First TT ever where I had proper data to use to try to do my best time. Went out with the idea that I’d sit on 156BPM (Fitlab tested anaerobic Threshold) for the 40 kays. I figured that this would be right on the point where my body could clear the lactate without accumulation (they call it OBLA or Onset of Blood Lactate Accumulation). At this point the testing says I put out about 365 watts. A straight flat average road would mean a time of about 53 min at that wattage with my bike setup, but taking into account the slow road and rolling bits in the course and based on numbers from BikeCalculator.com and Analytic Cycling.com I was gunning for around 57min to be realistic, maybe 57.30 – 58 with the wet conditions and the turn.
I did 59.09, and averaged 161 BPM. So what’s that about? Well, actually that’s fine. The extra minute equates to about 40 watts, and its entirely possible that between the nature of the course today (some gravel), and most importantly the change in position I’d lose that amount. Obviously working on my position with a power monitor would fix that, but the fact is my budget stretches to Clip on aerobars from Torpedo 7 – and, er, nothing else.
My HR was about 5 BPM higher than anticipated but in hindsight, that’s probably right since in a race situation you actually DO want to build the lactate and totally exhaust yourself, without cracking before the finish line. Actually, I’ll aim slightly higher next time for that reason. In a TT you don’t want to ride at a pace thats sustainable. You want to go a little over that so, ideally, you leave everything on the course and blow chunks all over the bystanders 20cm over the finish line. I felt like I was really trying to hold myself back over the first 20KM especially and could have been faster there – I was too concerned about blowing up but in hindsight I don’t think that would have happened.
Check this out for a good analysis of gear bang for buck in the TT aero world:
Andy Hagan won with around 56.30 from memory – so thats about 150 seconds faster over the 40KM give or take. That means (based on the chart) if I had my shoe covers on, aero wheels and a TT helmet the times could have maybe been neck and neck, maybe.
I also looked back on some data from a 2up TT on the same course back in 2004. I did, literally, EXACTLY the same heart rate (161 avg) for an average speed around 1km/h faster (due to having another dude – Mike Milner I think it was) What does this tell me, er, I dunno. I guess in 10 years having the same HR in a TT is a good thing.
Learnings: Aero gear works and makes the difference. But it costs. Worth it if you are doing big races I guess. Heart rate – going to go for around 165 average for the hour next time, for the reasons above.
I will take up my mates offer of his TT bike next time and do some comparisons and report here if this theory actually works in the real world or not.