If you lift weights until you can’t do another rep vs. stopping just before failure, you end up doing about the same total amount of work over eight weeks — same number of reps and same weight lifted.

Stopping a few reps short lets you do about the same total amount of work over weeks as going all the way to failure — because you can recover faster and do more sets without burning out.

You can’t just count how many reps you do to know if your workout is good enough — how long your muscles are under strain matters just as much, maybe more.

When you lift weights, how much total work you do matters more for getting stronger and bigger than whether you use heavy weights with few reps or light weights with many reps.

To test if rest time matters, researchers made sure both groups did the exact same amount of total lifting—so any differences (or lack of them) must be due to rest time, not how much they lifted.

When lifting heavy weights, doing more total reps and sets (higher volume) makes your muscles grow bigger, even if you rest less between sets.