More than 1.6 billion Muslims around the world fast for the Holy Month of Ramadan, refraining from consuming any food and drink from sun-up to sun-down. This annual month of fasting is one of the Five Pillars of Islam, and it's intended as a time of reflection, prayer and giving.

But without food or drink, it's easy for focus and energy to slip, something that can prove challenging for Muslims in corporate office environments and entrepreneurship alike. With a few smart changes and strategic adaptations to your behaviors and priorities, you can still get plenty of productive work in, whether you're working in an office setting or on your own as an entrepreneur.

Here are some tips for making the most of your work-day while fasting.

Plan Your Days In Advance, With Intention

Keeping your mind occupied can sometimes be a challenge during Ramadan, when hunger can seep in as a distraction. By carefully planning your days and deciding, ahead of time, what you'll focus your time and attention on, you'll be better able to keep your momentum going.

When planning your days, try to schedule meetings, calls and other interpersonal interactions that require high energy in the mornings. Put high-priority tasks and items first, ensuring you make progress on the most pressing items, and leave less pressing or mentally intensive tasks for later on, when your energy and focus may wane.

Work When Your Energy Is Highest

Your energy will likely be highest just after eating the morning and evening meals. If possible, plan to do the bulk of your mentally or physically intensive work just after eating, when your mind and body are at their sharpest. You may find that staying up after you eat your morning meal--instead of going back to sleep--will allow you to more easily complete tasks without the distraction of incoming messages and distractions at that hour, too.

You can use scheduling tools like Boomerang for Gmail, to ensure that messages you compose during these high-energy sprints are sent out at a more typical business hours to accommodate your your clients, partners and customers' expectations.

Swap Meetings For Video Chat and Calls

Travel, commuting and walking can drain your energy. Whenever possible, look for opportunities to shift in-person meetings to phone calls or video chats. Often times, you can get just as much done, without having to use valuable energy to physically get yourself to a different location to meet.

For many people--even those not fasting--this will be a welcome change, as it saves them travel and movement time too. This extra time can be used for other activities and tasks, allowing you to make even more progress on your goals and to-do list.

Embrace Afternoon Naps

The afternoon and early evening can be the toughest times for energetic work during Ramadan, so don't be afraid to take a nap to regain some energy and pass the time. This will be particularly helpful if you've opted to stay awake after the morning meal. An afternoon nap will allow you to re-charge, giving you a short burst of energy upon waking in the early evening.