Curious about Training Status change

Hi all,

Having had a decent start to the season interrupted early on by a broken rib (non-bike-related) and a badly-gashed knee (crash during race), I’ve put in a good run of training and have had decent form of late. Looking at Xert last night, I saw that I hadn’t had a breakthrough since March, however, and my FPT of 307 seemed off. I then noticed in my profile that I had left Signature Decay Method to No Decay.

I switched to Optimal Decay and it reassessed my fitness signature, adjusting to a more realistic FTP of 280, jumping up to 286 after a long-delayed breakthrough following a Zwift race last night.

What I’m curious about, however, is that my training load, according to the stars indicator, has increased significantly following the change of fitness signature, going from two stars plus a tiny bit into the third star (forgot to check the actual numbers) to almost three full stars. I can see why FTP, Peak Power and HIE was adjusted, but wouldn’t the load have remained the same?

Training load is relative to your signature, so lowering your signature means that you were working relatively harder than originally thought. Eg very roughly, riding at 200w was around 60% of your TP but around 70% of your new one.

The other reason it changed is that switching to optimal decay is back-dated to your last BT so is applied to past workouts i.e. it isn’t just applied instantaneously / going forward