Long Hill Running Intervals
Long hill intervals are a highly specific type of strength endurance running training. Typically these involve running intervals up a moderate (3-5%) gradient for between 90secs and 5minutes. These can be extended up to around 10minutes, if you’re looking to run at lactate threshold intensity.
These intervals are similar in duration and intensity to intervals commonly used by distance runners when completing track running intervals such as 600, 800 or 1000m intervals. The difference here is that we’re running up an incline to give us the added benefit of working against gravity. By doing this we increase the amount of force per foot strike, making these hills a great way to improve muscular strength and endurance.
Normally these are run at an intensity that is close to, or slightly below maximal aerobic capacity (VO2max). An example session would be 5 x 3mins long hills at VO2max intensity, with a 3minute jog downhill as the recovery.
Unlike short hill intervals these place a much greater emphasis on aerobic endurance than anaerobic endurance. These also place a much greater emphasis on muscular endurance and strength rather than power.
The Benefits of Long Hill Intervals
As with other types of hill training, long hill interval training can improve muscular strength, running economy, muscular endurance, fatigue resistance, and aerobic metabolism. There is a much reduced emphasis on anaerobic metabolism, due to the reduced intensity compared with short hill intervals. Therefore, this type of hill training is more suited to long distance runners than middle distance runners. However, these can be useful for all runners, especially during the preparatory phases of training.
Although these sessions place a greater emphasis on aerobic metabolism, the recovery periods are long due to having run back down the hill for the recovery. As an example the recovery period for a 3 minute long hill interval would typically take around 4 minutes to run the recovery back to the start of the hill.
Due to this I tend to run these more like a classic VO2max session by running 3 minute up hill intervals at close to VO2max intensity (normally I run these at around 3km intensity). These are then followed by just over 3minutes of downhill running. In this way these are very similar to the classic VO2max session of 5 x 3mins at VO2max pace, 3minutes at half VO2max pace. The difference here is that we need to use intensity rather than pace to control these intervals, due to the way incline affects pace. For this I use running power as a measure of running intensity.
Long hill intervals vs intervals on flat terrain
So why run these VO2max intervals on a hill rather than on flat terrain? The main difference here is that whilst the intensity might be similar to running on flat terrain, more force is generated per foot strike when running uphill. This makes these beneficial for strength development and muscular endurance as well as maximal aerobic capacity.
So why does power per foot strike increase with long hills? The increase in power per foot strike relates to a slight decrease in cadence. Unlike with shorter hills or when running on flat terrain. When we run long hills we cannot maintain the same cadence as the equivalent effort on flat terrain. At the same time we are generating more force per foot strike in order to overcome gravity. So, if we are running at the same power/intensity, whilst running at a lower cadence, then the power per foot strike must be higher.
My own data using the Stryd footpod shows that running power is approximately 4% higher per foot strike when running uphill. That’s compared with the same running power on flat terrain (around a running track). This increase in power per foot strike is due to a similar (~4%) decrease in cadence with uphill running.
Whilst a 4% increase in power per foot strike might not sound significant. The intervals were just over 3minutes long, so that’s a 4% increase in power for every foot strike over the 3minute intervals, or nearly 580 steps.
Unlike short hills and hill sprints these long hills are less beneficial for improving power. Whereas strength is about the ability to apply force, power relates to how quickly we can apply that force. Whilst long hills increase the force per foot strike, they do not increase the speed at which the force is applied. This is due to the slightly slower running cadence (~4% slower) and longer ground contact time (~10% slower) compared with flat terrain intervals.
In this way long hills are a running specific type of strength training that also develop muscular endurance and aerobic capacity. They help to develop strength by increasing the force per foot strike. And because these are run over prolonged periods this brings in a greater element of strength endurance.
Typical energy contribution during long hill intervals:
How to run long hill intervals
Long hill interval training typically involve running a number of repetitions of 1:30 to 5:00 minutes duration. Generally, I prefer to run these for around 2-3minutes duration. It really depends on the purpose of the session and training focus.
