The taper: the two to three weeks that decide your time
The taper reduces volume before a race so you arrive fresh without losing fitness. Too short, you arrive tired; too long, you arrive rusty. Here are the durations and reductions your AI coach applies by distance, and what it keeps in the final week.
Last updated: 2026-09-19
Duration and reduction by distance
Marathon: three weeks, volume cut by 20%, then 40%, then 60% in the last week. Half: two weeks, 30% then 50%. 10K and 5K: ten days, with a last short quality session five days out.
In every case intensity is kept: quality sessions keep their paces but lose repeats. That is the rule that separates a taper from mere rest.
The final week
Three sessions at most: an easy run with a few strides, a short session at race pace to remind the legs, and 20 easy minutes the day before or two days before. Nothing new: no shoes, no route, no food.
The plan sends these sessions to the watch with the "Race" session already scheduled on the day, carrying the pace range per segment.
Misleading sensations
During the taper, many runners feel heavy, restless, convinced they have lost fitness. It is normal: the body stores glycogen and repairs. The legs come back in the last 48 hours.
- Marathon: 3 weeks, −20 / −40 / −60%.
- Half: 2 weeks, −30 / −50%.
- 10K and 5K: 10 days.
The coach knows it and does not change the plan on a taper feeling. The weekly review shows the load coming down: the sign that everything is going as planned.
Frequently asked questions
Should you run the day before a race?
20 very easy minutes, yes, to loosen up. Or nothing at all if you prefer: both work, the key is doing nothing new.
Can I do a tune-up race during the taper?
Not in the last ten days of a marathon. A 10K three weeks out, in place of the last threshold session, is classic and useful.
Why do I feel bad during the taper?
Because the body is repairing and storing. Heavy sensations, restless sleep and small phantom aches are usual. They vanish at the start.
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