The Anaerobic Speed Reserve (ASR) has been used for many years in sports science and endurance coaching, specifically for running. As usual, it tends to be over-complicated and over-scientific, but the basic principle is one of the most important things that you need to understand as an endurance athlete.
ASR in simple terms is the difference or the ‘gap’ between your ‘maximal aerobic speed’ and your ‘maximal speed’. Ok, so let’s define those 2 things:
Maximal aerobic speed is the speed at which you hit your VO2 max. If you went to the running track and ran as hard as you could for 6 minutes, the average speed would probably not be far off your maximal aerobic speed.
Maximal speed is quite simply the fastest speed you can run, so we’re talking about 50m in distance, flat out. That said, many people use 200m as a bench marker.
The ASR is quite simply the difference in speed between the 2 measurements above.
There is a bucket load of evidence which links the 2 things together. In elite distance runners, there is significant correlation between ‘maximal speed’ and ‘maximal aerobic speed’. In simple terms, the fastest 10k runners in the world, are faster over 200m than all the other 10k runners.
So, let’s look at some simple self analysis. If you’re aiming to run a fast 10k this winter, 2 questions you should ask yourself are:
- Can you run fast? Do you have the basic ability to move quickly over a very short distance?
- Can you keep it going? Is your aerobic fitness good enough to sustain you for 10k?
1. Can you run fast enough?
That question has got nothing to do with aerobic fitness. It’s about producing a high level of force with muscles and tendons. It’s also about nerves, sending signals so quickly, that your legs can move at speed. It’s also about how you land, store energy and push off and it’s about doing all of that, at speed, in a smooth, fluid and relaxed manner. It has NOTHING to do with blood, oxygen and aerobic energy. Running fast for 100m is NOT an aerobic activity and you shouldn’t even be out of breath.
2. Can you keep it going?
Whether you can keep going at a decent speed for 6 minutes, has EVERYTHING to do with aerobic fitness. Those longer and sustained aerobic runs, train your aerobic system to supply enough oxygen (and they train your muscles to need less, which is a bonus).
Here’s a classic example of how this works…
There are lots of runners who are simply ‘not fast’. In relation to point 1 above, they are not able to run 100m at a quick pace. They may do lots of interval workouts and push themselves physically, but if they lack that basic ‘skill’ of running quickly, that will always be their limiter. If you’re attempting an interval session such as 5 X 1 mile as quickly as possible, then if you can’t run 50m quickly, you won’t run 1 mile quickly. It really is that simple.
We’re often told to check our tyre pressure when driving, as soft tyres use more fuel and therefore create more emissions. Well if you don’t have the ability to run fast and fluid over short distances, you are like a car with a big engine but your tyres are flat. Rather than trying to improve the engine, pump up the tyres instead. You’ll probably roll a lot better, a lot quicker and for a lot less effort.
By contrast to this, team sports players who take up running are often very quick over short distances, because that’s their background. Sustaining it for 10k however is another matter. If anyone is going to go off way too quickly in a race, it’s these guys, because the first few hundred metres feels so easy, because they have speed in abundance but they don’t have the aerobic engine to back it up.
What is speed work?
This is perhaps one of the most misunderstood terms in distance running. Speed work should help you to develop your ‘maximal speed’ so being realistic, it should be distances from 50m, up to a maximum of 200m. Running 1 mile repetitions is not speed work. It could certainly be classed as ‘hard work’ but when running 1 mile repetitions, you are far from maximal speed. Many people would become more efficient runners by completing ‘maximal speed work’ (50m up to 200m) and coupling this with easy / moderate aerobic miles.
The Anaerobic Speed Reserve is in fact the basis for ‘polarised training’ which is a term much used. You’re going easy or you’re going maximal. People get confused when they attempt to apply polarised training, as they simply do the wrong workouts. For runners, winter polarised training would be easy aerobic mileage, couple with 50-200m speed work. Hero workouts such as 5 X 1 mile repeats don’t fit into that schedule until much further down the line. The further benefit is that you’re not wiped out constantly as the workouts don’t place a huge stress on your body.
Triathletes… You can also apply this exact same principle to swimming and cycling. For swimming it’s 25m sprint speed coupled with aerobic volume. For cycling it’s 10-30 second power output, coupled with aerobic volume. In some ways it’s easier with swimmer and cyclists as the injury risk associated with maximal swimming and cycling, is far less than maximal running… That is of course an issue which must be addressed and maximal speed must be applied correctly.
The message is simple, if you cannot ‘run fast’ in its simplest form, for a very short distance, then you can’t do it for ‘any’ distance. Develop the basic principle, or it will always be a limiter for your performance. Marathon and ultra runners… you may well think this isn’t for you and it’s possible that you’d never consider short distances of 50-200m. Do not underestimate the benefits of such maximal speed work. The impact upon your running efficiency at lower intensities is significant and for many people, it’s the missing piece for break through improvements.
If you have any questions, please comment on the Facebook page.
We offer coaching from £40 per month for Lakeland 50 & 100 runners, triathletes, marathon and ultra runners. We also offer lactate threshold and VO2 Max testing with consultation for £60, to help you better structure your training. Find details on the menus above.
Regards
The Endurance Coach