One of the best ways you can regain lost hours is to learn how to manage email. Is it possible that you don't get enough time for lunch? What is it that makes you late for every meeting? What is it about your daily to-do list that only a handful of items are completed each day? You should take a hard look at how much of your time you spend on email each day.
You spend 5 hours a day on email if you get 100 emails a day, which is a common occurrence for office workers, particularly those in managerial positions. This is half or more of the time you spend on email each day for an average 8-10 hour workday. Learn email management and you will see your productivity levels rise.
Set aside a time each day to respond to and read emails. It's important to stick with it. It is common for people to have one email session per day, one at lunch and one at night. Consider a short session after lunch if your work is very time-sensitive.
Before you send any replies, scan all emails. This is not an easy task, but it is crucial. You can read them all and take notes about the most important things as you go. Once you have read them all and taken notes, you can use those notes to quickly reply to the most important points.