When I feel overwhelmed with everything I need to get done, I remind myself of the power of three uninterrupted hours.

I am always less stressed when I have time alone to work and think — and I have learned that three focused hours drastically improves my mood.

This is true whether it is hundreds of emails that have piled up, or a big new project that needs to get started.

The scariest part for me is actually thinking about the volume of work before I’ve started, because it seems as though I won’t have enough time to get it all done. But once I actually dig in, it’s never as bad as I feared.

One hour is not enough to put a real dent in the work — It usually takes a little while for me to get into the task, especially if it’s a creative project. After two hours, productivity is often flowing, but stopping at that point would halt the momentum.

Three hours is the sweet spot for me to make significant progress and to create peace of mind.

I didn’t initially realize how important a three-hour block was — but after referencing the clock, I noticed a consistent pattern of being ready to stop at that point. And I recognized that the stress had melted away.

The key is ensuring the three hours are free of disruptions. This means locking myself away in a quiet area at work, or going to a coffee shop where nobody will bother me. I make sure to put my phone away to avoid unwanted interruptions. This type of atmosphere enables deep work — the ability to focus without distraction on a cognitively demanding task.

Now that I know how critical three consecutive hours are for my productivity and well-being, it is up to me to create that time. That often means blocking my calendar from calls or meetings, or postponing social commitments. After I have reduced my workload and stress levels, I am better able to truly be present with others.

If three hours seems like a lot, I remind myself that I’m awake for at least 16 hours each day. Spending less than 1/5 of that time making progress against my most important tasks is well worth it.

Maybe the power of three uninterrupted hours will work for you as well.

The next time you’re feeling overwhelmed, try devoting three straight hours to the work that is stressing you out most.

If you’re like me, you’ll emerge feeling clear-headed and accomplished. It’s amazing what three focused hours can do.

Andrew Merle writes about living well, including good habits for happiness, health, productivity, and success. Subscribe to his email list at andrewmerle.com.