One key factor with long hills is the gradient of the hill. Ideally these should not be steep – 3-5% is optimum. Any steeper than this and ground contact time slows significantly which greatly reduces the benefit of these hills.
Long VO2max hill intervals
In terms of intensity these hills are most effective when run at an intensity equivalent, or near to, VO2max intensity. Running the uphills at this intensity, works well with the long downhill recovery periods.
How best to control the intensity? Controlling intensity by pace can be difficult due to the length of these intervals and the gradient of the hill intervals. We can use heart rate to give an indication of intensity although these are generally not long enough for heart rate to be effective. For these I use a combination of running power and awareness of perceived exertion to control the intensity.
For the downhill recoveries, aim to run these at half the intensity of the uphills.
Example Long VO2max Hill Intervals:
- 8-10 x 1:30mins hills at VO2max intensity, 2minute recoveries at half the intensity of the uphill
- 6-8 x 2mins hills at VO2max intensity, 2:30minute recoveries at half the intensity of the uphill
- 5-6 x 3mins hills at VO2max intensity, 3:30minute recoveries at half the intensity of the uphill
Gradient should be moderate (~3-5%)
10k/Threshold hill intervals
Examples include running repeated uphills at 10k intensity, downhills at Marathon intensity. Here this could be run as one continuous set or broken into smaller sets
Example 10k/Threshold Hill Intervals
- 3 x 10 minutes (alternating between 2minutes uphill at 10k intensity, 2minutes downhill at Marathon intensity), 3minutes easy between sets. The set finishes after the 3rd uphill, with a very easy jog down the hill as the between set recovery.
- Alternatively this could be run as one continuous session e.g. 20-30mins alternating between uphill efforts at 10k intensity with down hill efforts at near marathon intensity. Here, the length of efforts could be anywhere from 2minutes to 5minutes. If you’re lucky enough to have access to a long gradual incline you can run longer intervals but here you would reduce the uphill intensity to closer to lactate threshold intensity.
Treadmill Long Hill Intervals
Treadmills can be an effective way to complete long hill intervals. One advantage with using a treadmill is eliminating the need for the long recoveries. Allowing you to run the intervals off a shorter recovery.
Example long treadmill hill interval sessions:
- 10 x 2mins @ 5k intensity* (3-4% gradient), 60seconds easy recovery (0% gradient)
- 6 x 3mins @ 10k intensity* (3-4% gradient), 60seconds easy recovery (0% gradient)
*For every 1% gradient increase, running speed generally slows by ~10-15seconds/mile – depending on factors such as body weight, running efficiency, muscle strength and aerobic fitness. So running pace should be in the region of 30-45seconds slower per mile for a 3% gradient, or 40-60seconds slower for a 4% gradient.
However, you should note that due to the effects of wind resistance (when running outdoors), a 1% treadmill gradient is generally considered the same as running on a 0% gradient when running on the road/track. Therefore a 4% treadmill gradient is equivalent to a 3% gradient when running outdoors.
Long Hill Intervals Summary:
- Long hill intervals typically involve running intervals of 1:30-5:00 minutes duration.
- These intervals work well when run at close to VO2max intensity, combined with downhill recoveries run at an easy intensity (~50-60% of uphill intensity)
- Moderate gradients (3-5%) are more effective for long hill intervals. Steeper gradients significantly slow ground contact time during long hill intervals.
- These intervals improve aerobic capacity, running efficiency, muscular strength, endurance, and fatigue resistance.
- Long hill intervals improve muscular endurance by making us run with increased force per foot strike.
- The increase in force per foot strike is due to a slight reduction in cadence during long hill intervals.
- Whilst long hills are beneficial for strength and muscular endurance they are less effective for training power.
- As well as long VO2max hill intervals, these can also be run as 10k or threshold intensity intervals.
- Long hill intervals can also be completed as treadmill intervals.