I usually sleep 4-5 hours per night, and the less I sleep the more I do. Don't be surprised. It is all about the quality of your activities and the respect you have for your body and your mind.
I am a big fan of lazy working which means do more with less but make sure you conclude your activities just when needed and not before. In computer science, we have this beautiful concept of Lazy evaluation, also known as "call by need" which delays the evaluation of an expression until its value is actually required. The intuition is very simple you start an activity very very early, but you don't conclude it immediately. No, you defer it until you are forced to conclude it by a real need.
Let me make a toy example to clarify. Suppose you need to compute 2+3, you write the sum but you don't carry out the summation. Instead, you defer it. And you keep deferring until you need to consume that result for another operation. And so on and so forth. It's a very simple principle but it is powerful. Because it allows to do more with less. Why? because you can start multiple activities, and you keep deferring them until you really need to consume their results as input to new activities.
The magical aspect is that you can carry out many activities in parallel. If you are good in managing your time, you will start to observe a mutual boosting effect where you reduce the time needed to conclude one single activity because you have all the other pending and waiting on-hold.
In a sense, this is similar to a runner who is not just running. No, she trains her body taking care of different muscles of her body in parallel starting to improve each muscle, then stopping that particular activity and starting a new one, deferring the conclusion until there is a real need.
So next time someone will ask you: "Are you focused? Are you carrying out your assigned activity?" you may answer: "No, I am a lazy worker. I do more with less"