Time management: a hallmark interview question. A skill whose importance has been drilled into us by parents, teachers, and bosses. A seeming non-negotiable for a career (and life) well-lived. 

But what if we got it all wrong?

The issue is we focus too much on time management and not enough on energy management. The former relies on frequent, ad hoc planning of an irregular, finite resource (time). The latter relies on rituals

And it's the latter that works for the super successful. 

Tim Cook, CEO of Apple, knows this. Up at 3:45 a.m., he uses the early hours for pure, uninterrupted work, before heading to the gym at 5 a.m.

Locking in this energy ritual means that, by the time the rest of the world wakes up, Cook's not only a full half-day ahead, but also physically and mentally operating at a more optimal state.

Here's how you can similarly hack your life -- backed by science.

It's called a biological clock for a reason

Time is a limited resource. But energy is a renewable one. Knowing exactly when to tap into your energy reserves and when to step back means more bang for your energy buck. 

Our bodies go through something called ultradian rhythms, which are 90- to 120- minute cycles during which our bodies move from a state of high to low energy.

During these periods of low energy, our bodies crave recovery: we yawn, feel restless, and get hungry. This means that working for more than two consecutive hours is a recipe for failing productivity. 

Energy ritual: After 1.5 to 2 hours of work, leave your desk. Go for a 10-minute walk, eat a banana, or listen to your favorite song. This downtime is just what your brain needs to prepare for another two hours of solid work. 

Pro tip: Don't check your phone.

Death by Multitasking

Your life is the sum total of what you pay attention to -- and paying attention is energy-heavy. But because the modern workplace reveres multitasking, seeing it as the path to productivity, it may feel like the more things you pay attention to, the better. "Look at me! I'm multitasking and getting work done!" 

We need to rethink this

According to the cognitive load theory (CLT), we use our limited-capacity working memories when we attend to new stimuli. This means that when we work on too many problems simultaneously, there's even less to go around. We end up feeling anxious, stressed, and mentally depleted.

Simply put, the more selective we are with what we pay attention to, the more leftover energy we have to dedicate to meaningful causes. 

Energy ritual: Section off one hour every morning for an electronics-free existence. Use this time to exercise, read, meditate, or plan your day.

Pro tip: Waking up to a phone alarm means you're more likely to start checking your notifications before you're even out of bed. Invest in an old-fashioned alarm clock.

Dopamine-Management

Whichever way you slice it, time management is still important. The trick is to manage it in such a way so as to create moments of value. 

Instead of rigid back-to-back commitments, accentuate your day with dopamine triggering moments. Dopamine closely links with reward centers in your brain and is involved in everything from memory and motivation to mood and attention. 

Connecting with close others, buying yourself flowers, or trying out a new place for lunch are all ways of injecting some joie de vivre into your day. You'll give yourself that energy kick you need to tackle the next challenge in your day.

Energy ritual: Feeling irritable or overwhelmed? Text someone close to you and tell them you appreciate them.

Pro tip: Make it a handwritten note.