Our brain consumes all this energy because it takes on the responsibility for a lot of the activity in our body. Apart from monitoring our heart rate, body temperature, telling us when to get food and sleep, it also spends energy in helping us decide whether to wear the blue sock or the black one, whether to eat the cereal with chocolate or with raisins, whether to listen to John Mayer or Coldplay, and so on. 

This is where planning and habits come in. 

The first time you ride a bicycle, you are consciously paying attention to keeping your balance, ensuring you brake at the right times, pedal at the right speed, keep an eye out for vehicles and people on the road. All so that you don't fall off and hurt yourself. Because the brain hates it when our body gets hurt. The brain hates it because a hurt body cannot find food which will then result in death, but that's another story.

However, if you have been biking long enough, you will find it easy to listen to a podcast or talk on the phone, or even text, while you are riding the bicycle, without ever having to slow down from your natural speed. This is because the brain has identified major patterns in riding a bicycle on the road and frees up computing resources to process other things (like a conversation or the content of a podcast) and only draws attention away when it really needs more resources. This happens when it encounters something out of pattern - like a kid jumping out in front of you unexpectedly, or a car skipping a red light and cutting you off.

This is not just with riding a bicycle, of course. It happens with work, with relationships, with travel, with the food we eat, with the conversations we have, with the shows we watch, everything.

In the field of computer animation, this process is called tweening. You can define two states in an animated scene and ask the computer to fill in the frames in between, resulting in a smooth animation, without having to draw every single frame yourself. And this works because of simple laws of Physics that are programmed in. It is the equivalent of positioning yourself to receive a football that a teammate passes to you. How do you know where to position yourself to receive it before the ball actually gets there? Laws of Physics. If it is hit with a certain force and a certain angle, you can anticipate where it will end up in a few seconds and position yourself there to receive it. Tweening works the same way.

Our brains work the same way too. If you're watching the tenth episode of Castle or reading the tenth Agatha Christie book, you don't really have to pay full attention to what you're doing. Even if you catch two distinct states, you can pretty much make up what happened in between with remarkable accuracy. Because our brains are good at processing patterns, and tweening, in general.

This is why, if you look back upon the year that passed, the days seem to merge with one another and you will only be able to recall days that were distinct and deviated from the norm - like your anniversary, or a new city you took a trip to - while the rest of it seems to be a blur that went by quickly.

This is the science behind habits and planning and how they can boost creativity and productivity. They simply manage to free up our brain's computing resources to focus on other things. It is the equivalent of having a better operating system in your computer.

While we have limited processing power (brain size and cranial capacity), we can optimize what we have to do more. After all, this is the insight that has been driving Amazon's tremendous growth in the recent years through its cloud computing division (AWS), where computer programs are scheduled such that every server is utilized to the maximum. This is the future of cars once self driving cars take over - cars will not sit idle in parking spaces, but will serve those in need at the time instead.

Habits take simple decisions out of the way (like focusing on balancing the bike and stepping on the pedal) and put them on autopilot and free up resources for other things (making a call, listening to a podcast).

And that is how they make you more productive and more creative.