The assimilation week: the easy week that builds progress
One week in four, the plan reduces volume by 30 to 40% while keeping the paces. It is not rest: it is the week where the body turns the previous three weeks of training into progress. Here is why it exists, what it contains, and when your AI coach brings it forward.
Last updated: 2026-09-19
Why the body needs to assimilate
Training does not make you progress: recovery after training does. Three weeks of rising load dig a fatigue debt; the fourth repays it and lets the adaptations appear.
Without this week, fatigue piles up, paces degrade and motivation with them. It is the classic mechanism of the runner who trains more and runs slower.
What it contains
The same number of sessions, but shorter: the long run is cut by a third, quality sessions keep their pace but lose one or two blocks, easy runs are shortened. Paces never drop: it is volume that comes down.
The coach sends it to the watch like any other week. The difference shows in the step durations, not in the targets.
When the coach brings it forward
Three signals, read in your Garmin data and your weekly answer: an ACWR above 1.3 two weeks running, a feeling of 2 or less two weeks running, or a quality session missed through fatigue.
- Volume −30 to −40%, paces unchanged.
- One week in four, or earlier if the signals require it.
- Never skipped, even when form is good.
In those cases the assimilation week is brought forward by one or two weeks and the plan resets behind it. You lose nothing: an easy week taken in time avoids two weeks of forced stop.
Frequently asked questions
Can I skip the assimilation week if I feel good?
No. It is precisely when you feel good that it builds the most progress. Skipping it pushes the fatigue onto the next block.
Should intensity be reduced too?
No, only volume. A 2 × 10-minute threshold session instead of 3 × 10 keeps the stimulus without digging fatigue.
Can the coach move it for a tune-up race?
Yes: a preparation race takes the place of a quality session, and the assimilation week goes right after.
Let your assistant write your sessions
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