Not sure how long i've been doing body step but i remember being at the launch of Bodystep 2 in Birmingham, England, but i've never had an injury from doing step (even old school freestyle when i used 3 risers). In addition to myself 2 people in the bodystep class i go to have complained about achilles heal problems. My calf hurt after my first time through and on the second time, after i had completely sussed the knee moonwalk combo and could really put some energy into it, i seriously pulled my calf and had to stop. 2 weeks of limping and no step followed. My achilles heals have been giving me trouble ever since. This coincided with me buying new trainers which appear to have contributed to the injury. I have changed my trainers and with BS 77 they are getting better. Maybe doing those moonwalks twice in one release is just too much