Tempo Hill Intervals
Tempo hill intervals are a variation of short hill intervals that get around the problem of the long recoveries associated with normal hill training.
During tempo hills the aim is to maintain a greater average intensity by running the uphills at above threshold intensity whilst maintaining a steady intensity on the downhill. This makes tempo hills intense and challenging – both physically and mentally – but highly beneficial to distance running performance.
You get all the same benefits associated with other short hill intervals: improved muscular strength, running efficiency, muscular endurance, improved aerobic and anaerobic metabolism. However, tempo hills place much greater emphasis on muscular endurance, fatigue resistance, and push the upper limits of aerobic metabolism. If that wasn’t enough there is a strong anaerobic component. And as an added bonus you’ll give your lactate threshold a serious workout as well.
In short this highly effective hill session should lead to greater improvements in lactate threshold, aerobic and anaerobic endurance and endurance running performance.
Whilst this session might seem like it’s less effective for improving muscular strength and anaerobic power. You might be surprised to see just how effective this session can be at training anaerobic as well as aerobic metabolism. Later in this article I’ll share with you some running power data from a recent tempo hill session, that will show you just how effective these hills can be. And may be encourage you to give these hills a try for yourself.
What are tempo hills?
The basic idea of tempo hill intervals is to run the uphills at above threshold intensity, whilst running the downhills at just below threshold intensity. So here we are controlling the intensity of the downhill recovery as well as the uphill effort. By doing this we maintain a higher average work rate throughout the workout.
This works well with short hills (~20-60seconds duration) that are moderately steep (~4-6% gradient). The real difference between tempo hills and standard hill intervals, is that the recoveries should only take around 15-25% longer than the uphill section. Often with short hills the recovery time can be more than twice the length of the effort. So we are significantly reducing the recovery time.
Typically this would equate to ~5-8secs slower on downhill, for a 30second hill rep. So that would be 30seconds uphill and around 35-38seconds for the downhill section.
This is significantly less than with other hill intervals where the recoveries may be several times longer than effort. The idea is that you are getting the minimum recovery period needed in order for you to maintain a good (above lactate threshold) pace on the up hills.
Whilst this recovery sounds quite challenging, you do have the the assistance of gravity on the downhill. Here the gradient can have a significant impact – the steeper the gradient the easier it is to run a fast descent.
How do tempo hills differ from Kenyan hills?
The main difference here is that with tempo hills there is a greater difference in intensity, between the uphill effort and the downhill recovery. Kenyan hills are more about maintaining a steady pace on both the uphill and downhill section.
With tempo hills we push the uphill section like you would during track based intervals. Then on the recovery we reduce the intensity just enough to allow us recover so we can maintain the work rate on the uphills. In this sense tempo hills are more like an interval session.
As you get used to running these, you will find that you can start to increase the intensity of uphills. In fact, with consistent training it’s possible to push the uphills at close to VO2max intensity, whilst running the downhills at just below threshold intensity. This allows you to maintain an average intensity that is very close to threshold intensity.
How to run tempo hills
As always, start with a good warm up including mobility exercises, dynamic stretching, strides, accelerations and ideally some drills. Once fully warmed up you’re ready to start. All you need now is a hill with a moderate gradient (ideally 4-6%) and the willingness to push through the inevitable build up of fatigue.
For the tempo hills run the hills continuously as either one continuous tempo hill session (e.g. 20-30minutes), or broken into smaller interval blocks e.g. 2-3 x 10minutes of tempo hills, separated by 3-5mins of easy running. Alternatively you can run a set number of hill intervals rather than running by time. As an example sometimes I may run these as 3 sets of 10 x 30sec tempo hills.
The intensity of the uphill should vary depending on the training focus, length of the hill, training experience and your current run fitness. For longer hill tempos (50-60seconds duration – I wouldn’t go longer than this) the intensity for the uphill section should be in the region of 5/10k intensity (as a minimum). With shorter hills this intensity can be increased. The key is to find an intensity that can be sustained across all the hills.
When I run these prefer to use shorter hills (~30-35secs). Using slightly shorter hills allow you to maintain a higher overall intensity on the uphills. This also means the length of the recovery is shorter (35-40secs compared with 60-65secs for a longer 55-60sec hill) which helps to maintain a high overall intensity. This also means there is a less significant drop in heart rate during the recovery.
Typically I run these sessions so that the uphill intensity is around 1500m/3km intensity, whilst the downhill is run at an intensity that is slightly below marathon intensity. However, since analysing the data from these sessions it’s clear that the true intensity is actually higher than this. Making these sessions far more effective than you would expect.
How to control the intensity of tempo hills?
