You finished your couch to 5k programme; you ran your first parkruns, maybe a 10k or a half marathon here and there, but you want to be faster. And of the handful of running workouts you can do to achieve that, there is one that’s at the core of speed improvement: intervals.
The deal with intervals
What is the role of the intervals? Let’s take a single mile as an example. You are currently running a mile in 8 minutes. You can split a single mile (~1.6km) in fairly even quarters of 400m each. When you run a whole mile, your split times for each of this 400m should be more or less even of 2 minutes each (8 minutes divided by four quarters).
If you want to improve your speed and get to running each of these segments in 1:30 rather than 2 minutes, you can start with running the first 400m in 1:30, rest for 45 seconds, run the second 400m in 1:30, rest for 45 seconds and do this with all 4 segments. So you achieved running the mile in 2 minutes less than your initial time. The only difference is that you rested three times in between these intervals. If you ran a few times like this, you made your body cope better with running 400m in 1:30. Next, you start decreasing the resting time. Go for 35 seconds, then for 20 seconds, then for 10 seconds and then… there you have it; your body will be able to cope with running all four segments with no rest in between.
No track needed
You see that some of the fast runners and professional athletes in your Strava feed all use the track to do intervals. Why? Well, the reason is simple. Because a very fixed distance allows the coach – and the athlete – to have comparison data with other athletes and with other historical results. Running on a track also gives you that feeling that you’re part of the athletic movement. But you see, when you’re not a professional athlete and when you don’t have a running coach, while it sounds nice, you don’t need to run the intervals on a track.
When you start to run more and more, you can get an idea of how long a kilometre or a mile is without actually having a smart GPS watch around your wrist. So you can also estimate how half of these or a quarter of these measure. In the end, you don’t even have to know the exact distance of a single interval. The most important point of an interval is repetition and consistency. There is no absolute need for a GPS watch or a track. You only need a timer and a fixed distance.
Firstly, find the shortest distance you can run 5-6 times with a short rest in between at your maximum speed possible and in the more or less the same amount of time. Ideally, you’d want to run the first interval slower and get faster as you get tired. But when I say faster, I only refer to 1-2 seconds difference between each interval.
You don’t need to know the exact distance; you only need to run the very same distance every time. Just find some markers in the environment and stick with those. Like from that tree to that bench. You don’t even have to determine a thin line for your start and finish – when you’re at your full speed, the time it takes you to run the length of a bench is not important at this moment.
The recovery/rest time between the intervals should be fairly short. A good rule to follow is to rest half of the time you ran the interval in. So if the interval took you 70 seconds, you rest for 35. This means that, unless you’re running in a loop – which is where the track has an advantage – you will have to run back and forth each interval.
The only requirement here would be that you make sure that the segment is flat so that running an interval isn’t easier or harder than the very next interval. You can do odd and even intervals, where you compare only the intervals done in the same direction, but you should keep it simple at the beginning. Also, find an area or a time of day that is not busy with people because you can’t run at full speed if you need to do lots of zig-zags to avoid them.
Know your limits and push yourself beyond them
It is also important that you know your limits. The basic rule is, if you can’t be consistent with your interval times, you run a shorter distance. Running intervals chaotically isn’t going to improve your running too much. A workout that deems to be chaotic to your body and brain, but yet it’s well planned beforehand is called fartlek. But as far as intervals are concerned, you need to start slower than your average target time and run each interval faster and faster.
Depending on the distance you’re training for, you can do two things after a few identical workouts. You can either decrease the resting time – which I think it’s favourable – or you can increase the distance so that the final distance you’ve run throughout the whole workout is more or less the one you are targeting. Again, it’s ok to go with estimates; you don’t need a GPS watch for this.
The first intervals session should cover at least 5-6 intervals, and you can go up to as many as you can sustain. There is a catch with intervals though. You really need to push yourself beyond limits. If you’re comfortable running your intervals, you’re not trying hard enough. Intervals have to be hard, even hardcore, otherwise the improvement will be a lot less visible or even zero. The questions you need to ask yourself before planning your intervals are:
- For how much time can you run as hard as you can?
- For how many times?
- With how much rest in between?
Warm up and cool down are a must
And one last word of wisdom is, warm up beforehand. Because you’re going to run hard, the risk of injury goes up through the roof, so you need all your muscles to be well warmed up before starting those intervals. A 2-3 miler (3-5km) for warming up would be a good reference distance. Similarly, you need to cool down so a slow recovery run for about the same distance will be good for your muscles and your body in general.