Getting Back Into Meditation - and why I keep dropping off

I posted this in my other blog:
http://continuousmind.blogspot.com/2013/08/getting-back-into-meditation.html

I'm trying to recharge again and get back into meditation and mindfulness is something new I'm working on.

I don't know why but I tend to slip in and out of my practice.  I was pretty strong and connected to Yogananda's work via Ananda, until the end of 2012.  Then I slipped into materialism.  I started looking at the teachings and practices again around March of 2013 but I fell off again shortly there after.

I think that Yogananda's teachings are spot on.  Not sure why I keep falling off the daily practice.

Over the past few months I've looked into Zen (Sekida's work) as well as Bhante Gunaratana's work (Mindfulness in Plain English.)  The latter is very open, and easily meshes with Yogananda's teachings.

I feel one bit of resistance inside me, is to this idea of postures, and specific patterns of practice... For example, I see benefit to Hong Sau, but I find it difficult to believe that yoga postures do anything.  Sometimes I feel the energy move in my body, but other then that I don't really believe it.  Perhaps that inner resistance is what's preventing me from moving forward.  After all the teaching Yogananda wishes his students to attain is that of Kriya Yoga.

I think perhaps my doubts on mudra's and positions is causing me to have a inner blockage here.