Repetition Maximum for Weight Training
A repetition maximum (RM) is the most weight you can lift for a defined number of exercise movements. For example, a 10RM would be the heaviest weight you could lift for 10 consecutive exercise repetitions. Your RM is a good measure of your current strength level1 as you follow your weight training program.
One-Repetition Maximum or 1RM
Repetition maximum is often expressed as 1RM or one-repetition maximum. This indicates the heaviest weight you can lift with maximum effort in a single repetition. A 1RM is your personal weightlifting record for a squat, deadlift, or any other weightlifting exercise.
The 1RM measurement is a standard in weight training for marking improvement.1 By establishing your 1RM and tracking it, you are able to observe your progress. It is a precise measure, so it can help you judge how effective your program is. Plus, you get positive reinforcement and a sense of accomplishment when you have a way to clearly see improvements.
How to Safely Test Your 1RM
While 1RM is a very useful tool, it does have limitations. Measuring your 1RM is not simply a matter of grabbing the biggest weight and performing a rep. By definition, you will be stressing this muscle to its maximum and placing yourself at risk of an injury if you don’t do it correctly. You need to prepare to do it properly.
Before measuring your 1RM, perform a few warm-up sets of the exercise to get the muscle ready.1 A warmed-up muscle is far less likely to be injured. The warm-up may seem time-consuming, but it is essential.
Also, allow twenty-four hours of rest time for a muscle before performing a 1RM test. Don’t perform this test in the afternoon if you had a morning workout of the same muscle group.
Finally, always use a spotter. Even with a proper warm-up, the risk of injury is high because of the heavy weight you are using. A spotter is essential in helping you avoid injury.
Test Your 1RM: Step by Step
- Choose which move you are going to test (squat, bench press, etc.).
- Warm up with light cardio activity and dynamic stretching for at least 15 to 30 minutes.
- Do six to 10 reps of your chosen move using a weight that’s about half of what you think your max will be. Then rest for at least one to two minutes.
- Increase the weight up to 80% of what you think your max might be. Do three reps, then rest for at least one minute.
- Add weight in approximately 10% increments and attempt a single rep each time, resting for at least one to two minutes in between each attempt.
- The maximum weight you can successfully lift, with good form and technique, is your 1RM.
There are also submaximal testing methods that can be used to approximate 1RM. These can be safer, but may not be as accurate.
RM in Exercise Instructions
You will see repetition maximum used in exercise instructions. For example, “three sets of 6RM lifts” would mean performing each exercise using the weight you can only lift with good form six times. You would perform all of the exercises and then repeat the sequence two more times (three sets total).
It is also common to see instructions for weights based on a percentage of 1RM, such as, “Six reps at 75% of 1RM.” If your 1RM is 20 pounds for that exercise, you would use 15 pounds of weight when following those instructions.
By using repetition maximum instead of defined weights, people of different abilities can use training instructions (one person would use 10-pound weights while another would use 30-pound weights, for example). They would each benefit from the training effect the exercise sequence was designed to produce. Plus, as you improve your strength, you can continue to use the same instructions but use heavier weights.