the format of the workout. Indeed, it’s not that hour-race pace is magically effective and slightly slower or faster is ineffective. If you are working within the moderate-intensity zone, it is an effective workout. One big caveat: these are workouts, not time trials. Faster is not better – you should finish with a little bit in the tank.

• Threshold tempo: Most runners think of threshold effort when they think of tempos. These last 15-30 minutes (sometimes divided with short rest, such as 2 x 10 min or 3 x 10 min) and are paced at one hour-race effort.
• Half marathon pace tempo: For some runners, these may be only slight slower than threshold pace. Half marathon pace tempo runs are most effective in the six to eight weeks before a goal half marathon race. Depending on your pace, these likely last 30-45 minutes.
• Marathon pace tempo: These are longer, slower tempos done at marathon pace – a truly moderate effort. Marathon pace tempos will be slightly longer, up to 60-90 minutes in duration. Longer marathon pace tempos are used in marathon training, while shorter ones can be used to support ultra marathon distances or early-season half marathon training.

Tempo runs can be a standalone workout or structured as part of a long run. Long run workouts are more demanding, so these variations of the tempo run are best reserved for experienced runners.

Pacing a Tempo Run

Your body provides the best feedback for pacing. You can use recent race times to estimate your tempo paces, although these paces will be affected by weather and terrain. 

The effort should feel moderate to moderately hard in relation to the duration of the run. Your breathing will be more labored, but you should not be gasping for air. A 2-count inhale, 2-count exhale pattern is generally appropriate. If you can speak in short phrases (such as “pace feels good”) for the duration of the workout, you are working at the appropriate effort. In terms of perceived exertion, a tempo run should feel like a 6-7 out of 10. 

As with many workouts, you should not exhaust yourself during a tempo run. If your breathing is so labored you can barely speak, scale back. Unless you haven’t raced in a long time, you should not try to be setting PRs in a workout. Read this article for more practical information on how to do a tempo run.

When to Do Tempo Runs

The beauty of a tempo run is that you can incorporate it into various points of your training plan. For 5K runners, it serves as a foundational workout several weeks out from their race. A 5K plan will likely include some short tempos around lactate threshold (slower than 5K pace). A 10K training plan may include tempo runs at lactate threshold.

Once you get into the half marathon and marathon, tempo runs may be structured differently. Half marathon training plans will include shorter tempos early in the plan and then longer tempo runs at goal pace later in the pan. Marathons can use slower, high-volume marathon tempos to practice race pace (such as one of these effective marathon workouts). Both plans may also include tempo runs or tempo intervals at lactate threshold.

How to Progress a Tempo Run

Progressive overload is the principle that as you adapt to training, the workouts must become gradually more difficult to continue to produce results. The principle of progressive overload applies to tempo runs, so long as the workout stays true to its purpose.

For example, if you start with a 20-minute tempo run at threshold effort, you will likely progress it as your race approaches. A 10K runner may progress to a 35-min tempo run at threshold effort. A half marathon runner may progress to a 45-min tempo run at goal race pace or mile repeats at threshold effort.

At a certain point, tempo runs do not become longer or faster. Generally speaking, a tempo run at lactate threshold will not exceed 40 minutes, even for the fittest individuals. If you are doing a 60-minute tempo run at one-hour race pace, you are not doing a workout – you are race. Half marathon pace tempo runs are generally capped at 45-60 min for very experienced runners. Marathon tempos are usually capped at 1.5 hours. Too long of a tempo run may increase injury risk, as you experience biomechanical breakdown after a prolonged period at a moderately hard intensity.

Likewise, a tempo run pace won’t progress faster than one-hour race effort. At paces faster than lactate threshold, physiology becomes too unstable to maintain for prolonged efforts without excessive fatigue. This is why critical velocity workouts (30-40 min race effort) are broken into intervals.