Staying Flexible - Preferences ?

I love both.  I find that the yoga helps more with the flexibility while the pilates helps more with toning the abs/working the core.  Pilates will help with flexibility but not as much as the yoga.

I started doing Yoga about a month ago and go to classes 3-4x a week and do it at home some days as well.

It has helped my flexibility a lot and I find it awesome stretching. I bought the Spinnerval Flexible Warrior DVD geared to Triathletes from the BT store and it is broken down into 3 sessions each 30' with one focused on flexibility which is ideal stretching post workouts for me. They have a section that explains how to do different Yoga poses. It is excellent and makes my legs/hips feel so much better after runs.

I do think taking classes is a good way to learn form and get started.

I enjoy the mental aspect of it as well. It is something I hope I can continue to do as my Ironman training ramps up as I see it as a way to take care of my body.