after dealing with shoulder mobility & rotator cuff issues for 6 months & having physical therapy that made it worse, i saw an ortho shoulder specialist who not only told me to NOT stop CrossFit, he mentioned Crossover Symmetry which i immediately purchased...after the 30-day recovery program, i saw tremendous gains in both mobility and strength, as well as far less pain during certain moves. i'll continue to use this protocol daily, purchasing the heavier resistance bands as i grow stronger. at my age (60) i'm so glad i found something that is simple to use and truly works!!