The fitness world has several concepts that are common to various types of sports, but there are other concepts that are characteristic of only one.
RM and RIR are two examples of concepts that belong to the world of fitness and are usually associated with bodybuilding or Cross Training.
Many of you should question the significance of these two acronyms and what that has to do with training.
Both relate to techniques that are directly related to the intensity – another concept of the fitness world that is linked to training and physical performance.
To better understand what the intensity is, you can see this blog article.
In this article, I will help you to demystify these concepts a little so that you can better understand your training, know how to listen to your body, adapt to the requirement of exercises and understand what the best technique to use in order to achieve your goals.
RM – what it is?
Let’s broke it in pieces:
“RM” (maximum repetition), or “1RM” (one maximum repetition), in bodybuilding means that, that load, is the most you can lift for one repetition. I mean, even if you wanted to, you couldn’t do another repetition.
1RM is formally defined as:
“(…) the maximal amount of weight that can be lifted through the full range of motion, for one repetition, with proper form.”
For example, you would do a squat with a bar of 100kg once, and the second time you could not climb without help – this meant that you were near or in your 1RM. If you did 10, you’d be close to 75% of your 1RM.
This method is very used in gyms to define the loads with which you will work on your plan.
In other words, ideally you test your 1RM and from there, according to your goal, your training will be planned.
For example, in the case of a hypertrophy workout, the values must be around 70-80% of 1RM.
So, if your “1RM” in the bar squats is 100kg, you should put 70kg on the bar and perform 10 reps, for example.
There are some formulas to calculate the 1RM. However, the most used is trial and error.
Tips on how to calculate the 1RM
One of the ways to calculate this value is to put weight gradually until you can perform a repetition.
The other alternative is to “exaggerate” the weight and take the load slowly until you get that repetition.
After knowing what your maximum-1RM = 100% – when you see a training plan, for example, that you have to perform the exercise at 70/80% of 1RM, you can make a simple rule of three:
100kg – 100% (1RM)
X – 70% (de 1RM)
=
70kg
The big problem with this method is that it is not practical.
As you may have noticed, it is a process that can take some time, as maximal efforts require rest time.
In addition, after so many attempts to ascertain your 1RM, probably this value is no longer real, because there is already some accumulated fatigue.
Another major problem in this way of “calculating your 1RM” is the fact that the 1RM is a static value, which was “discovered” on a specific day (with unique characteristics), so the value will be the same, regardless of whether you are tired of work, you have slept little or eaten badly.
Which is a problem, because our strength fluctuates depending on the days, due to some factors such as those mentioned above.
Constantly working close to the limit causes the total volume of training to decrease, due to the inability of the central nervous system to continue to make muscular contractions of great magnitude.
So other alternatives and other training approaches have emerged to help you calculate your “ability”.
RIR: what is it?
A few years ago, a new approach to training arose – to help calculate the capacity, which took into account the short comings of 1RM and came as an alternative.
Mike Tuchscherer created, then, the RIR (repetitions in reserve), adapting the RPE scale (rate of perceived exertion) created by Gunnar Borg in the 70’s.
The scale of RPE was created to measure the intensity of the training of runners, hence the need to adapt this scale for bodybuilding.
As the name implies, the RIR scale serves to measure the intensity of the training in a simpler way. The scale goes from 1 to 10 in which:
Rating | Description of perceived exertion |
1-2 | Little to no effort |
3-4 | Little effort |
5-6 | 4-6 repetition remaining |
7 | 3 repetition remaining |
8 | 2 repetition remaining |
9 | 1 repetition remaining |
10 | Maximum effort |
Table adapted from the article “Application of the Repetitions in Reserve-Based Rating of Perceived Exertion Scale for Resistance Training.”
To better understand how this translates into cargo and intensity, see the table below proposed by Eric Helms in the book “The muscle and strength pyramid”:
Ratings | Description of perceived exertion |
1-4 | The load is too light |
5-6 | Can do four to six repetitions |
7 | You can do three more reps |
7.5 | Can do, for sure, two more reps, maybe three, but not sure |
8 | Can do two more repetitions |
8.5 | Can do one more repetition, maybe two |
9 | Can do one more repetition |
9.5 | It can increase the load can be increased, minimally, but it will be hard to do one more repetition |
10 | Cannot increase the load or do another repetition |
This scale requires a little self-knowledge (body knowledge) to be well executed, however, gives much more autonomy to those who execute it.
The fact that it is not static-like the 1RM – allows to maintain the volume of training, besides being able to be adapted according to the day and needs.
In short…
Both concepts and ways to ascertain the intensity of training bring results. One does not null the other and experts refer that they can be used at the same time.
However, in the long run, the RIR seems to bring more results because it allows to develop greater awareness of training and perception of the limitations and capacities of the body.
Moreover, it is easier to understand whether it is possible to do one or two more repetitions in that set, than to see if this set was the equivalent of 80% of my 1RM.
Do you use any of these techniques? Share with us!