Using rings, TRX, or Blast Straps allows for a more natural rotation of the arms, so it feels much better if you have busted up wrists or shoulders. Beyond being more joint-friendly, setting the suspension device up wider than your wingspan makes it a lot harder – the straps will want to go out so you have to squeeze hard to counteract that force and keep them on the right path, which makes for a huge contraction in the lats.

Keep in mind that they're a lot harder than regular pull-ups, especially if you're strict on the form, so don't expect to hit your usual numbers, but expect your lats to be fried more than normal. You've been warned.