While perusing some YouTube videos of pro hitters to show my clients, I came across some more bad instruction (there’s plenty of it) – this time on hitting. I made a comparison video side-by-side of a common myth in hitting – that you can aid the swing by pushing or extending the hands through the point of contact in the baseball swing. This is just not true and not what happens with elite hitters, and furthermore, a complete violation of how you would efficiently use the kinetic chain in the body. Efficient kinetic chain use utilizes ground reaction forces (GRFs) to generate and transfer power from proximal to distal, largest body parts to smallest.
Attempting to engage the comparatively small muscles of the forearms will be counterproductive, as the bat barrel is completely ballistic at the point of contact (something Dr. Alan Nathan proved many years ago).
If your coach believes in this, you should find someone else who has actually read a text or two on kinesiology and understands the high-level swing.