The only definitive proof you'll need to assure yourself and your loved ones that age is just a number is Manny Ramirez's body of work.
Manny had an impressive 19-year MLB career. A .312 lifetime average, 555 career home runs, 2,574 hits and 1,831 RBIs ... the list goes on. He's also responsible for the greatest cutoff in MLB history and once high-fived an opposing fan while turning a double play in left field.
The infamous cutoff came in 2004 when Manny was playing left field for the Red Sox and somehow managed to lunge at a Johnny Damon throw coming in from center field:
As for that high-five: May 14, 2008. The Sox were visiting the Orioles at Camden Yards and Manny tracked a ball down in front of the left-center field wall. Then -- like an Olympic swimmer reversing course -- Manny used the wall to stop his momentum and head the other way, reaching up to high-five an unsuspecting O's fan before firing a strike back to the infield to double-up the runner at first.
That man turns 43 today and -- in case you were wondering -- he's still got it:
So it's safe to say that age is just a state of mind. The glory days are now.