The stride—movement of the front leg before contact—might be the most over taught aspect of the baseball swing. Personally, I don’t care how a hitter strides, as long as they stride to balance. Some hitters, like Juan Gonzales, kick up their front leg as if they were pitching. Other hitters, such as Chipper Jones and Sammy Sosa, bring their front foot back and forward quickly as if they were tapping the ground. Other hitters, such as Jeff Bagwell, do not stride at all—they just pick their front foot slightly off the ground and put it back in the same spot.
Whatever is comfortable with the hitter works for me, as long as certain rules apply.
In addition, regardless of how a one strides, all successful hitters stride to a balanced position. The phrase “stride to balance” is often used to further describe this aspect of the swing.
First of all, hitters must not over stride, or stride out too far. This results in an unbalanced position that prevents the baseball hitter from making a powerful move towards the ball.
Secondly, baseball hitters must stride with their front foot at or very close to a 45 degree angle. A wide open foot while striding prematurely releases the hips, thus decreasing the hitter’s power and plate coverage. A closed front foot locks up the hips, thus preventing the hitter’s ability to create maximum rotation. Striding with the front foot close to a 45-degree angle enables the hitter to maintain both their posture and balance throughout the swing while correctly laying the foundation for a proper hip rotation.
Finally, and most importantly, baseball hitters must not move forward when striding. Moving forward during the stride, otherwise known as a "dive move," causes the hitter to lose all balance and power.
Ultimately, when the hitter strides, the head should remain over the rear knee. During the stride, there is only slight linear motion forward. Once the front heel drops to the ground, the linear aspect of the swing is over. There is no more movement forward.
The dropping of the front heel acts as an anchor that stops the hitter’s momentum from going forward. After the hitter’s front heel is firmly planted on the ground, the hitter moves rotationally to the baseball.
By keeping the weight on the backside and minimizing forward linear motion during the stride, the hitter is able to keep his upper body still, mainly his head. This allows the hitter to see the pitch better, which in turn, increases his ability to make consistent contact.
While it is hard enough to hit any moving object, it is much harder to hit that moving object when you are moving too.
Keeping the head still enables the hitter to see the plane of the pitch more accurately. Remember, hitting is sight-oriented. No matter how good one’s baseball hitting mechanics are, nobody—not even Ted Williams—could hit blindfolded.