Tempo running is also known as Fast Continuous Running, lactate-threshold or anaerobic threshold training. And as the glut of names suggest, it’s a popular form of training. Alas, the plethora of different threshold concepts has led to quite a bit of confusion.1 So the time has come to demystify this hitherto nebulous training concept.
Somewhere between easy and all-out, lies tempo training. Tempo runs are a longish, fastish workout, at constant pace. It’s a middle ground workout, straddled between long, slow training and short, intense exercise. Clear as mud? It gets clearer. Promise.
What is a Tempo Run?
A bit of background first. Tempo training is all about lactate. When you exercise your muscles produce a substance called lactate. Lactate build-up is associated with (but not the cause of) fatigue, less powerful muscle contractions, and the strong desire to slow down and rest.2
The faster you go, the more lactate your muscles produce. During very low-intensity exercise you’re producing and clearing lactate at an equal rate. But increase the intensity to an RPE of about 9 or 10, and you hit a point called the 1st lactate threshold (also called the aerobic threshold). At this point you start producing lactate a little faster than you can clear away, causing lactate levels to rise slightly. Exercise at the aerobic threshold can be sustained for hours. Long slow distance training is done around this turn point.3
Now increase your pace again, to an RPE of around 14, and you’re suddenly generating lactate much faster than you can neutralize, causing lactate to rise exponentially in your bloodstream.4 This point – the point at which there is an abrupt increase in lactate – is known as the 2nd lactate threshold (the pace at this point is known as lactate threshold pace) and is the one in which we’re interested.
The 2nd lactate threshold marks the change from moderate-intensity to high-intensity exercise. Tempo runs center on exercising at or near this lactate threshold.56 It is an intensity that can be maintained no more than 45–60 minutes.7
This lactate threshold also marks the transition from predominantly aerobic to mostly anaerobic exercise. In other words, at lactate threshold pace (i.e. tempo pace) you’re running at the fastest pace you can, while still working aerobically, albeit, only just!
Tempo runs are a type of threshold training. You’re exercising at the “red line” of training intensity; crossing it and going faster results in fatigue, while exercising less intensely doesn’t stress the muscle and cardiovascular system as effectively.8
There’s quite a bit of confusion and inconsistency of the terminology around lactate threshold. The 2nd lactate threshold is also known as the anaerobic threshold, onset of blood lactate accumulation (OBLA), and maximal lactate steady state (MLSS), to name a few. For simplicity’s sake, from hereon in, we’ll refer to it just as lactate threshold.
Why do it?
The Benefits Tempo Runs
So what’s so special about tempo training? Simply put, lactate threshold is a great predictor of distance-running performance.9 If you’re unfit the point at which you hit your lactate threshold is pretty pathetic (okay – let’s call it low). The more fit you are, the higher your lactate threshold.1011 And tempo runs do just that. It makes your body better at clearing lactic acid and raises the lactate threshold.12
In other words, tempo training delays the point at which lactate levels start to rise, thereby postponing the point at which you feel fatigue. This translates into greater stamina and speed.
While there is quite a lot of debate on the perfect way to train and the effectiveness of tempo workouts,1314 research suggests tempo training can induce favorable adaptations in mitochondria (the tiny power plants of the cell), improving the ability to generate energy and reducing the formation of lactate. Tempo runs also stimulate the development of blood capillaries around the muscles, boosting blood flow, which improves the clearance of lactate from working muscles and oxygen delivery to them. 15161718
What does this mean? The body can clear lactate more quickly and deliver more oxygen to your muscles. You can get your heart rate up and keep it there. In short, you can run faster and longer with easier effort.
- Tempo workouts put you more in tune with your abilities, as well as limits, and help you understand how different paces feel.
- It is mentally challenging and simulates the toughness called for during a race. Tempo runs train you to dig deeper, increasing mental strength and focus.
- Teaches you to run steady and hard, but not too hard, mimicking race conditions without the physical stress thereof.
Who should do it? If you want to improve fitness or performance at any race distance, especially for longer events such as 15K and upwards.
