At present I’m working long hours and have found a way of dealing with this (read on if you are vaguely interested).
Now I could try to give you lots of advice on how to prioratise, delegate, etc however I’m not going there.
The one thing I would recommend is to work in “waves”.
The reality of being senior is that no matter how smart you work most of your working day will be taken up with meetings and you will often complete ‘actual work’ (emails, papers, etc) in the evening.
However if you keep doing 12-14 hour days you will eventually burn out. Fact.
So why not adopt a Wave work pattern?
Dumbing it down for the majority of the time you will work long days however when you can steal time back e.g. go home early or work from home. Do It.
My other piece of advice is to decouple yourself from tech at least once a week. i.e. Sunday becomes your (work) trough day.
I no longer touch digital (phone, tablet, computer) on a Sunday and as a result feel so much better for it.
Waves are awesome.