Building muscle requires a successful combination of strength work, proper diet, and rest after exercise. If this is your goal, you also want to know how fast you should do the repetitions to get better results in less time.

The issue of whether slow or fast reps are more effective in achieving muscle development is a constant debate in the world of fitness and bodybuilding. There are different theories for a simple reason: no two bodies are the same and getting your muscles to grow will not only depend on the speed at which you perform the repetitions but on other determining factors such as your own genetics, your hormonal system or the ease that you may have to achieve an optimal recovery that favors the development of your muscles.

On the other hand, strength training not only pursues muscles with more volume, but also more powerful and with greater resistance. Achieving all three goals – strength, endurance, and volume – requires a well-planned training program that takes into account four determining factors:

  • The speed of repetitions, slow or fast.
  • The load with which they are carried, because a greater weight implies greater resistance.
  • The number of series, which is what marks the mechanical work and the possible exhaustion (hypertrophy) of the muscle.
  • The rest periods. Remember that good recovery is essential for muscle growth. Muscles don’t actually grow when they’re working hard, but when they’re resting.

Correctly combining these four aspects of strength training is the key to growth for your muscles.

How fast to do the repetitions to gain muscle?

There are no hard and fast rules, but knowing how the speed of repetitions influences muscle growth will help you decide what is best to achieve your goal

The rapid repetitions involve explosive force and continued work fast contractions, usually with low weight, which will make you gain strength. On the other hand, the slow ones prolong the effort and suppose that the muscle will be in tension for a longer time and will require the arrival of a greater blood flow (oxygen) to be able to maintain it, especially if the repetitions are carried out with a moderate-high load. They are ideal if you want to gain power.

In both cases, the objective is to achieve muscle hypertrophy, that moment in which the muscle, after the work done, begins to reinforce its own fibers and create new microfibers. The result: increased growth and volume.

Choosing between fast or slow reps to gain muscle depends on your own fitness and training level. Your coach should always be the one to guide you on the optimal formula to grow your muscle mass while avoiding any risk of injury. Most professionals agree that the ideal is to combine both speeds to take advantage of the benefits provided by each of them. To do this you can do different types of training, for example:

  1. Fast reps. Strength training two days a week doing 3-4 sets of 8-12 reps at a light pace with medium loads. This option requires that your muscles have a good general condition, with sufficient internal strength, to avoid damaging the fibers and ending up with an injury that prevents progress in their development.
  2. Slow reps. I strength train one day a week, focusing on exercises that involve the large muscle groups and choosing a high load but always in proportion to your own body weight. A good session would be one that includes 2 – 3 series, of 5 slow repetitions, which involve keeping the muscles in tension for at least 8 seconds, of exercises such as bench press, squats, deadlifts or dips, among others.
  3. Combine both workouts, focusing one day on fast reps and another on slow ones.

As you can see, the best way to gain muscle mass is to vary the speed of the repetitions to obtain the maximum performance of your muscles and achieve more resistant fibers and with more volume, something that would be unthinkable without adequate rest and without a diet in the the essential protein is not lacking.