Posted by: Chuck (Chuck10112@gmail.com) on Mon Aug 11 13:08:31 2008

This is going to be difficult to explain so bear with me.

I'm tired of hearing coaches say that the power source of a swing comes from the inward turn of the back leg. This well intentioned but incorrect advice has prevented/stalled players, including myself, from experiencing their full power potential.

The real power source of a baseball swing comes from the sideways hip thrust towards the pitcher. Once the hips begin moving toward the pitcher the legs simply redirect the energy generated from that linear movement into semi-rotational energy.

The reason coaches/instructors don’t pick up on this movement is because it’s EXTREMELY subtle, it’s not an exaggerated movement. Even when analyzing slow-motion video you might not be able to recognize it. Another reason this movement isn’t acknowledged even if it is seen is because it’s such a small movement, it’s natural to assume that such a small movement couldn’t be the cause of a 400ft blast, but then again it’s natural to think that the splitting of a microscopic atom couldn’t destroy a whole city.

Although the hip thrust is subtle, there are a few clues that it does occur.

1. If you look at a frontal (pitcher’s mound) view of a major league hitter’s swing at contact you’ll see that the hips stick out slightly (for a righty they’ll be toward the third-base side, for a lefty they’ll be toward the first-base side). Watch the finish also, the front leg of the hitter will sometimes experience such a powerful pull force that it will actually move over a bit towards (third base for righties and first base for lefties). Now if the swing was simply a powerful rotation on a stationary axis the front leg would have the tendency to open up but not move over.

2. The second and most obvious clue that hip thrust occurs is the back foot. (Jack this is where I disagree with you) At CONTACT a Major League Hitter’s back foot will be on the toe, sometimes so much force is generated that the back foot is in the air or is being pulled forward. This is the biggest hint that the back leg isn’t driving the hips but rather the hips are pulling the back leg. The inward turn of the back leg simply allows your hips to continue moving without resistance but they don’t cause the hips to move. If I’m holding onto the leash of a dog trying to run away and I let go of the leash I allow the dog to run away without resistance but I don’t cause the dog to run away. The inward turn of the back leg releases the hips, it doesn’t push the hips.


33.3% of biomechanical movements is creating the maximum load (Potential Energy)
33.3% is channeling the forces for optimal delivery (Kinetic Energy)
33.4 is minimizing internal resistance.