Cycling Training: The Zone Two Myth and the Importance of Polarised Workouts

Zone Two training is all the rage in the cycling world at the moment. It has been shown both scientifically and anecdotally by the World’s top professionals that this, steady but easy effort level, is the most effective training intensity and produces the biggest gains. Many have grabbed onto this training approach like a thirsty man in the desert grabs a water bottle. Afterall, a zone two intensity is relatively comfortable, it is one where we can still chat fairly easily to the rider next to us. It is much less painful than smashing out sets of intervals but, for racing cyclists, is this really going to do the trick?

What many overlook when they read about Tour de France winners doing the majority of their training at zone two is that these athletes have no limits to their training time and are generally, racking up thirty hour plus weeks, one on top of the other. Most of us are lucky if we can squeeze out ten hours in our busy weeks and should we then be doing all of that in zone two?

The other aspect to this training approach, emulating professional cyclists, is that they race almost as much as they train and trust me, they are not racing in zone two. Their training takes the form of a more polarised approach. So, lots of steady, relatively easy long rides at zone two, punctuated by intense racing where a lot of time is spent at zone four (anaerobic threshold) and above. In the run up to the season, before racing starts in earnest, they will definitely also include intervals at those higher intensities to prepare the body to make those efforts on race days if their goals are to perform early in the season. Those looking further down the line will probably not have to do much interval training and will use early season racing, where they are not expected by the team to perform, to build the race intensity for their target events.

Back to us, weekend warriors. We certainly can’t race as much as professional cyclists do and, when we do race, the event is always important and one we want to perform at our best in. So, rolling to the start line having done hours and hours of exclusively zone two will have us comfortably covering the distance and finishing strongly but it will not have given us the snap to follow a rivals attack or even the group we are with, accelerating up a steep climb. Those types of efforts require a VO2 level exertion, our five minute maximum power output. To do that in a race, we need to have done that in training.

After a race acceleration, for the move to stick, a high, sustained effort is required to consolidate and grow our gap. If we were caught on the back foot when the acceleration happened and we find ourselves having to ride ourselves back onto the group, the same effort is required. This kind of effort will see holding power and heart rate levels that equate to our anaerobic threshold or ‘functional threshold power’, this also needs to be worked on in training.

You can see where we are going with this. While zone two is definitely a very important training intensity level and one which lays the foundation for the more intense work that should follow, it is definitely not the be all and end all of our training programs. As our key races approach, our training should become more and more relevant to the efforts that we anticipate we will be making in those events. We should then start incorporating intervals or fast group sessions into our weeks, but these should definitely not override the whole week. The bulk of our training should still be at those comfortable, steady effort levels, punctuated with shorter, much more intense efforts that will prepare our bodies for the intensity of racing.

What we want to avoid at all costs is ending up in the grey area between these two intensity levels. Logically this would be zone three, somewhere between two and four. Without getting to tied up in the numbers, simply put, we want our easy to be easy and our hard to hard. Many make the mistake of riding too hard on the easier sessions for the bulk of the weeks riding. This compromises our recovery, leaving us fatigued and not able to perform at the levels we are looking for when we do our zone four and five level intervals. So, the difference between our easier riding and our harder riding is not as wide as is ideal and our training is not as polarised, which is where we are aiming.