Wegner
Rookie
Open stance should be the preferred coaching method, especially with young children, for forehands and 2 handed backhands, exemplified by Serena Williams, World #1. Open stance has been derided as causing hip injuries by conventional teachers, threatened with changes that deeply affect the coaching profession. That was just an invention to fight change to more modern and effective ways.
Here is what the USTA says about it, in answer to a question in that regard:
"Unfortunately, most tennis injuries are multifaceted so there are few easy answers to injury questions. There are no studies that statistically link open stance tennis strokes with higher rates of certain injuries at the hip joint. Most tennis players could benefit from strengthening hip musculature in all directions (flexion/extension and abduction/adduction). Most players should also stretch the muscles around the hip in all directions too. One recent study of tennis professionals found an association between flexibility losses of hip internal rotation of the lead leg and lower back flexibility.
Hip flexors are muscles on the front of your hip and thigh that help you quickly swing the leg forward as you run about the court. For most players strength is not the issue but flexibility. If your knee is strong a good stretch is to bend your knee and grab your foot behind you and gently pull your leg backward. More advanced stretches are splits (rear leg) or elevating your leg behind you and placing the top of your foot on a short bench/fence.
One of the hip flexors (rectus femoris) crosses both the hip and knee joints, so combinations of hip extension with and without knee extension will allow you to focus stretching on this superficial muscle or the deeper hip flexors in the pelvis/lower back. To reduce the risk of painful hip flexors one should both strengthen these muscles away from the court and stretch them to maintain their flexibility."
Here is what the USTA says about it, in answer to a question in that regard:
"Unfortunately, most tennis injuries are multifaceted so there are few easy answers to injury questions. There are no studies that statistically link open stance tennis strokes with higher rates of certain injuries at the hip joint. Most tennis players could benefit from strengthening hip musculature in all directions (flexion/extension and abduction/adduction). Most players should also stretch the muscles around the hip in all directions too. One recent study of tennis professionals found an association between flexibility losses of hip internal rotation of the lead leg and lower back flexibility.
Hip flexors are muscles on the front of your hip and thigh that help you quickly swing the leg forward as you run about the court. For most players strength is not the issue but flexibility. If your knee is strong a good stretch is to bend your knee and grab your foot behind you and gently pull your leg backward. More advanced stretches are splits (rear leg) or elevating your leg behind you and placing the top of your foot on a short bench/fence.
One of the hip flexors (rectus femoris) crosses both the hip and knee joints, so combinations of hip extension with and without knee extension will allow you to focus stretching on this superficial muscle or the deeper hip flexors in the pelvis/lower back. To reduce the risk of painful hip flexors one should both strengthen these muscles away from the court and stretch them to maintain their flexibility."