If you want to build one sustainable businesslong hours are the norm. It's not just in the early days of business. I've been at it for over ten years and the ambition to grow my CPG startup is as strong as ever, which means that, after all this time, 16-hour days are nothing extraordinary.

The reason? Back-to-back meetings with investors, intense work sprints, firefighting and more, these are all in addition to daily tasks and responsibilities.

Popular wisdom says that most people max out at about six productive hours a day. But as a CEO, I can't afford to spend the remaining 10 hours in zombie mode. I pride myself on putting 100% into everything I do – and growing my business it depends on her. While 16-hour days certainly test that ambition, I make the most of every minute thanks to three practices I've developed over the years.

Related: Employees are burning out—and the culprit isn't who you think

1. Work planning

The main difference between 16-hour days early in your entrepreneurial journey and 16-hour days when your business is well established is that, in the latter case, you generally know when and why the days are coming. long. This allows you to prepare accordingly.

Every Friday I prepare my assignments for the coming week. This includes both regular jobs and anything unusual. Basically, this means treating 16-hour work days like any other work day.

While it's obvious to me, it's a mistake I see many others make – they don't plan or schedule for the “second shift,” believing that any and all work beyond the usual eight hours is productive. Not only is it not true, but it amazes me that people are willing to do more work, with less effectiveness. If you have to sacrifice rest and family time for work, you should certainly try to handle the workload as efficiently as possible. This means treating it like any other job.

2. Get enough sleep

Seven hours a night is non-negotiable. While 16-hour days do happen occasionally, 18-hour days are out of the question. I can't be productive or sharp if I don't get enough sleep. I used to think I could, but, in retrospect, I see I was mistaking participation for productivity.

The extra hours of work you earn at the cost of sleep is like going to a loan shark – after instant profits, you'll pay off your debt with insane interest.

However, don't focus on the number. While seven hours is a sweet spot for me, it may not necessarily work for you. In case you haven't already, the onus is on you to determine your optimal sleep schedule. Once you find it, follow it diligently and although it may be difficult at first, your body will adapt to the routine.

3. Keeping energy up through physical activity

Surviving 16-hour workdays isn't just about the mental side—it's also a physical challenge, and one that you need to meet with the same amount of preparation as anything else. My routine may sound unconventional, but it keeps me operating at peak efficiency. I try to keep things simple: one meal a day, intense HIIT (high intensity interval training) training – often in the middle of the day – and always taking a cold shower.

These practices are not just random habits. They have been carefully curated over the course of several years as they have proven their worth in ensuring my productivity remains at its peak. Noon intensive Drillsin particular, are a game changer. They inject a burst of energy that carries me through the toughest parts of my workday. And cold showers? They are my secret weapon for staying sharp and focused.

It is not about creating a complicated system. It's about finding what works and sticking to it religiously. Some entrepreneurs engage in elaborate fitness plans or extreme diets. I'm not interested in that. My approach is simple: keep moving, stay disciplined and listen to your body.

The result? A consistent one energy level that allows me to face those long days without burning up. When you run a startup, it's worth its weight in gold.

Perhaps the greatest added value of such routines is that they eliminate the need for additional decision making. Even the most mundane decisions – what should I eat? What should I wear? Should I go to the gym? It takes a lot out of you. Eliminating them from your daily itinerary frees you up to focus on value-added activities.

Related: How to maximize every hour of your day for unstoppable productivity

Putting it all together

This systematic approach has allowed me to avoid burnout and always bring my A game, whether it's an early morning team or a late night investor call.

All of the above are combined with other productivity practices, such as diary and care. However, these are more general and geared towards general productivity rather than surviving those long days.

Of course, life and business will inevitably throw a wrench in the works. Business trips and unpredictable events can disrupt even the most carefully laid out routines and practices. That said, it's crucial to recognize these as the exceptions they are and do your best to maintain — or return to — the routine as soon as possible.