Forget Gatorade. This year’s hottest endorsement deal is with Ensure.

So the Social Security set of Major League Baseball continues to rake it in.

On the heels of the Dodgers throwing $18.5 million for two years at old-for-his-age Nomar Garciaparra (a rickety 33), other teams continue to add past-their-prime stars to their rosters.

Greying Mike Mussina (38) re-upped with the Yankees for a slightly less than he was making before ($23 million for two years, as compared with $88.5 million over six).

The Mets have hired Moises Alou (40) for the year, paying him $8.5 million for his services at the plate and in left field. And in a formality, they declined their option on Tom Glavine (41), who is vacillating between staying in New York and going home to Atlanta. Earlier this year, they re-signed Orlando Hernandez (41) and Jose Valentin (37), and added Damion Easley (37) to their bench. Next to fellow benchwarmer Julio Franco, these veterans all look like mere pups. The first baseman (and 1990 All-Star Game MVP!) is 48.

The Reds signed lefty reliever Mike Stanton (39) to a $5 million, two-year deal with a $2.5 mill option for 2009. And, of course, the Tigers earlier gave up young pitching for 38-year old Gary Sheffield, while rumors continue to swirl around 42-year old Barry Bonds.

That makes the biggest deal to get finalized this offseason, Alfonso Soriano’s $136 million with the Cubs, also the youngest. The infielder-turned-outfielder is just a couple months shy of his 31st birthday and will be 39 when his deal with the Cubbies runs out. (Though, as Nick pointed out, he hits like he’s ten years younger, so maybe the Cubs were just confused. Or drunk.)