HOW MANY REPS TO BUILD MUSCLE? HOW TO CHOOSE THE RIGHT WEIGHT FOR ANY EXERCISE?
WHO DOES THIS APPLY TO?
This easy guide is for you if you’re:
- A BEGINNER
- RETURNING TO THE GYM after a long lay-off
- Performing the same exercise with different weights or machines from what you’re used to, i.e. training in a different gym.
WHY IT’S IMPORTANT
It’s important to know how much weight you should use on an exercise so that you can:
- Avoid injury
- Perform an exercise correctly
- Fulfill your potential by making suitable progress toward your goal(s)
To figure out how much weight to lift, you can use two indicators: the Rate of Perceived Exertion (RPE) and Reps in Reserve (RIR).
RPE is on a scale of 1-10 with 10 being maximum effort.
RIR is the number of reps remaining until you reach failure.
RPE standard
10 | Can’t complete 1 more rep or more weight (Failure) |
9.5 | Can’t complete 1 more rep but could go slightly heavier |
9 | Can do 1 more rep |
8.5 | Can do 1 more rep, possibly a second |
8 | Can do 2 more reps |
7.5 | Can do 2 more reps, possibly a third |
7 | Can do 3 more reps (Basic Intensity) |
5-6 | Can do 4-6 more reps |
To be accurate with your RPE you’ll need to, at some stage, test the maximum number of repetitions (RM) you can perform on an exercise for a given weight.
When doing this, you should preferably film yourself taking a set to failure so that you can study how your form is.
After determining the training intensity(weight), the next step is to establish the target reps per set. It’s often believed that to build muscle you need to lift heavy weights, usually around 10–12 repetitions.
This isn’t wrong but it’s not the only way to build muscle. According to science, you can gain muscle using a rep range of 1-35 repetitions. But first, you need to ask yourself: What’s your goal? BUILD MUSCLE? INCREASE STRENGTH? BUILD ENDURANCE?
To effectively train your muscles, select reps per set based on your goal. The following table can help:
1-5 Reps (heavy weight) | 6-15 Reps | 16-35 Reps (light weight) |
More Strength | SWEET SPOT | More Endurance |
Rarely training to failure if at all | Train closer to failure and to failure more frequently |
If you want to use light weights to build muscle, you must train very close to failure and failure often, which is suitable for beginners. Better train using a variety of repetition ranges but mostly in the 6-15 repetition range.