I have just started barbell training following the stronglifts 5x5 program. Since I am having some problems with the squat I am taking some lessons from a personal trainer. In the first session he measured my mobility and found that I have poor dorsiflexion in my ankles. He suggested some mobility exercises. I also have the book "Becoming a Supple Leopard" and in it I find several other mobility exercises for the ankles. When doing squats I also tend to get pains in my adductors. Looking in the same book I can find several mobilizations for the adductors.
However, are not both my trainer and the author missing the point?
I watched this interesting video on youtube: Why Stretching Isn't The Answer by Dr. Quinn Henoch. He basically argues that poor flexibility is the symptom. Poor strength (in another muscle) is the cause.
Another interesting video on youtube makes the same point Improve Squat Mobility Instantly Without Stretching Following this video it seems that front planks could help with the pain in my adductors. This seems plausible since I am terrible at them.
I also think that training the adductors will help: Adductor Work for Added Gains and Construction by Adduction. For balance I should then also train the antagonist which would be glute medius I think.
For my ankles I think standing on one leg style exercise will help.
I think mobility exercises are important, but only in conjunction with strength training of the neglected muscles. As an example I trained my adductors yesterday for the first time ever probably. My range of motion was horrible. But if I combine mobility with training the adductors, they will gradually relax and normal range of motion will be restored.