Originally written for RaceCenterNW Magazine.
Everyone has heard the old adage: "before you do intensity, you need to build your base." While there are a few things to consider between individuals and training plans, that's basically true. Base training lays the foundation for the training and racing that follows, allowing you to reach your target events fully recovered and in top form.
Think of your fitness as a house. The attic is peak form – the very top. The second floor is high-level VO2Max fitness, while the first floor is LT (lactate threshold) fitness. In order for all of this to stand up and for the structure to be solid, it needs a good foundation. Your aerobic base is the foundation for your "fitness house."
So, does this mean that you ought to spend the whole winter riding around at nothing above your Endurance Level (often referred to as Level, or Zone 2)? It most certainly does not. What it means is that the bulk of your aerobic training, whether it is swim, bike or run, should be at your Endurance Level. It's still important to do a bit of LT and VO2 work in the base-building period, because doing those boosts your aerobic fitness and also your ability to recover between workouts and, eventually, races. This can be done either in your primary sports, or in the gym, or even with some cross-training.
Let's have a look at what a typical Base Period week might look like. Monday is almost always a good day to take complete rest, after the weekend of long endurance workouts. On Tuesday, Wednesday, or Thursday, take an easy (Level 1) day. On the other two, choose one and make it your LT or VO2Max day. It's only necessary to do one day per week of this type of training, at most. Also, it isn't necessary to do more than one or the other in a given week – alternate weeks with one containing an LT workout and the next a VO2Max workout. Then, take Friday off and relax. You'll be well on your way to building a solid endurance foundation.