If it seemed like far more gifts than usual were wrapped in long, skinny boxes this past holiday season, there was good reason: New youth baseball bat standards took effect Jan. 1.
As announced by Little League in August 2015, players in the Major Division and below now need a bat that adheres to the new rules, called USABat, that are aimed at producing youth bats that act more like wood. That may sound like an impossible task, but luckily some of the country's top scientists are on the case.
The standards were developed over several years of collaboration between USA Baseball and manufacturers. Louisville Slugger, in particular, ran 3,000 players through its play-testing facility, receiving feedback for its own development process that it also shared with USA Baseball. The primary focus for the manufacturer with its new USABats, which went on sale last fall, was on creating a lightweight bat that minimizes sting and vibration on contact -- a frequent source of feedback received during the testing process -- at an affordable price point for a youth market that includes many players getting into the game for the first time.
"I think in the long run, this is going to be really positive for the game," said Tom Burns, senior product line manager at Louisville Slugger. "It kind of evens the playing field and it puts the emphasis back on the players' ability and the players' willingness to train and work hard and develop their swing.
"It's on them now. We're going to develop products that enhance that, but there's not going to be these huge disparities just due to product now. I think that's good for the long-term integrity of the game."
Before a bat can get the seal of approval (literally -- all certified bats are stamped with a USABat logo), scientists run the new stick through a series of tests to ensure that it meets the new regulations and performs like its wooden counterpart in the batter's box. These tests check the bat's trampoline effect, a measurement of how fast a ball bounces off a bat when it makes contact.
A simpler way to show the trampoline effect is to imagine yourself jumping on a trampoline. When you land, the trampoline springs back and bounces you up into the air. This is the same thing that happens when you hit a ball with a bat and the ball sails into the field, and it is the speed of the ball's "bounce" that is measured in these new regulations.
To test a bat's trampoline effect, scientists conduct laboratory studies, shooting a ball at a bat with an air cannon and measuring the ball's reaction with high-tech equipment such as lasers and high-speed cameras that can capture the speed of the baseball as it leaves the bat. Different materials produce different trampoline effects, which is why a standard has been implemented for both metal and composite bats. 
The results of this testing are USABats that have a similar performance as wood, but are much lighter and stronger than wood, which can be prone to breakage, particularly for inexperienced players with developing swings.
"I think there's going to be more balls in play, and that's going to lead to better fielding, better player development," Burns said. "More of that small-ball kind of game, which I think is great, especially for the youth player who's developing to get those skills of how to play defense, what to do situationally and how to read the game.
"In the long run, we're going to get better, stronger players out of this."
Experiment: Test the Trampoline Effect at Home!
Take a baseball or another ball that is not bouncy. Drop the ball on a table or a desk from about six inches above the surface. How far and how fast does the ball bounce back? Now try dropping the ball on an elastic surface like a drum from the same distance of six inches above the surface. How does the ball bounce against the new surface? You will see that the ball bounces back faster and farther when it contacts the elastic surface. Try dropping the ball on different surfaces to see how they produce varying trampoline effects against the ball, and you'll figure out what these new bats are all about!