I’ll assume that by “objective” you’re meaning an extended event of multiple hours and even days. You will be in a calorie deficit after this and training and recovery will be impacted. Eat your normal healthy diet. Don’t eat reduced carbs during this time thinking that you need more fat adaptation. You’ve just completed a major fat adaptation training session and need to restore both macro and micro nutrients. Don’t try to pack in calories artificially by over eating. Better to eat small and more frequent meals. Recharging glycogen stores can take days if you’ve really drained your tank.
I don’t know of any magic way to speed the process up.
Scott