From 1st Cat to Elite: A Weekly Training Diary #8. Why Z2 isn’t Easy

Easy sessions are important (you’ll be glad to hear). Most people following a zone based training program think zone 2 is easy. But i’m here to tell you why it’s not and explain why zone 2 is your friend.

Zone 2 is the staple diet of many endurance athletes. As the training volume increases, inevitably the intensity has to come down or you’ll implode. For those not familiar with Zone 2 it’s defined as being between 56% and 75% of your FTP according to Dr. Andrew Coggan’s Power zones. If you work with heart rate then it’s between 69% and 83% of your lactate threshold heart rate, or typically around 70% of your max heart rate. Or for the less geeky amongst us, a long slow distance type pace you can ride at all day.

Sounds easy right?

Well, I get that a lot. ”Zone 2 is painfully easy”, ”God, Z2 is slow”, ”I tried to stick with Z2 but got bored and did some sprints”. Those people are usually doing it wrong (it’s not their fault, you only know once you know). Z2 is easy if you coast down hills, stop pedalling all the time and take breaks. But if you sat on the turbo, started riding in Z2 and didn’t stop for 3 hours, you wouldn’t be telling me it was easy.

Z2 requires focus, concentration and technique to get it right. Fair enough, it’s not the most physically taxing of intensities but it is still a vitally important one. Spending time in Z2 allows you to continue to improve your aerobic capacity whilst recovering inbetween harder rides… and YES, you need to take a recovery drink after a Z2 ride!

It typically takes about 2.5hours to fatigue your slow twitch muscle fibres whilst riding in Z2 so it’s not a quick fix. The time crunched athlete working on 5-6hours per week won’t usually get all that familiar with Z2. 6 hours of Mid Z2 will only accumulate around 300TSS. A weekly TSS of 300 isn’t going to get you very far if you intend on becoming a competitive racer or faster cyclist.

For those who ride more weekly hours and hit bigger TSS scores then Z2 time will show it’s face. If you get bored in Z2 I suggest bringing other elements in to focus on. Try hitting exact normalised power figures, 50/50 left right balance, exact calorie consumption/work done goals, or try focusing on good form and pedal technique. You can always do one step better than just blindly riding in one zone and listening to your favourite Cher album with one headphone in.

The reason i’m wanging on about this is that my week has pretty much solely consisted of Z2 as i’ve had a major recovery week. I was way too fatigued from a big build phase and have a pretty important fitness test coming up in 3 days time so would like to be as fresh as a daisy. I’ll be making my way up to Liverpool on Wednesday for some lab testing with the Land speed record project guys. Hopefully the last 2 months of hard work pays off and I put in a big old performance. Time to go to that deep dark place you only visit once or twice a year, and I don’t mean Liverpool.


Dropping CTL is not a backwards step. It’s an important step forwards in recovery and allowing your body to repair and get stronger. Evidence of which can be seen in my Friday Wattbike session where I spent 30 minutes in Z3 power but the heart rate only crept up into Z3 for 11 minutes. A great sign that the legs are back and freshness is a plenty.


Happy December everyone! if you haven’t yet tried to figure out where you need a rest week so that you can allow for some extra Christmas riding time then now would be a good time to do so.

Thanks for reading and as always, please get in touch with any coaching questions or for some advice on your training.

Peace out and ride safe,

Coach Ken

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