How often? Perform a tempo workout every 1 – 2 weeks. Do no more than one tempo run per week. Tempo workouts (specifically exercising at lactate threshold pace) should constitute a maximum of 10% of the total volume (time or distance) of your weekly training, in order to reap maximum results, avoid overtraining and reduce the risk of injury.212223
A good tempo run is as much about pushing your mind and resolve as it is your muscles, heart and lungs. The demanding nature of this type of workout means you should be well rested before each tempo workout and allow for adequate recovery afterwards.
How to Find Your Tempo Pace
The key to proper tempo runs is to exercise at the correct pace. Tempo training is all about balancing on a performance edge. So, the goal is to find it and hold it there. However, the trickiest thing about tempo workouts is to find your tempo pace – your lactate threshold pace. It takes a little practice and mindfulness.
The most accurate means of finding your lactate threshold pace is in an exercise physiology lab. The more realistic, low-tech way is to use a variety of practical methods to determine your lactate threshold pace.
Knowing what the right pace feels like is an important means of gauging effort level and a good indicator of lactate threshold.24 For a tempo workout you should run at a pace coaches that is “comfortably hard”, which you can maintain for up to an hour.25 This is about a 13 – 14 on the original RPE scale (about 6 – 7 on the modified RPE scale).26
A workout that is both comfortable and hard seems gobbledygook, an oxmoronic nonsense. But, what it basically means is that you are running sufficiently fast to feel you are working hard (and look forward to the end); nevertheless if you had to, you could keep going for up to an hour. If you are unable to maintain the pace you’re running too fast, while if have too much energy at the end of your workout the pace was too slow.
- Talk test: You are only able to say a few words at a time.
- Breathing: Breathing is fast but still under control. You can hear yourself breathing, but you’re not gasping for air.
Runners tend to breathe in a very rhythmic way. This rhythm matches the runners stride rate, each time taking a specific number of steps when they breath in and when they breath out. When runners hit their lactate threshold pace, their breathing rhythm changes.
During easier workouts many runners breathe in a 3-3 breathing pattern. This means they inhale while taking 3 steps and exhale during 3 steps. At lactate threshold pace, breathing rhythm for most runners switches to a 2-2 pattern of breathing (inhale for 2 steps and exhale for 2 steps).27
The heart rate at lactate threshold (i.e. tempo pace) varies greatly from person to person – depending on fitness level and genetics. For example, lactate threshold occurs at approximate 90% of maximum heart rate in seasoned runners, but can be at around 70% of maximum heart rate in beginner runners.282930
Therefore, for heart rate to be effective you need to personalize it and determine your heart rate at your lactate threshold.
Lactate Threshold Test
30-Minute Time Trial
Do not partner up with a running buddy or complete this time trial as part of a race, since this increases motivation and changes the outcome. You will need a heart rate monitor and a stopwatch.
- After a warm-up, complete a 30 minute run at race pace.
- Ignore your heart rate in the first 10 minutes, as your heart rate is still increasing toward the lactate-threshold.
- The average heart rate from the final 20 minutes is the estimated heart rate at lactate threshold (i.e. tempo run pace).
If you don’t have a heart rate monitor, take your heart rate at the 10-minute and 30-minute mark. Add these numbers together and divide by 2. This number is your lactate threshold heart rate.
Lactate threshold is closely associated with race pace. This holistic approach, pegs your lactate-threshold pace to your actual performance, including information from your whole body – heart, leg muscles, and all.
The right pace will depend on your level of fitness:33
- Beginner and intermediate runners. 15-30 seconds per mile slower than 10K race pace; or 30-45 seconds slower than 5K pace.
- Advanced runners. 10-20 seconds per mile slower than 10K pace; or 25-35 seconds slower than 5K pace.
Finding the right tempo takes practice. A tempo run is all about control, balancing on a performance edge. When you run too fast (a common error), you don’t reap any extra benefits and you risk overloading the body. On the other hand, running too slow results in failing to make the physiological gains you wanted. It will take a few tempo runs before you get a “feel” of the pace and it becomes ingrained, so that you can find your training zone and regulate your running pace intuitively and effectively.
Ideally perform your tempo runs in mild weather conditions on flat terrain. Tempo pace can vary depending on the weather (wind, temperature, humidity), the terrain, how you feel (stress, fatigue), and improving fitness. Using perceived effort (how it feels) to gauge your effort helps you to run steadily at the right effort level, because you are self-regulating for every variable on the day.
