I have previously mentioned using the Xert software and the basic concept is that it monitors 3 variables (peak power, threshold power (FTP) and high intensity energy) to produce a fitness signature.
Once a signature is created then Xert looks at your workout results for indications of when that signature has changed. The most common ways of updating a signature are to exceed previous peak power or to push very hard over a period of time such that maximum available power is lower than current power and by definition your MPA must be higher than it started out and you get a breakthrough (BT)
There are a number of workouts designed to do thatĀ – search breakthrough on the workout lists – I reccommend Xert Fitness Test for Breakthrough which is 72 minutes long.
However today I did not have a lot of time and I had heard of the dreaded Ronnestad workout which Stephen Cheung talks about on theĀ Xert Lab podcasts which I highly recommend listening to. This comprises 3 sets of 13 * 30 seconds on (130%) and 15 seconds rest. It is as hard as it sounds.
I had also read somewhere that you only needed to complete one set to gain a BT. So that was the plan. This is my workout below, I warmed up for 10 minutes and then started out on the 13 intervals. My targets were 30 seconds at 329w and 15 seconds at 129w. I started in slope mode (2.5% resistance) but it was too erratic and so I moved into Erg mode for the first 12 intervals then switched back to slope for the last one so I could push as hard as possible.
I worked hard on that interval (knowing it was going to be my last) and actually hit 415w at my peak (MPA was 422). You can see that MPA continues to drop even though I am easing off the power slightly.
Below are the numbers at the point of breakthrough and you can see that power is above MPA by 4w. I then eased off and did the next rest interval of 6 minutes to have a good workout in 26 minutes. My Garmin advised I would need 23 hours to recover from that session. Not sure how accurate that is and what the exact definition of ‘recover’ is
Session lasted 26 minutes (48XSS or 36 TSS) and I was very happy with it. I could certainly have carried on and done at least the next set of intervals but I am not sure what the point would have been.
My fitness signature details before and after are below. Peak power reduced as I did not get near it, threshold power increased by 5 watts and HIE reduced. I would love to explain HIE but I am afraid it is a concept that I do not really understand. I do know that if one varaiable goes up at least one if not both of the others must come down.
I love numbers and data and Xert definitely gives plenty of those. It is a facinating tool and one that I think is well worth trying.
Enjoy the Ronnenstad intervals.