Not every session in your week carries the same weight, and the plan says which is which.
- A key session is the one the week is built around. If you only get two sessions done, these are the two to do.
- An optional session is there if the week goes well. Missing one is not a hole in your training, and your coach does not treat it as one.
- Everything else sits in between: worth doing, not worth wrecking your week for.
If a week is going badly, this is the order to protect. You do not need to ask — dropping an optional session changes nothing about how the week is judged.
Older sessions, written before this distinction existed, are all treated as ordinary rather than optional. Nothing was guessed retroactively.
Where this lives in the app: Plan