The One-Rep-Max: Assessing your maximum strength— published: 05-04-2012
When you begin a resistance training program, how do you know how much weight you should be lifting? Most muscular fitness programs are designed around lifting a percentage of your maximum strength.
The first step in this process is to determine what your maximum strength is. A popular technique for assessing muscular strength is the one-repetition maximum test (1RM), or the maximum amount of weight you can press once but not twice. Alternatively, multiple repetition tests can be performed as a reliable estimate of maximum strength. One study found that a five- repetition test was the most accurate, but no more than 10 reps should be used to estimate strength. This instructional video will demonstrate the ACSM protocol for a 1RM test. This protocol can also be applied to a multiple-repetition test. For example, determine the maximum amount of weight you are able to lift five times, but not six times, for a five-rep max test. If you have doubts about whether this is the right test for you, be sure to consult your doctor.
The second step is to determine what percentage of your 1RM, in weight, you should use to improve your muscular strength and endurance. Typically, improvements in muscular strength are seen when using 60-80% of your 1RM. Increased muscular endurance is achieved using about 50% of your 1RM. Read more on muscular fitness and more details on how to train for each here. Once you have assessed your maximum strength, use this conversion chart from the National Academy of Sports Medicine (NASM) to determine percentages of your 1RM.