I just started using the plan a month ago and my current zones are based on previous threshold tests that are quite dated (likely from 2019). I have RT16 and CT30 this week which I’d like to use to establish my TP (run) and FTP (bike). How do I do that with a tempo workout? I’ve read the section in the intensity guidelines, but how do I actually execute the workout? Both are 20 minute Z3 efforts, so do I stick to Z3, or really just go as hard as I can for the 20 minutes? And what do I do with the data after to establish my zones? Plug the threshold pace/power and LTHR in the zone calculator, or in Training Peaks?
Thanks for using our plans. Particularly with the RT16 and CT30, these can be the 20-minute alternatives listed in the Intensity Guidelines docs. It’s a 20-minute time trial, so go as hard as you can maintain for 20 minutes. Then, you take 95% of that value to determine threshold. 280 watts for 20 minutes becomes 266 FTP (95% of 280). 10 miles per hour over 20 minutes becomes 9.5 miles per hour threshold pace.
Thanks so much for your response David. This is very helpful.
For determining cycling LTHR, the intensity guidelines indicate doing a 30 minute test and taking the average HR for the last 20 minutes. Could I apply the same logic to the 20 minute test and just take the average HR for the second half? Do I also apply the 95% rule to the average HR?
HR is treated differently than Pace (outcome) or Power (output). We take the peak 20 of a 30-minute test because we recognize that HR is a lagging indicator and needs time to “catch up” to the intensity. That typically happens in about 10 minutes at LT pace. The 95% rule on the 20 minute test just works for Pace and Power.
The 20-minute test really does not work for HR, you really need 30 minutes for HR. Or, if you have an idea already of your LT Pace or Power, then you can hit that Pace or Power and wait for HR to plateau to establish LTHR.