What a missed week costs, and what to do with the next one

By Raph · October 19, 2026

The week went sideways. A work trip, a sick kid, a cold you are still carrying. You ran once, or not at all, and now you are looking at a plan that expects more and wondering how much you lost.

A missed week costs you very little. What costs you is the next two weeks, when you try to pay it back.

Coaches plan for the week that goes sideways

Anne Tisdell, a CTS coach, says on the KoopCast (episode 225) that her biggest lesson is that training does not have to be perfect. It needs enough volume, it needs to be consistent, and it needs as much race-specific work as you can fit. In a busy or stressful stretch she tells athletes to get the key sessions done however they fit, and about 90 percent of her athletes go through a stretch like that.

David Roche says the same thing from the other end of the sport. On Some Work, All Play (episode 320) he says that if you struggle to get out the door, 10 minutes counts and 5 minutes counts, and that even for Olympic-level athletes, coaching is mostly structuring consistency over years, not hero workouts. His example is the miler Josh Kerr, who says he just does not miss days.

How little holds what you built

A 2021 review by Barry Spiering and colleagues looked for the smallest dose of exercise that maintains performance. In general populations, endurance performance held for up to 15 weeks when training dropped to as few as two sessions a week, or when sessions were cut by a third to two thirds, down to 13 to 26 minutes, as long as the effort stayed up. The review covers holding fitness, not building it, and its authors say there is too little data on athletes to set a number for you.

What to do with the week you are in

• Run what you can. Ten minutes counts. A short run keeps the habit, and the habit is most of what training is.
• Cover the one session that matters. Pick the key run of the week, usually the long run or the workout, and fit it in however you can, as Tisdell does with her athletes. Let the rest be easy.
• Do not pay it back. Missed miles are not owed. Skip the make-up runs and the doubled-up workouts. The week you are in is the one to run, not the one you missed.
• Keep one run honest. If you feel fine, run a stretch at the effort of your normal harder runs. Easy running holds the base. A little effort holds the sharpness; in the review, effort was the variable that held fitness while frequency and duration fell.

Our guide to training load and recovery covers building load, rest and time off.

What Runsense does when life takes your week

Runsense's coach writes your whole plan itself, working back from your race date and sizing it to the fitness you have today. When your week changes, you tell it what happened and it reworks the plan and says what moved: a changed week moves your sessions, a few missed sessions adjust the next week or two, and a bigger event like an injury or a long absence revises the whole plan. You never have to sit down and rebuild the plan yourself.

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