Back when I started out, more experienced runners would tell me to run mostly easy so that I could build my base. I would just stare back in disbelief as I gasped for breath, feeling my heart pounding in my head from running just a couple of miles at the only place that I could manage that wasn’t walking.
What is base building? Base building is the term for increasing your aerobic fitness level. It is the foundation on which all other endurance sports fitness is layered. Without a strong aerobic foundation, it is near impossible to hold fitness levels for a long before overtraining and illness knock you backward.
Trail Running And Aerobic Deficiency Syndrome
Before you panic, this is not some sort of fatal disorder or virus. It is a completely reversible condition but is something that almost all of us trail runners face at some point or another.
The trouble is that running uphill is almost always at or close to your maximum heart rate or maximum output level.
When I’m in the mountains I spend a disproportionate amount of time going uphill because it takes that much longer. That, in turn, means that I spend a disproportionate amount of time with my heart rate pounding in my ears up at its maximum possible level.
You treat aerobic deficiency syndrome with a strong aerobic base.
How Important Is An Aerobic Base?
When we start out as runners and trail runners it seems very unimportant to have an aerobic base. After all, the first distances we do when we start out are 5K and 10K runs, then building up towards a half marathon distance.
Your body can store enough glycogen for around 90 minutes at your maximum effort. If you smash in a gel or two you can extend that glycogen window a little further.
That means that we never feel the need to go slower because we finish all our workouts and training runs before the tank is empty.
If your event or project extends beyond 3 or 4 hours, glycogen and gels just won’t cut it anymore.
When I run I can digest around 300 Calories per hour but I burn around a thousand calories per hour when I run. At some stage, the tank is going to get empty, or as Lance Armstrong puts it, at some stage the man with the hammer comes around and hits you flat on your face.
We all have a massive reserve fuel tank called body fat. The trouble is that you need to train your body to use it.
Your body can metabolize fat at an aerobic intensity level but if you don’t train an aerobic base you will have no aerobic intensity level to rely on. In other words, you won’t have the intensity level that you can switch to in order to be able to start burning that massive available fuel source that is body fat.
How To Train An Aerobic Base
For me. the most effective way to train my aerobic base has been at what’s referred to as MAF level training.
It’s a system devised by Dr. Phil Maffetone where you calculate a heart rate based on fitness level and age. The value you calculate will be the maximum heart rate that you use for your training.
The basic rule for calculating your MAF heart rate for training has been described by experts as less than completely accurate. However, the results of testing athletes in a laboratory have shown that their aerobic threshold is at most only 3 beats per minute different to their MAF score.
To calculate your MAF heart rate deduct your age from 180. In my case that came out at a level of 129. So my level of training will be limited to keeping my heart rate no higher than 129 beats per minute. The first couple of times I tried that it required a lot of walking to keep my heart rate that low.
Even today the only way I can keep my heart rate consistently below 129 is when I am running on the flat.
If you lived where I do, in the mountains, where just about everything is either uphill or downhill. The only way I can be sure to run on the flat for an extended period of time is by running on the treadmill.
The trouble is I love running out in nature. Treadmill running is a very sub-optimal form of training especially when I look at it from a motivational perspective.
Play In The Mountains Like Killian
There is no denying it. We all know that killing Jornet is wicked fast. Even though there is no way either of us can keep up with him in the mountains, there is something that I could learn from him.
In training, I tried using the Killian “play in the mountains” method. I walk up the hills without shame because when I walk I am slow enough to keep my heart rate down at my Mafetone level pace of 129 beats per minute.
Once I get to the top of the hill I can then, as Killian puts it, play on the downhills. Doing that improves my downhill running skills as well.
