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.

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.

You can do more sets with shorter rests to match the total work of fewer sets with longer rests—and you’ll still get the same muscle growth and strength gains.

Lifting heavy weights for fewer reps and lighter weights for more reps both build muscle about the same in young men when you push yourself to the max, showing that the total work done matters more than how heavy you lift.

How much you lift in total each week matters more for results than whether you do it in 2 days or 5 days—unless you’re trying to get stronger, then frequency helps a bit.