Surf Stronger DVD with Serena Brooke any good?

I wanted to do some surf related conditioning (out of the water) since I'm able to surf only weekends, so I purchased the Surf Stronger DVD workout. I watched through it and it seems to be intended for the beginner since the exercises are extremely easy, at least for me that is.
If I had known this I wouldn't have got it, but still, I need a good workout routine to keep fit for surfing, anyone suggest the Surf Stronger - Core Training with Serena Brooke DVD? Or is it of the same difficulty... Either that or something else. I'm afraid to use any more of my funds for another disappointment.
Thanks in advance.
If I had known this I wouldn't have got it, but still, I need a good workout routine to keep fit for surfing, anyone suggest the Surf Stronger - Core Training with Serena Brooke DVD? Or is it of the same difficulty... Either that or something else. I'm afraid to use any more of my funds for another disappointment.
Thanks in advance.