For decades, bodybuilders, weightlifters and powerlifters have searched for the best training systems. What is inseparably linked with this issue is a choice of weight (% of ML that is your maximum load), and a number of repetitions. As if that was not enough, a certain weight and number of rep also determine your breaks.

If you lift weight within the range of 95-100% of your maximum, you won't be able to shorten the rest between each sets. Your break can be 3-5 minutes, while in the range of 60-80% of the maximum it is possible to shorten it to 45-60 seconds. Coming back to the main thread, at many gyms you can learn that in order to gain mass you shoud do 8-15 reps, to gain strength: 1-3 reps, and to sculpt your body: 15-30. It is a blatant simplification which does not reflected reality. Why?

What determines muscle growth?

You should remember that weight increase does not have to be associated in any way with muscle growth. Why? You can drink a litre of water, you can take creatine a few days, you can take flavoring SAA; all of these are examples of typical situations when body weight is increasing, but it does not necessarily have to translate directly to more muscles. Muscles will saturate with glycogen - after several days of carbohydrates restrictions. Once again, weight is growing but muscles - not necessarily. Increase in muscle mass depends mostly on a diet with caloric surplus. Even the best hypertrophic training wil turn out ineffective if you don't ensure the right amount of protein, carbohydrates and fats. Suppose that you eat well, train hard, but ... do not get enought sleep, and, to make matters worse, work in shifts. How will your muscle growth and desire to train look like? My answer is: usually badly. In the same way, you can do 1-3 repetitions for 30 years, but you will not increase your strength if you don't choose appropriate training. Is it possible to build up power on isolated biceps and triceps exercises, forgetting about leg training (which is characteristic of prevalent gym goers)? Without squats, deadlift, clean and jerk, pull-ups or rowing? Exactly: it's not that simple. And it's the same with the "magic" range of 15-30 repetitions per set, which is believed to "define" your figure. Usually such "sculpting" turns out to have no effect whatsoever. Why? Because you have forgotten about a diet (caloric deficit), aerobic training (eg. running, swimming), interval training (eg. sprints, weight dragging), and finally about "buners". 15-30 repetitions of an exercise, especially isolated one, has minimal effect on your body.

Is a large number of reps not suitable for building muscle mass?

Paradoxically, in many exercises the scope of 15-30 reps is ideal for... hypertrophy! For exmple in: leg press on the machine, shoulder press, wide grip push press (while sitting), climbing on your toes, lying barbell extensions, tricep push downs.

Watch JESSE MARUNDE (RIP) squat 20 times with 185 kg:


Many bodybuilders, weightlifters and strongmen take what they can from high-rep range, eg. in squats:

  • late Jesse Marunde - 20 squats with the weight of 185 kg,
  • 23 squats with the weight of 227 kg of legendary Tom Platz,
  • Sergio Oliva - he does 3 sets with 20 reps,
  • Mikhail Koklyaev does high-reps squats with huge weight (also with weight lessening).

Incorrect thinking about a number of repetitions lies in a misunderstanding of the issue of muscle fibers proportions. For example, biceps of thigh can contain up to 65-85% of red fibers [2], which makes the optimal range of repetitions for hypertrophy much further than most people think. Similarly deltop (shoulder) muscles can in up to 88% be composed of red fibers, which makes it ideal for the hypertrophic scope of 15-30 reps! When it comes to squats, each head of quadriceps fermoris has different proportions of muscle fibers. This means that to fully overtrain your thighs, you should apply a number of reps that will stimulate not only quick (3-6) and intermediate fibers (6-8), but also slow, red (15-30). In turn, in circuit and stationary training you can work perfectly well on your shape doing 4-6 reps (eg. in ACT training) because a similar effort works more as a metabolic stimulant.

Does tempo have any importance?

Let's look closed at another factor: TEMPO.

Do 10 bench presses (with reserves for 3-4 reps) as quickly as you can. On the next workout try to slow down the negative phase (lowering the weight to your chest) to 3 seconds in each repetition, and stop for 2 seconds on the chest. As you can see, you extend each repetition at least 5 seconds. On a scale of 10 repetitions it means increase of time under tension to about 50 seconds. As you can see, the pace has a gigantic impact on the TUT. In terms of hypertrophy, such slowdown in the negative phase of the movement saves a lot of precious minutes at the gym. Instead of doing 20 reps carelessly and quickly, you may realise you're exhausted already after the first 6-8!