Controlling the intensity of the tempo hill intervals and recoveries is key to getting the most out of these sessions. As with any short repeated efforts this can be challenging. So what’s the best way to control the intensity? Here, we have a number of ways to control/monitor the intensity: heart rate, pace, time, running power, perceived effort. Each have their own benefits and limitations.
How I control the intensity during tempo hills?
Personally I focus most attention on perceived effort. But I still take into account heart rate, running power using the Stryd footpod. I also check lap times for the uphill and downhill sections to maintain consistency.
We should always consider heart rate as this gives a measure of the actual physiological stress you are experiencing during the workout. It also accounts for daily variations in fitness and fatigue. And can be an early warning if something is not quite right.
As mentioned pushing the intensity too much over the first half of these sessions can negatively impact intensity over the second half of the session. Here it helps to deliberately go a bit easier over the first few intervals. The image below shows how starting at a lower intensity over the first few intervals can allow you to maintain a more consistent effort (see running power) over the rest of the workout. You can also see the effects of cardiac drift and how heart rate continues to rise throughout the tempo hills session even though power is consistent.
Why are tempo hills so effective?
Tempo hills are highly effective for improving running fitness and performance. But why are they so effective? In short this is because they combine the benefits of interval training with an average intensity that’s very close to threshold intensity. During the session you run continuous hills switching between running above threshold intensity on the uphills and just below threshold intensity on the downhill. In fact as it turns out the uphills can be run at an intensity that’s significantly above threshold.
Tempo hills and Lactate Threshold
Tempo hills are run at an average intensity that is very close to the lactate threshold. Making this a great session for lactate threshold training.
In the image below you can see power data from a recent tempo hill session, consisting of just over 25minutes of continuous hills. On the image I’ve highlighted threshold intensity – in terms of running power – so you can see how running power changes during the uphill intervals and downhill recoveries.
Here you can see how running power alternates between short periods above threshold (uphill efforts), with short periods below threshold (downhills).
The average power for the 25mins of tempo hills was 334w – just 4w (~1%) below threshold power. In fact during the hill tempos, 64% of the total training time was spent at a running power that was at or above the threshold training zone – only 36% of training time was below threshold intensity.
Because the spikes in power are quite significant (we’ll look at this shortly) you are getting more than just the benefits of training at threshold intensity. You’re also working significantly above threshold for large parts of the workout.
Tempo hills and aerobic capacity training
Running at threshold intensity is great on its own for developing aerobic fitness.
However, by pushing the uphills above threshold intensity you get the added benefit of really working maximal aerobic capacity.
The data from my tempo hill sessions shows that 41% of total training time was spent at a power equivalent to or above the VO2max training intensity zone. The interesting thing here is that if we were just looking at the average power for the intervals we would think the intervals weren’t this intense. In fact the average power for the uphill intervals was below VO2max power. However, there were significant periods where power was above VO2max intensity.
So why does average power not reflect the true intensity of the intervals? The reason here is mainly due to the lower power at the start of each interval (acceleration phase). Here the power was around 40% lower over the first 5 seconds of every interval. This pulls the average intensity down significantly. But it also tell us that the average power for the remainder of the interval must be significantly higher.
Clearly it’s important to look beyond averages, when analysing data.
So as if training at an average intensity equivalent to lactate threshold wasn’t enough. And also spending 64% of total training time at or above threshold training intensity. Approximately 41% of the total training time (or ~10.5minutes) was spent at an intensity equivalent to or above maximal aerobic running power!
So as well as training the lactate threshold we’re also training aerobic capacity by working at or above VO2max intensity.
And if that wasn’t enough….
Tempo hills and anaerobic endurance and conditioning
The most surprising part when I looked at the power data was just how effective these hills were for hitting the anaerobic training zone.
A surprising 22% (~5.5minutes) of the total training time was spent at a power that was in the anaerobic training zone. Here we are viewing the anaerobic training zone as being where running power is more that 115% of threshold power.
So not only are these hills great for lactate threshold development and maximal aerobic capacity (VO2max), they are also great for training anaerobic endurance and anaerobic conditioning.
Often there is a concern that reducing the recovery length can have a negative effect on training by reducing the intensity. Whilst the shorter recoveries mean you won’t hit the same intensities that you would achieve with a longer recovery period. These hills give us the combined benefits of working the lactate threshold, aerobic capacity and anaerobic endurance and conditioning.
They also provide a benefit for both cadence and stride length.
Running Cadence and stride length
Tempo hills are great for working both cadence and stride length.
Whilst both the cadence and force per foot strike is slightly less compared with short hills with longer recoveries. Significant amounts of this workout are spent with a running cadence and power that are greater than the equivalent at VO2max intensity. As this is combined with a strong endurance component – repeated efforts with short recoveries – we’re training our ability to maintain both a fast cadence and good force per foot strike.
