Any guesses?

It is stamina.

The ability to sustain the prolonged physical or mental effort.

Modern professionals need to engage their mental faculties for a long time. Modern work requires you to sit for long hours so physical stamina is also a must.

Without the stamina, you will not be able to stay focused and have the required energy to think through complex situations.

Most of us pay more attention to learning and networking than focus on building stamina. But I’d suggest making stamina building a priority over anything else.

This is even more important for a professional writer. For a professional writer, the writing does not stop at putting words on paper. She needs to go through several rounds of rewriting. In case of non-fiction be ready to do a fair bit of research, and include that in what you write. It will definitely test your stamina on the edges.

How to Build Stamina

Start with the basics and focus on core i.e. sleep, food and movement.

Sleep for 7-8 hours per night, eat greens and fruits and include some form of movement in your daily routine.

Work at a fixed time and place.

By doing this you reduce variables and cognitive load. This way your brain will function at a higher capacity than if you work at random times or places.

Put yourself under situations where your mental and physical abilities are tested.

Like giving yourself deadlines when there are done and then meet those deadlines. Once in a while test yourself by working non-stop because you will not have perfect conditions always. You can also work in cycles.

Learn to be efficient at all times.

For one week or a month, work from 7 am to 2 pm and give your best. Next month, do noon to 7 pm cycle. And then for a month, do a 4 to 11 pm cycle. This is your self created Navy seal training for your mind and body.

Once done, go back to a routine, when you naturally work the best and one that is practical. But this practice will make you confident and allow you to take up any situations without much hassle and still give your best.

Pace yourself.

If you need to work on something big, instead of killing it in a day, plan to do it in a month or a year, one day at a time.

Take breaks.

Not the kind where you watch video while eating but where you engage in something that frees your mind, like spending time with friends or family. This will give your mind a much-desired break and make it ready for the next burst of activity.

Last but not least, make your environment work for you.

Choose a work environment that does not suck the energy out of you. Open plan offices are great so are coffee shops but the noise can be a big distraction so when working at such places either use ambient music or plan your work there at times when the footfalls are usually low like in the mornings and during the middle of the week.

Is there something else that you do or use to enhance your stamina?