So I've seen the following post, but there doesn't appear to be any mention of what the shoulders should do during a single-leg deadlift:
Correct form and technique in single leg db deadlifts in detail
I've been doing this exercise over the last few weeks, and it feels like it's doing wonders for my weak hips and hamstrings.
Only problem is, it seems to be causing issues with my upper / middle back. It leaves my back feeling quite tight / sore... and I'm pretty sure this exercise isn't supposed to work your back like that (bear in mind I'm currently doing it with no weight). There's been times where I've woken up in the morning with what feels like a strained Rhomboid but it eventually dies down.
Originally I wasn't properly doing it with a straight back (I was looking too far up without realising) which really didn't agree with either my upper or lower back.
But I've since watched a lot of YouTube videos and even started filming myself in the gym so that I can check my form. Both of which have been a massive help and I'm pretty sure I've almost got it all down to a tee.
The only thing I can think of which might be aggravating my back, is that sometimes I have trouble keeping my shoulders retracted. And they sometimes round forward slightly.
Could this cause upper back issues despite me using no weight? If not that I'm almost at a loss as to what could be causing it.