Ground rows, forearm flexor carpi ulnaris pain

Hi, 

I am currently doing foundation 1 and when I am doing ground rows, I feel pain in my forearm(flexor carpi ulnaris). It is not like shooting pain, but something that makes it tight and as a result I have to really stretch my forearm and wait to continue to my next rep. 

My question is: 

What might be causing this? 

Am I over-estimating and go back to previous level? 

Are there any stretches that help with this?

Thanks in advance!

Nikhil

Have you got the HeadStand courses? There are some useful wrist stretches which gradually build forearm strength as too do many of the exercises. I also did some assisted hangs. My issue was and still is grip strength and forearm strength but I did find perseverance with time in hang and wrist work helped. You may find that you simply make slower progress in this area. At a time I could do good pullups with weights and rope climb without using my legs but I still struggled with ground rows. 

I had surgery on both of my wrists and just recently got over this type of pain doing rows. It was just my forearms being weak from lack of use. I couldn't jump from incline rows to ground rows immediately. I had to gradually decrease the ring height every few weeks until I was at ground row  level.  That solved my issue.