I think that's why we need to start light. Really widens that line out a lot, and when you do overdo it and hurt yourself it won't be by much. Working to failure is good; it means you've done all you can and aren't slacking off by not working hard enough, and the best definition of "failure" I've seen is "form breakdown", e.g. you can't control the weights, or you need to start swearing to do another rep. Work until you can't, then stop. As you get used to exactly where that line is, you can go heavier.

Personally I'm using 3 sets of 15 as a guideline. If I can't get anywhere near that then it's too heavy. If I can nearly do it then I need to keep working on it. If I can routinely exceed that then it's time to go heavier.

IANAPT, started on this a few months ago, just sharing what I've picked up so far. Of course there are lots of different views on how many sets of how many reps you should do, but bear in mind what works for A won't necessarily work for B, especially if A is a chiselled Greek god and B is a somewhat lardy me who can literally roll up to the gym.

[–] [email protected] 2 points 5 days ago* (last edited 5 days ago)

doing lots of reps on something well within your range also trains your endurance, which is generally pretty important and something that people who just want big biceps can easily forget.