Many people have the opinion that ten reps in a set is a so-called ideal number to achieve hypertrophy or muscle mass. This is partially true since each number of reps leads to hypertrophy, but this number of reps is far from the ideal. There are many hypertrophy training routines, but you are probably wondering which number of reps is ideal or does the ideal number of reps even exist.

Should you do more reps in a set with smaller weights, or should you do fewer reps with bigger weights? We will answer that, but we will leave the conclusion to you.

bodybuilding performing cable chest flys

More Reps In A Set

During the workout in which you do more reps in a set, you have probably noticed that your muscles get pumped and create a feeling like they are growing. That feeling is called Muscle Pump.

This feeling is misleading since it creates an illusion of pumped muscles, but that is nothing but an increased blood flow to the muscles that you are activating during your training.

Of course Muscle Pump has its good sides too and we will get back to it, but if our goal is gaining muscle mass, then Muscle Pump is not primary.

Let us explain a bit better what we said so far. With a larger number of reps we activate slow muscle fibre or muscle fibre type I as well as type IIA muscle fibre that is in the group of fast muscle fibre.

With the larger number of reps we cause hypertrophy of muscle fibre, but their growth potential is not that great or better be said their growth potential is not as good as the growth potential of some other muscle fibre, but we will talk about those later.

I am sure you are wondering why do sets with more reps then? The answer is that with a larger number of reps we cause the so called sarcoplasmatic hypertrophy meaning the growth of fibre type I and IIA and as a result we gain the increase in durability of muscles, increase of synthesis of protein in the muscle and decrease of the degradation of the protein from the muscles during the training.

What Weights And How Many Reps?

So we came to the conclusion that the larger number of reps has its benefits but now we have the question what weights to use to do larger number of reps.

It is only logical that you can not do a set of thirty reps with the weight that is 80% of the maximum in any exercise. There is also a question what is a larger number of reps, how many sets with how many reps you should do and how long should be each break between the sets? This is very important since you do not want to over train yourself .

The larger number of reps will lead to the increase of number of capillaries in the muscle, and that is a base for faster growth of muscle mass. Also, studies show that larger number of reps duplicates mitochondria in the cells.

The lowest number of reps should be fifteen reps in a set, and the highest number should not be higher than fifty. Here is the example (first number are the sets, the second are the reps) :

– 1×50 with the weight you can lift 50 times

– 2×30 with the weight you can lift 34 times

– 3×20 with the weight you can lift 24 times

– 4×15 with the weight you can lift 18 times

You do not want to over-train yourself, so make sure you rest between 120-180 seconds between the sets.

man holding a weight

Smaller Number Of Reps

The training with a smaller number of reps logically asks for heavier weights in the sets, since training with smaller weights would be a complete waste of time. Even though the reps are the key parameter in the workout, you have to make sure all the rest parameters are adequate.

As we already mentioned earlier, our goal is hypertrophy and especially the hypertrophy of those muscle fibres that have the largest growth potential.

We talked about two types of muscle fibre type I and type IIA but those muscle fibres do not have a high growth potential like muscle fibres type IIB from the group of fast muscle fibre.

Fibres type IIA have a larger growth potential than fibres type I. There are also type IIC muscle fibres but they are really insignificant in this case since their share in the muscles is minor.

We came to conclusion that the fibres type IIB are exactly those that we need to help us reach our goal and that is the growth of muscle mass.

But that is not that easy to do. It is very difficult activating these fibres and you need specific parameters. That raises the question: which is the number of reps and what are the rest of the parameters that influence the activation of these fibres?

The answer is: smaller number of reps, more sets and heavier weights. These are all the parameters you should stick with to activate the muscle fibre type IIB (first number are sets, second number are reps):

– 12×2 with the weight you can lift 5 times

– 10×3 with the weight you can lift 6 times

– 6×5 with the weight you can lift 8 times

When it comes to the rest between sets, it should last between sixty and ninety seconds.

If it is difficult for you to determine the weights that you can lift a certain number of reps, we prepared a little table for you to help you out.

100% = 1RM

95% = 2RM

90% = 4RM

85% = 6RM

80% = 8RM

75% = 10RM

65% = 15RM

60% = 18-20RM

55% = 24RM

40% = 34RM

30% = 50RM

We gave you just a few parameters and advice that can help you plan your training program. One more very important thing, constantly change the exercises in your workout since your body adapts to changes so it would be the best to change the parameters and exercises each month.