What is that? I do TRX but we don't name much of what we do. This sounds like something I *should* be doing.
planks on your elbows (stomach down) with your feet in the trx loops. bring your knees in as if you were running...horizontally. 20 seconds on, 10 off. times 4.
Works the other way too. Hamstring killer. Back to the mat. Hook your heels in the loops. Get on your elbows and draw your feet alternately towards your butt.
Sounds good! We do pikes and "bring knee up to outside hip" in that position but I haven't tried the horizontal running.