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Build 2 - Week 1: The VO2max rude awakening and more fatigued efforts.

As predicted in the last post, having completed a solid amount of sub threshold efforts in the preceding months, the first few VO2max sessions were going to be tough.


A little z2 for 1.5 hours with Bowie Brevet in Zwift. Not too much to report here, other than a new route for the pace partner (something which was welcomed after so many miles on Sand & Sequoias with this chap!), but this felt nice and civilised, averaging low z2. Good start to the day.


The first session definitely exposed that, and with 6 x 3 mins @120%FTP in the plan for Tuesday morning I definitely realised it's a case of "use it or lose it" at this intensity. It's fair to say that in training I've always dealt with shorter repeated intervals at VO2max than I have with the typical 3-5 minute repeats (I find them psychologically easier to break down and get through), but even so I was expecting to get through this one.

I cleared the first interval at 120% FTP (385W), but it was already a grind and with a 1:1 Work:Recovery ratio, it wasn't long before I was struggling through the second. However, I only made it a couple of minutes through that when my brain decided it didn't like the pain. I elected to reduce the power target for the third interval, and got through that at 370W, but even through that one, mentally I wasn't quite up to suffering today and feeling the burn halfway through the fourth interval, I pulled the pin.

I was fairly sure this was "mainly" a mental failure in dealing with a fairly "new" type of pain (in recent times), so decided to ride a tempo/SS ramp block to round out the session and see how were my legs really were. I got through this with a relatively low perceived exertion, further backing up the thought that it was the new stimulus which was really the issue. Also, the tempo/SS is a lot more glute/hamstring focused for me, whereas the VO2max efforts demand more of my quads as I go above threshold.

So it certainly wasn't the start to the week I'd hoped for, but it wasn't entirely surprising. I do find that the first intense session of the week can also be a little flat after a few days of de-loading, and as I age as an athlete, I find I respond better to sessions with a bit of fatigue in the system. So with that in mind, let's roll onto Wednesday (my non working day of the week) and get another session in!


Typically I get a couple of longer z2 endurance rides in a week, one on a Wednesday, and another at the weekend (often Sunday). I still got some decent z2 miles in, but after yesterdays VO2max woes, I wanted to accrue some more time in the zone. I elected to do this in more "bitesize chunks" than the straight up 3 minute efforts of the day before. I've had some good success with 30/15s in previous builds, so started with a block of those. At my peak, I was performing 3 sets of 13 reps at 125% of FTP, but thought I'd go with 3 sets of 10 at 120% of FTP to ease into it. Having got through those relatively unscathed, I took some recovery in z2 for 30 minutes before adding in 3 sets of 10 minutes of over-unders (one minute over, one minute under). My idea being here that I would get a little more time in z5, and also get used to the pain of doing this with a bit of fatigue already in the legs. I didn't target anything too aggressive in this block given the earlier fatigue, so went with 105% FTP / 88% FTP. These also went pretty well, and as is often the case with these efforts, it's actually the first 10s of the under which are the most painful (especially if you're going from out of the saddle back to seated). I was pleased to have achieved some more time in zone 5 in this session, and rounded the days training out with some more z2 endurance before heading into a recovery day on Thursday.


For Friday's pre-work session, the coach had scheduled some z6 anaerobic work. A good chance to build some strength and some anaerobic stamina with two blocks of 6 x 30s at 150% FTP. I found towards the end of last year (with races in Zwift on routes like Richmond etc) that my anaerobic repeatability is actually quite solid (not something typically associated with a time-trial phenotype), so I had confidence going into this session. That confidence seemed well placed, as I got through the first set comfortably (focusing on a solid core and power transmission through the pedals). I decided to increase the intensity bias for the second set to 105%, and even ramped the last two efforts to 107% and 110% respectively to put the cherry on top of the session. A little more z2 to round out the session and then get the working day started.


Saturday saw the most strenuous, and final prescribed session from the coach. This one was the most "event specific" (current A race of the year being around a 6 hour effort). This 4 hour session started with 4 sets of sweet spot with surges (2 minutes at 90% FTP, followed by a 30s surge at 120% FTP). These went well, and I felt very comfortable at sweet spot, and strong during the surges (surges completed out of the saddle).

There was then a 5 minute recovery period before a 5 minute effort comprising 2 minutes at 115% FTP, one minute of z1 recovery, straight into another 2 minutes at 115% FTP. This effort was certainly tough, but I was pleased with how I got through it, not least of all so close to the 4 sets of SS surges.

A nice 30 minutes of respite at the z1/z2 boundary, before entering into a "tempo grind" segment. 30 minutes at 85% FTP, with a prescribed cadence around 80rpm (which is relatively low for a "spinner" like myself). This effort definitely got the attention of the glutes and took a little while to settle into, but actually got easier over time. This effort was followed by a further 30 minutes at the z1/2 boundary to recover, before repeating (what I expected to be) the toughest 5 minutes of the workout. A repeat of the earlier 5 minute VO2max block...

As my legs were feeling a little cooked after nearly 3 hours of efforts at this point, I decided to disengage ERG mode and go with "best endeavours" for this effort. I was pleased with my numbers for the first two minute effort, but the power started to drop a little during the second two minute effort, so I knocked it on the head so I could finish the rest of the workout.

Another 30 minutes of respite at the z1/2 boundary was followed by another 30 minutes at tempo (favouring low cadence), this time, at a lower power of 80% FTP. This was again a bit of a grind with 3.5 hours and a bunch of efforts already in the bank, but I was pleased to get through without too much discomfort.

Given that I had riding plans for Sunday, I decided to give myself a long 30 minute cooldown in z1 to really flush the legs out as much as possible before hitting the recovery (read as feet up in front of the TV) hard!


I planned to do 4 hours of z2 on Sunday (preferably outside after a week on the trainer), and the weather looked good. With the easing of lockdown restrictions, my club group rides had started again (with no more than 6 riders per group). Although the route was a little lumpy and not entirely conducive to a pure z2 ride, I decided the opportunity to catch up with some mates and enjoy the sun was too good to pass up. I set out with the aim of keeping the climbing below threshold, and just enjoying the flats (as few as they were) and the descents.

The plan worked well, and I built up around 40 minutes of tempo and 15 minutes just below threshold over the course of the 4 hour ride, and it was mostly z1 everywhere else. A lovely route taking in familiar (but not recently visited climbs) and a lovely way to round out a solid training week.


A solid week of training on the bike, but definitely an eye opener in terms of my VO2max limitations. Next week will see some more work on that with some two minute repeats, some more race specific above threshold efforts, and another longer (3 hour session) comprising a good number of anaerobic repeats and some time working at and just above threshold. I completed my usual strength sessions in this week too (comprising 4 x 40 minute sessions) - If anyone has any questions on the specifics of my strength and conditioning work, then feel free to post a comment and I'll give some more details on that.

Week totals

So, that wraps on Build 2 week 1, we move onto week 2 where we attempt to take more steps towards improving the above threshold efforts again.

I hope your training is going well, and until next time... Ride On!

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