what is causing my shade leaves to turn over ?

there into there 11 th week now of veg under 600 watt there are doing really well but every now n then they turn there shade leaves over and sometimes they all reach for the sky and push all there leaves up high . i went back to them a few hours l8r and they were back to normal any help please

im not 100% as to what you mean but my thought is you have witnessed your plant trying to stretch.

thats cool all plants are fine growing really really well just wondering about the leaves turning really. thank you any way