Photo courtesy of Ronald DeVilla
A while back I posted an article comparing and contrasting gi vs. no-gi grappling. An issue that I didn't address in that article is that skin-on-mat and skin-on-skin contact gives a different kind of friction than does gi-on-mat or gi-on-gi.
Wearing shorts and a tee, you have a different sort of interface with the opponent and with the mat. Sometimes the skin interface is stickier than cloth (as with skin-on-mat in a warm, humid room) and sometimes it is slicker (as in sweaty skin-on-skin). I remember in college, grappling shirtless with my buddy, Steve, in the yard. I caught him offbalance and sailed in for a hip throw that should have been a sure thing but I slipped off his sweaty arm and busted facefirst into the ground! I had done a sweaty sukashi to myself!
When doing no-gi grappling, you also have to move differently to avoid matburn. Sometimes with a gi you can slide a leg or arm or shoulder across the mat to make a quick transition but often with direct skin contact, you have to pick the limb up off the mat in order to move it.
Bottom line: play both gi and no-gi grappling. You will learn different things under these two different conditions.
Patrick Parker, is a Christian, husband, father, judo and aikido teacher, Program Director for a Cardiac Rehab, and a Ph.D. Contact: email@example.com or phone 601.248.7282