Research on Training Periodization

This research report was released which what very well designed and studied various 16-week training programs (112 days so very close to the Xert 120-day program) and concluded that the best approach was to do the first half pyramidal which essentially meant to focus on Endurance but included efforts near and below TP and the move to a polarized method for the second half of the program which had easier efforts below LTP combined with high-intensity training.

This very much in-line with how Xert periodizes the existing Training Program but rather than make it a clean break midway, it gradually moves you from a focus on Endurance to your Target Athlete type over the BUILD phase, in essence making your training more and more polarized during that phase. Although this specifically wasn’t part of the research study design, one can conclude that a program that starts with BASE and ends in PEAK according how Xert does it, would likely provide best results.


Would be nice to see the study duplicated with cyclists.

You could possibly look at research that compares exercise modalities and their similarities to help with applying the same conclusions to other types of endurance sports.

Thanks for sharing this study! Do you see any interesting conclusions for athletes who follow „Continuous Program” in Xert?

If you’re on a Continuous Program, there’s no need to periodize because there’s no end to the training program. However, you can still modify your Athlete Type interactively during the continuous program to manage your own periodization. Move to Time Triallist for example to get PYR training and change to Puncheur, for example, for more POL training.

Fixed that for you.

Perhaps the conclusion would be to expect similar results rather than “best”, since the study didn’t attempt to identify what’s best overall but what’s best between the programs tested.

I was just reading through the study again. One thing I noticed is that the runners in all four groups got a big rest week every four weeks…3 weeks on, 1 week with 30 - 40 % less training load. Seems to me to be a significant difference from Xert.

The other thing that occurs to me, and correct me if I’m wrong, is that the first period in Xert periodization has no time above TP, which is zone 3 in the study, No time in zone 3 means your pyramid is missing its cap.

One other thing… The study used TRIMP to quantify training load…in other words, heart rate, in order to keep the training loads constant between the groups so as to isolate Time In Zone. Considering that the differences found between the groups were rather small, couldn’t that be easily explained by ordinary vagaries in heart rate?

Watch our latest video to understand how rest weeks would work within Xert.

Some of our Endurance workouts do have some periods above TP but very little. 20 minute power is classified as Endurance but can have time spent above TP.

Wrt to using HR, it’s a bit hand wavy in terms of being very specific in quantifying training load but for this sort of study, it’s fine.