The Great Base Miles Swindle

In the late 17th century the western world was cleansed of its belief of witches, black magic, gnomes and elves and other such mumbo jumbo by the enlightenment. However it failed to sweep away the myth that winter is the time to get in the dreaded BASE MILES!

We’re getting to the time of the season when the racing stops and cyclists all over the land don hairy legs and panniers and religiously ensure that every ride that they do is no more intense than a vigorous brew stirring. All in the sure fire knowledge that when spring comes round they’ll have a strong base of aerobic fitness on which to build a world beating season on. I used to work with a guy who had a very good term to express my thoughts on this concept. “What a bunch of arse”.

Imagine a gym full of chiselled muscular men and women pumping iron. Most of them work to a plan of progressive overload. I.e. they lift a certain amount over a certain amount of reps until their bodies adapt to that load and get stronger. Then they up the challenge again – maybe heavier weights and lower reps or the same weights and higher reps or shorter recoveries. The combinations are endless but ultimately they are constantly challenging themselves over time. Years and years pass by and they get stronger and stronger. This is how you create a deep, strong foundation of strength.

Now in walks the guy who used to advertise Mr Muscle furniture polish in his string vest. He comes in every day and stands in front of the mirror for around an hour doing bicep curls with an unloaded barbell. This guy is a man with plan. He’s going to develop a deep base of strength with this tried and tested principle of cycling folk lore and then after a few months he is going to be able to bench press double his body weight.

Silly isn’t it?

Yet somehow this strange concept still hangs around. The term base fitness doesn’t really mean anything. If you have a cyclist who in the season has a threshold power of 300 watts and has let that drop to 250 watts and now is capable of doing a 5 hour ride at around 160-170 watts does that means the cyclist has a great level of base fitness but still needs to work on their top end (whatever that actually means). No. It just means this cyclist is very unfit.

Instead of thinking of base fitness think of the term base line fitness. Base line fitness is the fitness level that you are used to. For those familiar with the performance management chart in training peaks this probably best encapsulated by a riders chronic training load – CTL.

Basically every ride you do be in a long steady ride, a time trial, a road race, a commute or whatever generates a level of stress. This level of stress is known as a training stress score – TSS. Over time the rider gets used to a certain level of stress. As a very simple example imagine that for every week for a few months a rider rides their bike every day for around an hour at a very steady pace and each ride generated a TSS of 50 points. After weeks and months they would have a CTL of 50.

That would be that rider’s base line fitness. Another rider may do twice that much and not just steady rides. They may be used to doing 10 or 12 hours a week of riding with lots of intensity and long tough rides. They may well have a CTL of 100 or more and to all intents and purposes that is there base line fitness.

Let us now take the latter example who is at the end of their season and is looking to build fitness for next season where they want to really set the world alight.

They tell their coach that they have a maximum of 12 hours a week to train. So the coach thinks – well we won’t use the full 12 hours yet. We’ll build up to that. What we’ll do is start of at about 6 or 7 hours a week and gradually work up to 12 over the course of the winter. We must build a really strong base of aerobic fitness so we’re going to keep all the rides really steady below 80% of FTP.
And there is the big swindle that will ensure that the rider makes no progress from season to season.

Their rider will diligently go about their work, keeping that intensity down, with rides that’s simply don’t generate that much training stress.

All the while that rider’s CTL is steadily descending down and down and down. This rider is not building a base of fitness. This rider is surely and steadily lowering their base line fitness.

Spring then comes around and the rider who finished the season with a CTL of 90-100 has now steadily built it back up from a low of around 50-60 in December, back up to around 80. Few early season races and some grippier rides and this rider’s threshold power is pretty much back to where it was and their CTL is back up to around 90-100. Result. A winter gone and back to exactly the same place they were before.

For some being exactly where they were may actually be a pretty good thing. If you’ve pretty much reached the limits of your genetic potential (with the time you have to train and recover) trying to remain at that level or even push it on through the winter may be counterproductive. It could well result in just feeling tired and jaded and actually going backwards.

So for some riders you may actually actively want to lose some fitness with the express intention of making no progress.
I would say that this applies to a minority. Most people, especially riders who have not been in the sport that long want to make progress from season to season. If this is you and someone tries to sell you the big base miles swindle just politely shake your head and walk the other way.

The body needs to be asked questions otherwise it will not get any fitter. You can either be gaining fitness, maintaining fitness or losing fitness. If you are doing base miles and your CTL is dropping then you are losing fitness. It is as simple as that. You’re building nothing.

But what about the pros? They do lots and lots of base miles. Yes they do around 20-30 hours a week more often than not. That kind of load even at a very steady intensity generates a very big training stress which asks the body lots of questions. As the Russians said in world war 2 when they were churning out T34 tanks at a rate of hundreds a day “quantity has a quality all of its own”.

It doesn’t automatically follow that the typical amateur cyclist with around 10 hours a week or less will be able to generate the same sort of training stimulus by training in the same way. Even if you did have the hours (and the genetics) to train like a pro would you want to?
Could a pro achieve the same level of fitness and by fitness I mean development of V02 max and threshold power by doing half or even a third of their training hours at a higher intensity? I would stick my neck out and say you could but I don’t think anyone has ever tried!

A base of fitness is simply a level of fitness that your body is used to. If you want a higher level of fitness you need to challenge your body by teaching it to work at a higher level of fitness. That can only be achieved by consistently asking it questions all year round and making sure those questions adhere to the principles of progressive overload and adaptation.

If it doesn’t you may be being swindled from developing from season to season due to the oldest trick in the book!