What is "target power", and why Xert tells me to accumulate ~15 mins in one session? :O

my “focus power” is ~361W, which is 102% of my 6 min power and 129% of my FTP.
Recent proposed training was HIIT: 30 sec at around 127% FTP and 30sec at around 50% - and 30 times like this !
which means 15mins in total at ~127% of my FTP in one set - to accumulate ~30 XSS High points. Is it even doable?

Hi @razorree, thanks for sharing!

Understanding why Xert recommends a certain amount of High XSS for a training session can sometimes be tricky without considering the broader context of your training program. To provide more accurate guidance, could you please share more details about your training goals?

For example, are you specifically targeting improvements in your 6-minute power as a Target Power goal or event? If so, generating a significant amount of High XSS during your sessions will be crucial for achieving that goal.

By understanding your objectives and the specific focus of your training, I can likely share more specific information. Feel free to share any additional information or screenshots, and I’d be happy to assist you further!

  • Side note 1 - Xert doesn’t work by ‘accumulating time’ at a given power (especially at XYZ% of FTP since that entirely fails to account for individual differences in athletes’ HIE). Instead, Xert looks second by second at your power data (relative to MPA) and determines the contribution of low, high, & peak energy systems for each data point, then assigns XSS based on those work allocation ratios. In order for you to effectively put strain on your ‘High’ energy system, you would want to be riding at an effort somewhere between your ~90s power & ~6 min power, which is where your HIGH energy system contributes the most to your power output.
  • Side note 2 - it is possible to achieve large doses of high strain (XSS) in one activity, but it’s going to be very difficult & require a LOT of carbs. This shouldn’t be surprising since the high energy system is largely powered through anaerobic glycolysis at such high-power intensities (relative to threshold).

Here are just two examples of my (personal) activities that have generated over 37 High XSS - both were done outdoor as sets of all-out 30-30 intervals, which are great for developing your HIE (& VO2max):

~156g Carbs burned in ~90 min of riding

~182g Carbs burned in just ~90 min of riding

The new Program Difficulty setting allows you to control (indirectly) how much high and peak XSS you will get prescribed within the time you have available. The amount prescribed depends on this as wellas on your current high/peak training and recovery loads, your Recovery Demands and your Polarization Level and, of course, your goal/event. (yeah… lots going on to figure out how much training you should do on a given day!!).

Try adjusting the Program Difficulty by sliding it left and then running Adapt. See if the amount of high or peak XSS in your workouts decrease to something that is more manageable for you.

I understand why Xert proposes it. because I chose ‘Rouleur’ profile for my gran fondo (which has only 2 20-25 mins climbs and the rest is flat or small rolling hills - 160km in total).
However I was surprised with that power, before Xert, I was just doing vo2max intervals (which is closer to 115-120% of FTP)

Why Xert is better. :smile: It trains based on the demands of the event rather than on some other more arbritrary single metric. Your event combines longer climbs with flat and shorter, punchier climbs so a 6 minute power focus makes sense. Good choice.