I've heard them called the wrist wreckers. Apparently, balancing up on a handle with two thin stilts isn't everyone's idea of a sane workout. Still, the T handle push-up concept is seems to be catching on with those who want to take push-ups to the next level of difficulty. To my knowledge, there are three makers of T handles for push-ups. I ended up making a pair of my own since I wanted adjustability and I just had the urge to make some.
I'll be the first to admit that even the simplest, easiest push-ups on T's are pretty advanced exercises. They're not for someone who has trouble squeezing out 20 plain-vanilla push-ups. For someone with wrist, forearm or hand problems or weakness, I'd hold off on buying or making a set of these. In my opinion, if you can't punch a heavybag without your wrist bending on impact, you should build up strength in your wrist before investing in the T's.
My personal set of T's
The benefit of doing push-ups on T's are numerous. Remember my rant about eccentric training a few weeks back? Well, when you're doing push-ups on the T's, you're using a great deal of eccentric contraction. Since you're so unstable, you have to control all aspects of the movement. There's no dropping to the floor without control on these. This lack of stability demands a lot out of your core as well. This is the benefit of T's that gets mentioned the least. The most obvious, most talked-about benefit of T's is the grip work. This takes the push-up, not normally used for strengthening the grip, and moves it into position to rival pull-ups, chin-ups, and even rope climbing for BW grip strengthening.
I had a pretty good grip and core strength prior to getting my hands on T's I was able to take off running with them, cracking out 20 push-ups on a 2.5" stilt without too many problems. I know many of you aren't so fortunate. Were I someone needing graduation up to using them, I have a few ideas. I'd start out by doing as many of your push-ups as possible on your fists. Once that gets to be easier, I'd throw in fingertip push-ups. Both of these will build up good stability and strength in your forearms. I could do 40-50 fingertip push-ups before I started doing T's. If you've never tried doing elevated push-ups on a stability ball, then you have no idea how hard they are. You need a powerful core to do these. These help too.
If you look back in my blog, you'll find that I wrote a post about using elevation to ease or intensify the difficulty of push-ups. To start out using T's, it might be a good idea to do the push-ups the the T's on a chair, descending only to the bottom of your hands. This will take some of the weight off your upper body, making the exercise a bit easier.
T handles are a great training tool, provided that you error on the side of caution. Believe me, you don't want to do these before your ready or do anything that would put your wrist as risk of collapsing. Falling while on the T's is painful. Take your time, practice and get ready to get seriously strong with these great training tools.