Rowing machine, but that's in addition to your weight work.
The issue with single-muscle (or muscle group) machines is they don't involve all the muscles that would ordinarily contribute to the motion if the machine weren't supporting you in various ways.
Barbells and dumbbells ensure you call upon all the muscles necessary to maintain balance and good form, even those you aren't "targeting."
Admittedly there will be Poalrs smarter on this than I.
cable machines, smith machines and free weights are all equally useful, varying equipment used is guaranteed to give best results.
This, but sometimes exhausting those complimentary muscles can limit growth of the muscle you're targeting. Grip strength in general is an example. Machines allow targeted overload of the particular muscle without having to worry about collapsing or putting the weight down safely
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