What is a weight shift in a swing? We have always heard about weight shifting in the swing but I think “back to front” can be a dangerous way to think about this in the swing. When hitter’s hear “shift” the weight, it implies a “one side to the other” occurrence.
The discussion is a little complicated. When we look at Pujols, you can clearly see his back foot come off the ground and move forward slightly. In terms of force into the ground, the back foot completely releases from the ground. There is not, cannot be any force into the ground at the rear foot when it is in the air. If there were force plates under each foot, the plates would read 0% at his back foot and 100% at the front foot in terms of percentages. But does this mean his weight has “shifted?”
The definition of shifted is where the confusion lies. In terms of force into the ground, the front foot gets unweighted during the gather. As the hitter moves into contact, the rear foot becomes (briefly) unweighted. So we’re talking 100% back foot, then 100% front foot in terms of FORCE. But force and where you feel your weight can be extremely different.
For me, weight shift has more to do with WHERE your weight is. What does this mean? Think of it in terms of direction of force, not just force. In the Votto screenshot above, the red arrow above shows angle “against” the force at his front foot. Typically, I see the angle from the front foot to the head being in the range of 60-70 degrees with the best hitters. (Votto is at 60 degrees here.)
The teal arrow above shows a force direction being vertical over the front foot. I see a lot of hitters getting too far forward with push/knob to ball style swings. They shift over the front leg to get leverage to push. This swing is typically too steep/downward.
On the other end of the spectrum is hitters who “hang back” too much. These hitters keep force on the back side and don’t shift that “percentage of force” fully to the front side. Typically, hitters who keep weight on the back foot will have a very upward swing. There are exceptions, but this is what I see most often.
It is interesting that we tell hitters to “stay back” but still “shift their weight.” A great cue for helping hitters with this is to have them finish “middle.” Instead of trying to finish on the front side, have them feel “working from back to middle.” This swing thought can be helpful for hitters who get too far forward or stay back too much. Test it out and see if it is helpful!