My son-in-law is fond of saying there are two kinds of people we encounter: Energy givers and energy drainers.

Some people are so vibrant and so passionate about life. That upbeat attitude is contagious. When we're around someone like that, we, too, find our own mood elevates.

I interviewed a fascinating guy this week whose energy and enthusiasm for life had me smiling.

Ed thrives on being outdoors and studying nature. Passionate about fishing, he takes his boat out every day. He's also an avid kayaker. But he does much more than paddle.

When he kayaks, Ed takes along a pair of clippers to trim mangroves that may get in the way of other kayakers.

By now you're probably thinking, well, all that is fine. But what's so exceptional about someone like that? Plenty of people like to fish and kayak.

What I didn't tell you upfront about Ed is his age. In October, he will celebrate his 95th birthday. He's still agile and still awed by the beauty of life.

He has made some concessions to age. He no longer travels alone for months at a time to foreign countries and he says he does a bit more sitting than he used to. But his stamina is still amazing.

When I asked him how he manages to stay in shape, he pointed to the big ladder leaning against his house.

"To stay in shape, I walk at least a mile every day and I climb up and down that ladder about five times in a row. Climbing is great exercise," he says.

I should tell you that he stands with straight posture, being "careful not to hunch over like an old man." He carries a cane "just in case he needs it for balance," but I didn't see any sign of a problem during the time I spent with him.

As a matter of fact, he showed me how he can pull his kayak by himself to the water behind his home.

When he goes out each day in his boat or kayak, he usually includes a visit to the mangrove tunnel a mile from his house. While there, he trims away any low branches and makes sure the three-mile mangrove trail is passable.

He has a special interest in what has been named after him – the Woolverton Trail – because he was the one who discovered it 25 years ago. Actually, it wasn't a "trail" at that time. It was a series of ditches dug through thick mangroves for mosquito control.

Working alone, day after day, month after month, Ed cut back the heavy growth blocking the openings, creating one long maze of mangroves for kayakers who love the pristine beauty of unspoiled nature.

Ever since, the mangroves have become a tourist attraction. Most people love the solitude and tranquility of the Woolverton Trail but few know the story of the man who created it.

I did a story on Ed a few years ago. He's one of those people you never forget. So I dropped in last week to visit. I planned to stay about an hour but found myself reluctant to leave.

Ed's a great storyteller and he can converse about everything from world news to his newest recipe.

One of his favorite topics is nature. He is totally fascinated about bugs, butterflies and every living thing. When I was there he just finished watching a video called, "Ants: Little Creatures Who Run The World."

What I enjoy best about Ed is his little boy enthusiasm for all of life. At 94, he's still in love with life and awed at what he calls "the wonder of it all."

It's no wonder that people of all ages and backgrounds beat a path to his door, anxious to spend time with him.

Oh, I forgot to tell you another reason why he has so many visitors: As a member of an international hospitality exchange organization, he invites other members to visit his Florida home. He recently had 37 visitors from 13 different countries. While most come expecting to spend two nights, some are invited to stay for weeks or even months and his favorite people come back year after year.

That, he says, is in payment for the many people across the globe who opened their homes to him during his many international trips.

I must say when I left Ed's house I was smiling even more than usual and felt filled with energy.

That's the way it is with energy givers like Ed. We feed off their vitality.

On the other hand, we've all encountered those energy-drainers who seem to suck the life out of us. I know a few constant complainers who filled every conversation with a litany of criticism and complaints.

I have a theory that if I remain upbeat around them, maybe I can uplift their mood. It often works the other way – I find myself pulled down. And I almost feel that "it's not right" to be so upbeat around someone so morose.

I talked with a renowned psychiatrist who shared what he tells some of his depressed clients. "I tell them to get away from themselves by focusing their attention on what they can do for others," he said. "And I tell them to hang around positive people."

In other words, he tells them to seek out energy givers like Ed.

Are you an energy giver or an energy drainer?