Zone 2 (Also known as BASE MILES) most commonly refers to the 2nd zone in a 6-7 zone scale in cycling training zones.

It’s a lower intensity training zone that’s a step up from a pure “recovery” (Zone 1, useful for active recovery rides and recovery intervals between high intensity efforts) and one below a “tempo” (Zone 3) in the 6-7 cycling zone model:

Zone 2 is commonly associated with a period or phase of the training cycle that’s widely referred to as the “base training” period, and is perhaps the intensity range of choice to strengthen the foundational aerobic fitness which will support higher intensity training further down the line.

In short doing Base training or Base building or Zone 2 training (Its all the same), will improve your anerobic fitness.

75% of your training should be done at 75% of your max heart rate.

Typical ride durations for Zone 2 training will be 2-5 hours for most cyclists.

To induce the desired adaptive stimulus sought from this form of training, rides will need to be somewhat long duration to cause some level of fatigue in the Type I fibres, and ideally deplete muscle glycogen stores to a reasonably low level.

That being said, a Zone 2 intensity can be used in shorter duration ‘maintenance’ rides, e.g. during a recovery week, where it may make sense to raise the intensity above a Zone 1 level but still keep the overall training stress of such a ride low.

The quantity and frequency at which you might train in this intensity zone will depend on several factors, including the cycling discipline(s) you focus on, your fitness or racing goals, your training history, as well as your time availability.

Most cyclists will generally perform between 1-2 Zone 2 rides per week in that 2-5 hour duration range, given that a typical training week will also include 1-2 higher intensity sessions and either active recovery sessions or complete days off the bike.

Remember this is winter training or Zone 2 (Base training), for sportive training advice moving into the spring/Summer look here

Zone 2 training can be performed at whatever cadence is most natural and comfortable for you.

There may be some benefit to slightly higher cadences during some Zone 2 training sessions given that there is some evidence linking sheer amount of muscle contractions to the relevant adaptive stimulus.

Either base training out on the road or indoors is fine.

RECOVERY IS AS IMPORTANT AS YOUR TRAINING, IN SOME CASES MORE SO.