4 Ways Entrepreneurs Can Work Less for More Success "Work" may be the mantra of high-achieving entrepreneurs, but "rest" is what will really propel you to new efficiency heights.

The struggle to succeed in business is often likened to the training required for an IronMan triathalon. Athletes and entrepreneurs alike are high achievers -- exemplars of grit and determination. But, just as marathoners include rest days in their training programs so their muscles can recover and become stronger, so should entrepreneurs "work smarter" by working less.

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In their new book Peak Performance: Elevate Your Game, Avoid Burnout, and Thrive with the New Science of Success, Steve Magness, a professional running coach, and Brad Stulberg, an expert in the science of human performance, assert that rest is crucial to forward progress across various endeavors -- especially those of the business variety. You won't grow your business by running on fumes all the time. Instead, refilling your tank is the ticket, the authors argue. It's part of the work.

Of course that's easier said than done in a culture that rewards those who burn the midnight oil. Couple that with such inner drivers as ambition, guilt and a desire to prove our worth, and it makes sense why we sometimes feel the need to work excessively.

In fact, this tendency is one of the biggest mistakes entrepreneurs make. A study by John Pencavel of Stanford University linked work hours and productivity. He found that output for an individual drops after a 50-hour work week. "I really don't need much sleep," claims many a high achiever. But that's simply not true. And the Stanford study wasn't alone in saying this: The Wall Street Journal reported other research saying that 98 percent of people suffer diminishing performance on six hours of sleep or less a night.

The answer isn't to forego work for sleep or vice versa. It's to make sure you have the right amount of time for both. By learning to work smarter, you can become a better leader -- and a healthier one, too. Here are four ways to work less and achieve more.

1. Jump-start the multiplier effect through delegation.

If you're anything like me, you often have to resist the urge to bootstrap everything yourself. You've built your startup from scratch, invested your personal wealth and assumed ultimate accountability. Who could blame you for wanting to hold on to that?

You may be able to complete certain tasks more efficiently, but you cannot do everything better, faster and smarter. Passing on tasks empowers others, gives you new perspectives and brings new skills to the table because of the broader team that's been engaged. That's when the "multiplier effect" kicks in.

The multiplier effect is "you" times the number of people whom you effectively coach and empower, to spur greater output. In short, there's no need to work 24/7, because you have capable people around who have the tools and resources needed to power your company.

Still need convincing? A Gallup poll found that of 143 CEOs surveyed, those with high delegator ability showed an average three-year growth rate of 1,751 percent, which was 112 percentage points greater than that of CEOs with low levels of delegator talent. Additionally, in one particular year studied, 2013, CEOs who delegated enjoyed one-third more revenue than those who didn't and saw an average $8 million versus $6 million more in revenue.

2. Plan your work; work your plan.

Years ago, I proudly showed my boss a list of goals I was working on, and his response has stuck with me since. He looked at my long list and told me to pick three goals and do all I could do to accomplish them -- because they mattered more than the others. His message was clear: I needed to focus my work to deliver where it counted.

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Rather than spread yourself thin, identify the greatest value that you can bring to your company. It could be implementing strategy, building relationships or securing resources -- but it shouldn't be all three at once. According to neuroscientist Earl Miller, "People can't multitask very well, and when people say they can, they're deluding themselves."

Next, determine the greatest value that you can bring to the company today. This will constantly change. For example, you may need to attract new clients, but several months from now, you may need to focus on recruiting new staff instead. The future of your business depends upon your ability to look through the turn, as I often say. Examine market trends, the competition and how technology is impacting your industry.

By looking ahead, you can pinpoint exactly what you should focus on next month, next quarter or next year.

3. Introduce "no" into your vocabulary.

As a leader, the opportunities come flooding in -- from volunteering on local boards to attending social events to writing a book. Saying "no" more often than "yes" is vital to preserving the time you need to devote to your business.

Steve Jobs was a skilled practitioner at the art of saying "no." He's quoted as having said: "I'm actually as proud of the things we haven't done as the things I have done. Innovation is saying 'no' to 1,000 things."

Still, saying no is hard. We hate to disappoint bosses, colleagues or friends. Research shows we're hardwired to please, but doing so can backfire because it leads to overcommitment.

To prevent becoming a yes man (or woman), compile a list of criteria to use to vet opportunities. Tie each opportunity back to the value that you bring to your company today. For instance, if you're focused on hiring right now, consider whether the opportunity before you helps raise visibility for your company.

You don't have to close the doors on opportunities forever. Rather than saying "no" outright, say "not now." Next time people approach you with an amazing opportunity you don't have capacity for, tell them you can't commit right now but you'd like to be reconsidered in the future.

4. Work to live -- don't live to work.

Workfront's 2015 State of Enterprise Work report found that Americans spend only 45 percent of their working hours doing the primary duties of their job. The rest of the time is spent on checking emails, nonessential tasks and meetings. The most successful people I know, however, schedule "me time," too. They understand that this provides a buffer that will never be captured unless it's planned.

Twice a week, block off 30 minutes to an hour on your calendar. Set aside email and your phone. Use the time to focus on a complex problem, develop a new strategy or reflect on a situation you could have handled better. Your personal life is also a priority. Appointments, family events and vacations should be on your calendar well in advance so you can plan around them.

According to Dov Frohman, former vice president of Intel, "Every leader should routinely keep a substantial portion of his or her time -- I would say as much as 50 percent -- unscheduled. Only when you have substantial 'slop' in your schedule . . . will you have the space to reflect on what you are doing, learn from experience and recover from your inevitable mistakes."

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"Work" may be the mantra of high-achieving entrepreneurs, but "rest" is what will really propel you to new efficiency heights. You can do less and achieve more.