Body position is paramount when talking about hitting mechanics. We can discuss all sorts of details, but if the body is not positioned correctly, nothing else will fall in place.
When talking about tilt, we are talking about the way that the body is positioned when looking at a hitter from the pitchers perspective.
What should this position look like?
One of the biggest mechanical changes I try to make in a player's swing is to get them to drop their back shoulder. You can check out that article here. As important as getting the back shoulder down is maintaining it throughout the swing. At contact, a hitter should look something like this:
The biggest components of this position are maintaining the back shoulder down, having the head out in front of the feet, and the bend in the side of the body closest to home plate.
In addition, plane of the bat should match the plane of the shoulders. Like this:
Why is this important?
Keeping the back shoulder down and keeping the upper body tilted over home plate allows for 2 major components of successful hitting: Proper bat path and generation of bat speed.
Proper bat path:
Keeping this tilt throughout the swing allows the batter to get the bat underneath the baseball and work up through the hitting zone. The bat and hands should be moving up through contact. Like this:
When a hitter cannot get to this position or fails to maintain it through contact the hitter tends to work down or level through contact. This decreases the hitter's chance of making good contact and decreases their ability to hit line drives or driven fly balls.
One of the biggest components of generating power in a swing is the hitter's ability to stay connected. This means that they are able to keep their hands connected to their back shoulder for as long as possible to allow the bigger stronger muscles in the body to create power.
If the hands have to disconnect from the body too soon, bat speed will be reduced and power will drop.
How do we work on this?
Here is one of my favorite new drills for getting players to feel this position and maintain it.
1. Start in launch position (Athletic position, hips back, chest leaned forward) with head on pole.
2. Slowly rotate until the knob of the bat faces the pitcher, keeping the head on the pole with back shoulder down.