Keywords: 1-repetition maximum, 1RM, maximal strength
What is 1RM testing?
The one-repetition maximum (1RM) test is often considered as the ‘gold standard’ for assessing the strength capacity of individuals in non-laboratory environments (1). It is simply defined as the maximal weight an individual can lift for only one repetition with correct technique. The 1RM test is most commonly used by strength and conditioning coaches to assess strength capacities, strength imbalances, and to evaluate the effectiveness of training programmes (2).
Despite previous concerns, various 1RM tests have been shown to be a safe and reliable measure of strength in young children (6-12 years) (3), adolescent athletes (15-17 years) (4), healthy trained and untrained adults (18-36 years) (5, 6, 7, 8, 9), untrained middle-aged individuals (50-52 years) (1), post-menopausal women (54-60 years) (10), patients with cardiovascular disease (11, 12), and individuals aged 75+ (13, 14). As this test is simple, time effective, inexpensive, and reliable, it is a very popular testing protocol (15).
The diversity of the 1RM test means that it is not limited to only one exercise, instead it can be conducted using a wide variety of exercises such as: back squat, leg press, leg extension, leg curl, bench press, chest press, lat pull-down, seated low row, and the Olympic Clean – to name just a few. Though previous research has been conducted on these exercises, it is important to ensure that the exercise you wish to use has been proven as a reliable predictor of 1RM for your chosen population before conducting your test.
For example, whilst the safety and reliability of 1RM back squat testing has been proven in healthy young adults (7), no research to our knowledge has demonstrated that this is a safe and reliable predictor in individuals of 75 years and over. However, although the 1RM back squat has not been proven to be safe and reliable in the elderly population, exercises such as the lat pull-down and the bench press have been (13, 14). Therefore, knowing that your chosen exercise is both a valid and reliable measure of 1RM strength before conducting the test is vital.
IMPORTANT: It has been suggested that novice lifters should not perform a 1RM strength test, simply because lifting maximal weight by individuals not accustomed to weight training may induce large degrees of muscle soreness and increase the risk of a more serious injury (2, 16).