One rep maximum (one repetition maximum, or 1RM) in
weight training, is the maximum amount of weight one can lift in a single repetition for a given exercise. One rep 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 rep 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).
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