Types of Tempo Runs
There are a myriad of tempo workouts. Some are more “comfortably hard” than others, some longer than others and some shorter. What they all have in common is that they revolve around lactate threshold pace, and may be slightly above or below it.
There are three broad categories of tempo workouts.
Continuous Tempo Run
The classic tempo workout consists of running continuously at lactate threshold pace for 20 minutes (3-4 miles). It’s the original and still the gold standard for many people.
How to do it: Run for 20 mins at your lactate threshold pace. Warm-up and cool-down with 10-15 mins of easy running.
Runners new to tempo workouts should start with 10-15 minutes. Gradually extend the length of the workout as your fitness increases.
The are many twists on the classic (steady-state) tempo run. Below are just a few of those variations:
- Long tempo run. A workout longer than 20 minutes (tempo workouts 20-40 minutes in duration are quite popular). However, there is some debate as to the effectiveness of long tempo workouts. Some experts prefer breaking up a longer bout of running into shorter sections, interspersed with periods of recovery. In other words, tempo intervals that are no more than 20 minutes long.34
- Fast tempo run. Simply a variation of the traditional tempo run, but at a slightly higher intensity. This is for more experienced runners. The pace is approximately 10 seconds per mile slower than 10K pace, for 20 – 30 minutes. Best for occasional training for a 5K or 10K.
- Marathon tempo run. Slightly slower and longer that your classic tempo run. Workouts are at or between half-marathon and marathon pace. Primarily training for marathoners and half-marathoners.
What is it? Tempo intervals (also known as cruise intervals) are basically broken up tempo runs. Intervals are performed at around lactate threshold pace and followed by short recoveries (slow jog). The short recovery periods reduce psychological difficulty and allow lactate levels to fall, but not too much.
This method of tempo training allows runners to train longer at threshold pace, can help prevent that common error of running too fast, and reduce the risk of injury:
- Beginner and intermediate runners. Often don’t yet have a good sense of tempo pace, the discipline to hold that pace, the physical fitness, or the mental endurance to correctly complete a continuous 20 minute tempo run. Breaking the tempo workout into intervals solves that. It gives the body a rest, allows you to reassess your pace, and is less mentally taxing.
- More advanced runners. Adds variety to workouts and the break makes it less challenging, allowing you to train longer at lactate threshold pace. However it does make the tempo workout feel less like a race effort, which means you sacrifice some of the unique benefits of classic tempo training.
How to do it: Complete 2 x 10-min intervals at lactate threshold pace, each followed by a 1 – 2 minute recovery period. This splits a tempo run in two and allows you to maintain a quality run throughout. Split it into 4x 5 minute intervals to make it easier. Complete a 10-15 minute warm-up and cool-down.
Tempo intervals should be at lactate threshold pace (shorter intervals might be run a smidge faster). If the intervals feel too easy, increase the length of the tempo interval or shorten the recovery time. Some experts like to limit the length of recovery intervals to about 20% the length of the previous interval.35
What is it? A workout that starts off easy and gradually increases in speed to lactate threshold pace (or a notch faster). In other words, it gets progressively harder.
Progression workouts are about challenging both mind and body. It teaches control and discipline, training you to be mindful of your pace. Progression runs also train you to run with increasingly fatigued legs.
How to do it: Start a 30 minute run at conversational pace (about a minute per mile slower than current 10km pace), then gradually increase the pace (by 10-15 seconds per mile) every 5 minutes until you are running at about lactate threshold pace last five minutes. Warm up and cool down for 10- 15 minutes.
Tempo runs are a great way to increase running performance. This intuitive, comfortably uncomfortable workout takes patience, mindfulness, and time to master. There is great variety in tempo training, but the one thing to remember is to run steady at your tempo pace.
- ACA (American Council on Exercise). How to Design a Lactate Threshold Training Program. Available from: acefitness.org/education-and-resources/professional/prosource/february-2015/5243/how-to-design-a-lactate-threshold-training-program/
- CDC (Center for Disease Control and Prevention). Physiologic Responses and Long-Term Adaptations to Exercise. Available from: cdc.gov/nccdphp/sgr/chap3.htm