What do the baby in this picture and the tennis player in this video have in common? They are both using their glutes (hips/core) during their movement. Most people I see do not use their glutes well. They force too much movement at the spine instead. This wastes power, causes premature fatigue and sets people up for over-use injuries and poor movement habits throughout the rest of the body (kinetic chain).
Thanks for reading and remember to use your Glutes!
Eric Beard
Corrective Exercise Specialist
Athletic Performance Enhancement Specialist
Tennis Power and Biomechanics