Move your body.

The toughest part about a day full of meetings is that you sit a lot. Especially if the meetings are happening in different places and you commute to them - unlike being at one campus where you can at least do some of them standing up or walking.

It is the sitting - at meetings and during commutes - that screws up a lot of things in the body. From postural issues to numbness to reduced oxygen flow et al, with no way for the body to replenish lost energy.

The best thing you can do for yourself at the end of such a day is not the drink at the hotel bar, but the workout you can squeeze in before dinner.

Even if it is for 30 mins, move your body and do it well.

You will literally feel energy surging back into you. Your body will feel lighter and limber, and you will have a real chance at enjoying the evening instead of having to power through a wall of exhaustion.