I have run improperly in my VFF for about a year. A few weeks ago, I learned how I was suppose to run barefoot or with VFF. The new technique is not yet natural, but I feel great when running. However, my glutes, especially the left side, are amazingly sore. I even had some nasty muscle spasms. My calves and hamstrings are also sore, more so on the left side, but nothing so extreme. I do stretch after warming up and after my run. Is there something wrong with my technique that is causing so much tightness, or is this just my muscles adjusting to the correct technique? Should I be concerned that the tightness is mostly on my left side? Thanks in advance for any advice!