Since the middle of the year I had been suffering from a tight piriformis on my left side and associated pain down my left hamstring. It was really niggly, especially after my long run. I was spending a lot of time stretching and doing stregtening exercises with little success.

I had also been nursing a food tendonitis issue so had been off running for a month during which time I picked up Pilates again. My instructor got us to think of our pelvis as a bowl of water that shouldn't be tilted backwards or forwards. She got us to perform our moves with the (imaginary) bowl level so that no water would slosh out. This is known in Pilates as neutral spine.

Anyways, I totally got this and even connected it with my normally bad posture, which I tried to correct in my daily life (when I remembered), but for some reason I didn't make the connection with my running form. Finally one day over a month ago as I started my run with piriformis pain I thought this is bullshit, gotta try something new, so I tried keeping my pelvis level. It felt like I was tucking my tailbone under and pushing my hips forward. For the first week or two it seemed hard to maintain, but felt kind of good and now it seems to have become a normal part of my gait.

Amazingly, just by doing this my piriformis issues have all but disappeared. Yay!

I had always been of the school of thought not to mess with that gait stuff, but a recent video of me finishing a race made me realise just how terrible my gait looked. I hope I look less pathetic now.

I'm trying to figure out tucking the tail bone and pushing the hips forward.  Tucking my tail bone pulls my hips back.  Maybe I'm hooked up backwards (which could explain a lot of things!)

But any fix that works is good news, especially piriformis.  I'm going to work on this.

OMG, I have been fighting the same sort of symptoms the last few months, tight piriformis and tendonosis.  I am definitely gonna try this tonight on my run and see if it helps.  Is the form you tried sortof like feeling your scrunching your butt forward, or as they say in the Rocky Horror Picture Show - the Pelvic thrust?  Thanks again.

Um, yeah, kinda like that.

I read somewhere that it should feel like your glutes are doing the most work to propel you forward. I never realised what a big difference a small change could make.

In this thread, people are saying things which, while anatomically scientific and helpful, might lead one to believe they are things which are, in fact, naaaaaaaughty!  Yeah baby....

Good tip!