Take up rock climbing
More realistic answer is assisted pull-up machine for one exercise, though this only somewhat mimics the pull-up as your body doesn't hang at the same angle, so the pulling angle is quite a ways off.... so supplementary work in both slow negatives and static holds in various positions of the pull-up with full bodyweight work really well.
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Fuck. All you guys who do high intensity intervals on a regular basis... I have mad respect for you. I just did my first interval workout in about 2 years. Hill sprints with a 15 kg weight vest on. I almost threw up after the 30 min. Couldn't even go into the rest of my workout without a 30 min break to recover.