im 17 and i bench 185 how many reps should i be able to do before moving up to 205 for 5 reps and so fourth...
If you're asking this question, it means you should probably start using some sort of set strength training program. That way, you'll have a set plan for progressing.
As for your question though, 5 reps usually works out to be about 85% of your max. So if you're looking to get around 5 reps with 205, it would put your max around 240. 185 is about 77% of 240, which would put you at about 10 reps with 185.
Rep prediction isn't exact, and will vary from lifter to lifter, but if you want to get 5 reps with 205, you should probably be able to get around 10 reps with 185.
But get on a program.
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