The launching phase takes us from the end of the loading phase to the contact point with the ball and it consists of 5 noticeable movements: 1) the continuation of the timing step, 2) the opening of the hips, 3) the forward rotation of the spine, 4) the pushing and pulling action of the arms and shoulders and 5) the guiding action of the hands on the bat.
In this section we will define the movements and muscles involved with the continuation of the timing step.
The timing step began in the loading phase when the front leg was raised off the ground and the player’s weight was momentarily rocked onto the back leg as seen in Figure 4-1a. Now the continuation of this timing step, where it begins to return back to the ground, is the first part of the launching phase as seen in Figure 4-1b.
Depending on the player’s technique, the timing step of the front foot can actually be a short stride towards the pitcher by a few inches and perhaps more, or it can simply be placed back down on the ground as shown by our player’s technique in Figure 4-2.
But whichever technique is used, the lowering and turning of this timing step outward, to the ground, triggers the initiation of the swing.
This outward turning of the timing step is caused by muscles acting higher up in this player’s left hip known as the External Hip Rotators and it forces the toes of the player’s left foot to point outward, in the direction of first base, as seen in Figure 4-3.
Now, compare the player’s left foot position in Figure 4-3 above with one while in the stance position seen in Figure 4-4 below, and you can see this repositioning more clearly.
The names of these external hip rotator muscles in the player’s left hip that turn his foot outward, down toward first base, are the Superior Gemellus, Piriformis, Obturator Internus, Inferior Gemellus, Obturator Externus, Quadratus Femoris, Gluteus Medius and Gluteus Maximus. These muscles can be seen in more detail in Figure 4-5.
Since a lot of one’s batting power comes from hip rotation, the repositioning of the timing step, where the toes are now pointing outward down toward first base, is necessary since this starts the opening of both hips toward the pitcher, which is the direction the batter will end up facing at contact. See Figure 4-6.
Now the contraction of the player’s left external hip rotators (Figure 4-5 previous page) to point the toes outward will load, or stretch, the antagonistic or opposing muscles in this same left hip, namely the Internal Hip Rotators. The Internal Hip Rotators are the Gluteus Minimus, Gluteus Medius and Tensor Fascia Lata and these muscles can be seen in more detail in Figure 4-7.
You may have noticed that the Gluteus Medius is both an external and internal hip rotator and this is because the anterior fibers of this muscle cause internal hip rotation and the posterior fibers of this muscle cause external hip rotation.
Now these internal hip rotator muscles in the player’s left hip will soon be called on to contract and help further pull the player’s hips around in the swing when he is closer to the contact point with the ball as seen in Figures 4-8a through 4-8d.
In the next section we will talk about the second noticeable movement during the launching phase, which is the opening of the hips, and identify the muscles involved with it.