Like gymnast rings? That way is much, much harder. It's a basic gymnastics move but for the average guy if you can manage it on the rings you're good and strong. I'd love to have a set of rings to play around on. But the basic bar exercies is a VERY good exercise and I've actually used that in place of other presses or dips and pullups separately. Low reps at first, obviously.
I'm not preaching bodyweight only of course. Or the vest (which is cool). But you can do some really effective stuff if you use your imagination and get yourself past the basic pullup/pushup mindset. Just think about a gymnast.
You should also consider, Go Home Red (need something to call you), prone rows. The reason being is just doing pullups and pushups could actually lead to some shoulder problems. The prone rows would help balance everything out and be another good back exercise. For this you hang under the bar horizontally with your feet propped up on something. If the weights too much you can put your feet lower or even on the floor and build up higher as you get stonger. From the horizontal hanging position you basically row yourself up much like rowing a barbell. Hell, once you start doing them with the vest that would be a very good row exercise comparable heavy barbell rows, unless you weight 90 pounds or something
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If you're really badass you can do a sort of prone row where you bring your body up without anything to prop your feet, though core action only! It's not the same movement but it's a hell of a workout. There are lots of ideas, btw, on that site I linked for the vids.
And don't forget about your lower body!