Owning the day also involves creating minimums, if today one awakes feeling off and sick or any other form of disease, what is the minimum that must be done to stay on track? Hit those minimums and rest for the day. The ideal scenario includes setting these minimums before one faces a lesser day, for otherwise the justifications for what it is a minimum. The mind plays victim to the tired impulses of the body, and discipline then is to correct it with these minimums.
Meditate.