Question 1

What is a 1 Rep Max (1RM)?

Accepted Answer

Your one-rep max (1RM) is the maximum amount of weight you can lift for a single repetition of a given exercise with proper form. It is the standard metric used to evaluate absolute strength and design periodized training programs.

Question 2

Are 1RM calculators accurate?

Accepted Answer

Yes, they provide a very reliable estimate, especially when calculated using a set of 1 to 10 reps. The closer your performed reps are to 1, the more accurate the estimation. If you calculate your 1RM using a 20-rep set, the result may overestimate your true maximum strength.

Question 3

Why do I need to know my training percentages?

Accepted Answer

Training programs (like 5/3/1 or Smolov) require you to lift specific percentages of your 1RM. Lifting at 85-100% builds maximal strength, 70-85% is ideal for hypertrophy (muscle growth), and 50-70% is suited for muscular endurance and technique work.

Question 4

Which formula is used for the calculation?

Accepted Answer

We use the industry-standard Brzycki formula: 1RM = Weight × (36 / (37 - Reps)). This formula is highly regarded in sports science and provides exceptionally accurate estimations, particularly when your performed set is between 1 and 10 repetitions.

1 Rep Max Calculator

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