[Ed's note: Be sure to check out the video too!]

Call it a suspension of disbelief. When third baseman José Bautista — and several of his fellow Pirates — works his upper body, all he needs is a pair of nylon straps. Developed by a former Navy SEAL for exercise in tight spots (like, say, on a submarine), the TRX system converts gravity and the user's weight into a taxing core workout.

Leaning back on his heels, Bautista grabs the straps and pulls himself up with a biceps curl. "With dumbbell curls," explains Pirates trainer Frank Velasquez, "there are two points of no resistance — the bottom and top of the rep. With the TRX, resistance is constant." Not to mention that to do the same workout with weights and machines would take three times as long. Bautista's usual routine includes a variety of positions. In one, he puts his hands in the straps and does a push-up; in another, he slips in his feet for sideways stomach crunches. Shortening the cords tweaks the level of difficulty. "In baseball, there's a lot of pivoting," says Bautista. "A strong core helps you swing and throw." Now we'll see if the TRX enables Bautista and his Bucs to hang with the big boys for a while.