One-repetition maximum (1RM)


Or 1RM in weight training is the maximum amount of weight that a person can possibly lift for one repetition. It may also be considered as the maximum amount of force that can be generated in one maximal contraction.

One repetition maximum can be used for determining an individual's maximum strength and is the method for determining the winner in events such as powerlifting and weightlifting competitions.

One repetition maximum can also be used as an upper limit, in order to determine the desired "load" for an exercise (as a percentage of the 1RM). Weight training protocols often use 1RM when programming to ensure the exerciser reaches resistance overload, especially when the exercise objective is muscular strength, endurance or hypertrophy. By understanding the maximal potential of the muscle, it is possible to reach resistance overload by increasing the number of repetitions for an exercise.

Why Is It Important To Know Your Limit?

This calculation allows you to:

How to Calculate the Ceiling: The Formula

When it comes to 1RM calculators, there are multiple equations that can be used. The two most popular tend to be the Brzycki and Baechle formulas. 

Brzycki formula:

Baeche formula:

it's important to note that it is a rough estimate, and the result may vary based on several factors, including fitness, running technique, and freshness level.

Make sure you have good technique and are supervised by an expert when attempting your maximum. Use this tool as a guide to plan your workout, but not as the only indicator of your strength capabilities.

The maximum should only be one part of your overall training program to achieve your fitness goals.