Did you hear this? Jack LaLanne (search) is 90 years old. Ninety years old! This is the guy my mother used to exercise to when Eisenhower was president!

Before Richard Simmons and Jane Fonda, there was Jack — compelling a nation to get off its lazy butt and lift the dining room table ten times.

He still looks fantastic. Still exercises two hours a day. Still watches what he eats. They say he has the energy of a guy half his age. He looks like a guy half his age! And that makes me feel twice my age!

But you know something? I don't think it has anything to do with his exercise, or his fruit juicer. I think it has everything to do with his attitude.

I've talked to the guy. He's one of the most fun interviews I've ever had. You ever meet someone who just makes you feel good? Who makes you feel happy and seems to delight in the most trivial things? Jack's that guy.

He never complains. Never sulks. Never says a bad word about anybody or to anybody.

He thinks like a young guy and with his wife of nearly 50 years, worships her like a young guy, even though now he's a pretty old guy.

Smiling. Laughing. Joking. Kidding. Eating right helps. Acting right helps more.

So, happy birthday, Jack. I'd salute you with a yodel, but better reach for the carrot juice in case you're checking up on me!

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Neil Cavuto serves as senior vice president, anchor and managing editor for both FOX News Channel (FNC) and FOX Business Network (FBN). He is anchor of FNC's Your World with Cavuto - the number one rated cable news program for the 4 p.m. timeslot - as well as the FNC Saturday show Cavuto on Business. He also hosts Cavuto on FBN weeknights at 8 p.m. In addition to anchoring daily programs and breaking news specials on FNC and FBN, Cavuto oversees business news content for both networks and FNC's weekend business shows, including Bulls & Bears, Forbes on Fox, and Cashin' In. Click here for more on Neil Cavuto.