How heavy is heavy enough?

Every program you have ever been handed said something like 3 × 10. Almost none of them told you how heavy, which is the part that decides whether it works.

Reps in reserve

At the end of a set, ask: how many more could I have done with good technique? That number is your reps in reserve. Most work in a first block should finish with two or three left — hard, controlled, not a grind.

• —Finished with five or more left? Add weight next session.
• —Two or three left? That is the target. Stay there.
• —Nothing left, or technique broke down? Too heavy. Come back 10%.

Beginners routinely underestimate how many they had left, which is fine — the estimate gets accurate within a month or two, and the loads climb on their own.