We know that significant parts of the workout were run at an intensity above VO2max power which is beneficial for stride length. As well as this the average cadence was 193spm during the uphills. This is very close to my cadence at VO2max intensity. Whilst the average cadence during the uphill was 193spm, this was higher during the first 15-20secs of each hill rep. Here average cadence was just above the cadence at VO2max. So during these sessions the greatest training effect on cadence comes during the first part of each interval. Whereas stride length is trained more effectively over the second half of the interval – where power per foot strike is greater.
Example tempo hill sessions:
Hopefully by this point you’re looking to give these sessions a try.
A word of caution first, these hills can be very intense and fatiguing. It’s important that you are physically prepared, have completed a significant amount of base training and general conditioning (including preparatory hill training such as longer hills) before attempting tempo hills. When you first use these, start at a lower intensity and don’t push the uphills too intensely. After a couple of sessions you will start to find these easier and will be able to increase the intensity of the uphills and maintain a higher intensity on the downhills.
Also look to start by splitting the session into smaller more intervals and progress to running these as one continuous tempo hill session.
Basic tempo hills (TH):
- 4 x 5 mins TH, 2-3mins recovery between sets
- 4 x 6 mins TH, 2-3mins recovery between sets
- 3 x 8mins TH, 3-4 mins recovery between sets
- 2 x 12mins TH, 3-5 mins recovery between sets
- 3 x 10mins TH, 3-5mins recovery between sets
- 1 x 25-30mins TH
Advanced tempo hill variations:
- 10min Tempo Run + 3-5mins easy + 10mins TH + 3-5mins easy + 10min Tempo Run
- 10mins TH + 3-5mins easy + 10min Threshold/Tempo + 3-5mins easy + 10min TH
- 10mins TH + 3-5mins easy + 10min Threshold/Tempo + 3-5mins easy + 10min TH + 3-5mins easy + 10min Threshold/Tempo
- 20mins TH + 20min Tempo
- 10min TH + 4-5mins easy + 6 x (30 sec Hills – hard effort, 2-3min recoveries) + 4-5mins easy + 10min TH
How often to include tempo hills?
Tempo hills have that unique combination of a high average intensity combined with a strong aerobic and anaerobic component. On top of this there is increased muscle fibre recruitment which places greater stress on the nervous system. Taken together this makes these intervals very effective for training but also very fatiguing. Because of this we have to be cautious with when and how often we use these sessions. Especially if we really push the intensity.
From my own experience, 2-3 of these sessions during a 8-12 week training block can be highly effective.
When to incorporate these?
I find the training adaptation from these hills is fairly quick – typically just 2-3 weeks (sometimes quicker). Due to the intensity of these sessions we don’t want to do these too close to key races.
Typically including 2 of these sessions 3-6weeks before a key race can be beneficial. As always this is not the same for everyone. You can see examples of how to incorporate these on the following 10k training plans:
How hard should you push the hills?
This depends a lot on your current run fitness, ability to recover between intervals and ability to push through the fatigue as that inevitably sets in. Typically I push the uphills at between 1500m and 3k intensity. However, when I first reintroduce these to a training block the intensity will be lower (~3k/5k intensity). If you haven’t done these before start at a lower intensity and see how that goes. Then look to increase the intensity over subsequent sessions.
When it comes to getting the most out of the session. Always run the first few at a slightly easier intensity. Gradually increasing each one until you feel like you’ve reached an intensity that you can sustain across all of the remaining intervals. You can see an example of this in the earlier image showing “running power and heart rate during tempo hills”.
What about the intensity of recoveries?
I like to think of the recoveries as a steady intensity – just below marathon intensity. It should feel like you’ve eased off the gas slightly, but are still running at a decent “steady” down hill pace with the assistance of gravity.
Tempo Hills Summary:
- Tempo hill intervals are a variation of short hill intervals where you alternate between a high intensity uphill and a steady pace recovery on the downhill.
- These differ from Kenyan hills in that the intensity is slightly higher on the uphill and slightly easier on the downhill. In this way they are more like an interval session.
- As with other running hill training sessions tempo hill intervals can lead to improved muscular strength/endurance, running economy, and both aerobic and anaerobic metabolism.
- The average intensity of the workout is close to lactate threshold intensity. As such this can lead to improvements in the lactate threshold.
- These are surprisingly effective for developing aerobic and anaerobic endurance.
- Tempo hills are also beneficial for training running cadence and stride length.
- The intensity of the hills is best controlled by a combination of perceived effort, heart rate, running power and monitoring lap times.
- Tempo hills can be run as one continuous session (20-30minutes of hills) or split into smaller work intervals (3 x 8-10mins). They can also be combined with tempo running for a more advanced workout.
- Tempo hills are very intense and should not be used too often in a training cycle. Or too close to key races.