If you start your day at work already exhausted, you're not alone.
According to The General Social Survey of 2016, nearly 50 percent of people say they are "often or always exhausted due to work," which is a 32 percent increase from 20 years ago, reports Harvard Business Review.
Sixty-three percent of people say they have "high levels of stress at work, with extreme fatigue," according to a 2012 CompPsych survey, writes USA Today. Thirty-six percent "just work harder" to cope.
"People are so exhausted because they are always on," Steve Magness, co-author of "Peak Performance," tells CNBC Make It.
The problem is, no one gets better at their job just by pushing harder and harder, as New York magazine points out in an interview with Magness and his co-author, Brad Stulberg.
Magness, who coaches professional runners, began researching "Peak Performance" to find out how driven individuals can get ahead in their fields, without burning out. What he found is that while stress is necessary for growth and performance, so is recovery. People need to "let their minds bounce back and rest so that they feel rejuvenated," he says.
Here are five simple strategies you can use every day to be more productive without losing your stamina.
1.Take a break, a REAL one
"Sitting down in front of the TV while you are on your phone checking Twitter, that doesn't really help," he tells Make It CNBC. While you might think it's rest, "your mind was still active and engaged and all of that stuff, so that is why you get that mental exhaustion, that 'blah' feeling."
Instead, spend a little time with friends. According to Magness, "social recovery" allows for decompression and creates a "transition phase to go from high stress to allowing your body to rest," he tells New York magazine.
2. Accept stress and use it
In the book, Magness and Stulberg describe their formula to success as "stress + rest = growth."
So some stress is good. "Obviously you're not going to get better at whatever it is you are trying to get better at unless you really work at it," he says.
But view stress as a stimulus or a challenge instead of problem. For Magness, the right mindset is: "I'm feeling a little bit uncomfortable, but that is good because that is a signal my body is getting ready to go to battle," he says.
3. Improve your sleep
When people prioritize work over sleep, they gain more hours, but they inevitably get fewer things done.
"Your productivity, your cognitive abilities, your creativity, they all plummet," without sleep, he says. "So while you have more time, you just become less productive and over time your body just goes into this physical, mental, psychological rut because it can't get back to 100 percent."
To get more quantity and better quality sleep, keep your phone and your computer out of your bedroom, suggests Magness.
4. Split up your work day
"Plan in some breaks," he says. "They might just be like five minute breaks, where you get up, you go walk around, you stop sitting at your desk." The important thing is not grinding away for eight (or more) hours straight.
A short 10 minute walk will boost your productivity and creativity, he says.
5. Don't let your career be your identity
It's a problem Magness sees in his athletes — running becomes a defining quality. "It becomes solely who they are, and then if they don't do well or if they fail, it is an attack on their ego and their self," he says.
So think of work as just something you do. "If you shift that mindset," explains Magness, "it just makes it where you can be sustainable for longer."
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