Isometric stretching required, how do I fit it in?

[Gym1]

Hi, I am 42 years old and train gymnastics class three times a week (at least 40 mins of cardio & conditioning). I also run two other days. I need to greatly improve my shoulder flexibility and also want to achieve splits three ways (I have my front left splits most of the time)! I bought your book stretching scientifically, which I find fascinating and gather I need to do isometric stretching! I'm just not sure where to fit it in, especially as I often feel a bit of muscle pain after a particularly intensive gymnastics class. Can I just do 15/20 mins of isometric stretching at home some days with no warm up? Thanks for your time.

[Thomas Kurz]

Yes, you can.

[Gym1]

Thank you for prompt reply.