Managing "Good" Pain in High-Rep Isolation Work: When to Push Through?

I’ve been lifting for a few years, initially focusing on strength but recently shifting to hypertrophy with more isolation exercises. I’ve been using high-rep (10-30) sets for exercises like biceps curls, triceps extensions, calf raises, etc., with a focus on stretch-mediated hypertrophy and double progression. So far, I’ve made good progress.

However, as my strength has increased, I’ve started experiencing discomfort during sets. For example, with biceps curls (15-20 rep range, lying on a decline bench for added stretch over the shoulder joint), the stretch becomes progressively painful around rep 10, reaching 8/10 discomfort by the target rep range. It always feels like the “good” kind of pain, and the discomfort dissipates immediately after the set. I don’t feel traditional fatigue—just an uncomfortable stretch. After 3-4 sets, I get huge pumps, which feel great.

As an amateur coach myself, I wouldn’t ask a client to push past around 3/10 pain. In my own training, I’m wondering if it’s okay to push through this discomfort to continue progressing.

Question: Is this where the “no pain, no gain” mentality comes from, or is there a better way to approach this? Is there a downside to pushing through this discomfort, or would it be better to adjust the rep range down while increasing the number of sets? I’m not concerned about injury, but I want to make sure I’m training smart.

Hey Mark,

Welcome to the forum and thanks for posting.

To your question, I do not know the origin of no pain, no gain. However, the discomfort you describe does not sound concerning. Training to/near failure is pretty uncomfortable.

I am not sure that your programming aligns with what I would personally go for, but if you’re getting good results, carry on. My biggest push back is about focusing on stretch-mediated hypertrophy, as I do not think this is what you’re doing while lifting weights, nor very useful for muscle growth. Stretch-mediated hypertrophy typically refers to stretching outside of lifting weights. I do not think it drives lots hypertrophy for most people, especially thsoe who are lifting weights.