Question 1

What is a one-rep max (1RM)?

Accepted Answer

Your one-rep max (1RM) is the maximum weight you can lift for a single repetition of a given exercise with good form. It is the standard measure of absolute strength and is used to calculate training weights at different percentages.

Question 2

Which 1RM formula is most accurate?

Accepted Answer

All three formulas — Epley, Brzycki, and Lombardi — are well-validated and produce similar estimates at moderate rep ranges (3–8 reps). Epley and Brzycki tend to be most accurate for compound lifts. For higher rep counts (above 10), estimates become less reliable across all formulas.

Question 3

How do I use my 1RM for programming?

Accepted Answer

Once you have your 1RM, you can set training weights as a percentage. A common approach: 85–90% for strength work (3–5 reps), 70–80% for hypertrophy (8–12 reps), and 60–70% for endurance or technique work. Programs like 5x5 and linear progression use specific percentages of your estimated 1RM.

Question 4

Should I test my actual 1RM or use a calculator?

Accepted Answer

Estimating with a calculator is safer and more practical for most lifters — especially beginners and intermediates. True 1RM testing carries injury risk and requires significant warm-up. Use 3–5 rep sets for the most reliable estimate, and test your actual 1RM only when it's specifically required (e.g., powerlifting meets).

1RM Calculator

Estimated 1RM

Training percentages

Track your 1RM over time in SteelRep

How the formulas work

Epley formula

Brzycki formula

Lombardi formula

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