Busy professionals often neglect their health; I know that with all of my travel and consulting, I have sometimes found it difficult to eat right or exercise. But I also know that when I let my health slide, my efficiency declines. I have less energy and focus either for my business or for the things I love to do, like cycling through New England or running with my wife.

YPO Canada member John DeHart helps others address this challenge every day. In fact, he has dedicated his career to one purpose: being a change agent to help people be happier and healthier in how they pursue life. Guided by this purpose, he has co-founded two highly successful healthcare companies: Nurse Next Door, a 150-location home care company focused on helping seniors age at home and find daily happiness as they age, and his latest startup, LIVE WELL Exercise Clinic, a soon to be 20-location company that helps boomers with chronic disease create lasting lifestyle change to live longer, healthier lives.

John, also a longtime athlete, knows the importance of applying those same principles in his own life. With that in mind, he spends a lot of time researching and testing what it takes to live happier and healthier. Here are the principles he has found to work best for himself and the customers of his companies.

1. Happiness happens by design.

"At Nurse Next Door, we spent years studying the science of happiness (also known as positive psychology), and found that we actually have full control over 40% of our own happiness," DeHart explains. "A key finding suggested that the frequency of positive experiences is much more important than intensity of positive experiences. People think happiness comes from big things--a prestigious award, winning the lottery, an exotic trip or a big promotion--but it can come from little things, too." He recommends identifying simple, daily things you enjoy: hugging a loved one, playing with your children, going for a run, or enjoying a quiet cup of coffee. To increase your overall happiness, focus on making good experiences, even small ones, happen every day.

2. You are the sum of your habits.

Many of the clients at LIVE WELL Exercise Clinic have serious health problems; they struggle with obesity, diabetes, and other issues. They may never have exercised and may need to completely overhaul their lifestyle if they want to survive. DeHart saw that for many, this seemed like an impossible challenge. "The problem is that habits are hard to form, and new ones are even harder to keep. Most bad habits have immediate gratification, and the downside is long term but not immediately noticeable. Good habits don't usually have a short-term upside. That's why bad habits are so much easier and more attractive to adopt." His company's solution? Focus on the habit first and the results later. Instead of thinking about the results you want, dedicate your attention to just creating good behaviors with small steps.

3. Make one change at a time.

Because they want big results, many people think they need to "go big or go home" in lifestyle change. DeHart advises doing the exact opposite: "Like boosting your happiness, think small and often. Start with something small and nail it." He admits that when he sets a big health goal or tries to implement multiple changes at once, he has failed. So instead, he has learned to select a few clear goals and to implement a few daily habits at a time. These eventually add up to big results. If you start to feel impatient because the future is not arriving fast enough, look backward and remind yourself how far you have come.

4. Pinpoint the "why" for what you do.

Hardly anybody likes to be uncomfortable, but it is possible to get comfortable being uncomfortable if you believe firmly in what you are doing. "If you try to motivate yourself with an unclear or inaccurate reason," he insists, "your healthy pursuits will feel like chores." In contrast, finding the right why creates clarity, a sense of what is truly important, and the determination to follow through. He gives a personal example: "The men in my family have all died at an early age of diseases caused by poor lifestyle. I am determined that isn't going to be me. I will do whatever it takes to break this trend. I will do whatever it takes to still be out running my girls when they grow up." Purpose fuels behavior and motivates lasting change.

5. Win the morning to win the day.

Again, DeHart applies his advice to himself first: "From research that shows people who rise earlier accomplish more in life, to the life experience of so many successful leaders, this one is a no-brainer. I do my best work in the morning, so I have always started work at 4:15 a.m., which gives me a solid quiet hour before my kids wake up." He considers this routine a "boot up sequence" for the day and uses it to execute habits like meditation, stretching, and eating a healthy breakfast. Finding your right morning routine will leave you feeling mentally stronger, more balanced and ready to take on anything that comes your way.

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