The one rep max (1RM) is a great indicator of strength and fitness level. A true one rep max is the amount of weight you can lift for a certain exercise one repetition only and no more than that. Performing a one rep max can be dangerous. It is an easy way to cause injury, and for most trainees it really is not necessary. But how do you know which weight to start with on a new exercise? You can get an idea based on your 1RM and best yet, you can determine it from doing a test of 10 repetitions. This allows you to use a manageable weight and have less risk of serious injury.

The following equation will convert your 10 rep max weight into your one rep max weight. This is just a guide. If you keep a workout log, then it will be easy for you to know what weights will be challenging for you!

One rep max equation: weight / ( 1.0278 – ( 0.0278 * reps ))

Enter your weight and reps to calculate a One Rep Max:

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