Endurance rides: the why and how

Endurance riding, that ugly duckling of training. It should be a big part of our training, but it isn’t often talked about in the blogs and podcasts. Endurance training isn’t sexy like HiiT training, but taking some time to develop your endurance system (which almost no one does) will help make you a better rider.

Why endurance?

While most of the talk in the cycling world is about the sexy side of training - intervals, FTP, and hard riding in general - it is actually the endurance/aerobic system that underpins all of your efforts. We have this idea of two systems, anaerobic and aerobic, working independently. The reality is that they work together all the time. And even when we go hard the efforts quickly become mainly aerobic. You can see in this shot that after only 1-minute the aerobic system is doing most of the work to fuel the effort.

Adaptations

Our endurance training helps us develop some key physiological adaptations:

In the muscles we see increases in:

• mitochondrial density and function - the mitochondria are the “powerhouse of the cell”, creating energy through aerobic processes. The more the better and they thrive under aerobic training.

• capillarization - more blood vessels to deliver oxygen and remove waste

In the cardiac system we see increases in:

• stroke volume and cardiac output - you can move more blood with each beat of the heart

• capillarization in the lungs - more blood vessels to uptake oxygen

These physiological adaptations can be thought of as structural changes. The hardest part about endurance training is that it takes time for the changes to happen - years of training. And the changes do not happen in any sort of linear fashion. Often riders experience sudden bumps in their aerobic abilities, there is not a consistent progression that happens.

How?

The key to real endurance training is the idea of intensity discipline, as outlined by Stephen Seiler - when doing endurance stick to the zone, even if that means going really slowly on the climbs. Going easy up the climbs means using your power meter as a governor to keep your effort in check. It can be a bit frustrating at first until you get used to the pacing.

Very few riders actually ride real endurance rides. They are on the easy side of things, with little to no muscular fatigue left in the legs the next day. A proper endurance ride should have:

An almost flat power line when the ride is graphed in Training Peaks:

A Variability Index (VI) <1.05 and and a power to heart rate ratio (PW:HR) <5%.

We can also think of our endurance rides in terms of what they are doing metabolically. The thought is to try and promote fat burning on these rides. Our intensity discipline is key to this. We need to keep the effort appropriate to keep our body using fat as the primary fuel source. When we go hard on those short climbs - riding well above our endurance wattage - we turn on our glycolitic (sugar burning) systems. Even though once you are over the climb you go back to your endurance wattage that doesn’t mean that metabolically you return to a primarily fat burning state. That glycolitic system you have turned on doesn’t just turn off, it stays fired up for a while. If on each climb you punch it a bit, you are missing out on the metabolic goal of this type of training.

By heart rate or power?

A common question deals with whether power or heart rate should be the guiding metric. There is no clear answer on this as it depends on the type of rider you are. In the blog “The workouts don't change: who you are as a rider changes how you should do the workouts” we have defined three types of riders. Each will approach an endurance ride differently:

• Riders needing more watts - watch the heart rate as you will likely get into the endurance zone fairly quickly. You want to do your best to stay in it.

• Riders that are fairly fit - start by power, never at the top of the zone, and let the heart rate catch up to the effort. As the heart rate comes into your endurance zone adjust your wattage accordingly. On a long enough day this is somewhat like a tempo ride where the wattage may come off at the end.

• Riders that are very fit and talented - power is your guide, and probably at the bottom of your endurance zone. Anything higher will make the ride too hard and leave you with muscular fatigue. Riding your endurance rides this way will leave you tired when it comes time to do your efforts.. You may find that the heart rate stays in your recovery zone for a good chunk of the ride and this is OK.

Many riders get frustrated and think that the endurance rides are too easy. They want to see change and this type of training adaptation takes time, years in fact. There is value however in taking the time to develop your aerobic/endurance abilities. Make your aerobic system better and all of your efforts, up and through to your hardest ones, will improve.