I hope you are well.

I gave a massage today on a clients lower limbs (posterior) as they had a lot of soreness and tenderness from running. I am just writing up my notes and I was writing about the techniques I used on the gastrocnemius muscles however, when looking at the muscles diagram is it correct to say that the gastrocnemius muscles are superficial to the tibialis posterior (and some others)? And if so, then how do I know if I am "working" on the gastrocnemius muscles or deeper on the tibialis posterior or some other muscles?

Thanks.