Cluster Training: What Is It?

Although it's not very well known, cluster training is a variety of the conventional series and repetitions training method. This version improves power and starting speed.
Cluster Training: What Is It?

Last update: 24 July, 2021

Most people use a training method based on series and repetitions. This is the most common, especially if you only want to be in shape because you want to develop muscle hypertrophy. However, it’s not the only method. Variants like cluster training are becoming increasingly more popular.

Also known as conglomerate training, this method is a way of dealing with series and repetitions using the intervals as a reference point. The rest time is more important than how quickly you finish a set. Discover what cluster training is and how you can use it!

What is cluster training based on?

In order to understand what cluster training is, you have to consider its differences in respect to more traditional training methods. When you work out with weights, you use series that incorporate a limited number of repetitions. Within each series, you’ll have a period of rest.

Cluster training maintains the philosophy of working with series and repetitions, but this time you won’t rest between each set. Here you’ll rest in the middle of the reps.

We could say that, in this sense, cluster training is based on seconds of intervals for each rep. When doing it, you won’t do 6, 8, or 12 reps on one side, you’ll include a pause of 10 to 20 seconds whilst you complete the series.

Extensive cluster training

This consists of doing 5-6 series of 5-6 repetitions with a rest time of 10 seconds between each rep. This means that you’ll start a series by completing a movement, you’ll rest for 10 seconds, you’ll do the second movement, you’ll rest for 10 seconds, etc until you complete your repetitions.

This kind of variant helps you develop muscular hypertrophy, but in a way that’s different to how the majority of people do it. Extensive cluster training uses the concept of maximum repetitions (RM), or the most weight you can manage in one movement, as a model.

In optimum hypertrophy training, you’ll do an average of 3 series of 3 reps with your RM, for a total of 9 reps. Using this method, thanks to the rest times, you can do between 25 and 36 reps, which has a positive effect on your muscle growth.

Cluster training.
Cluster training changes the way you rest, which may be useful for muscular hypertrophy.

Intensive cluster training

You can do this by doing 5-6 series of only 1 or 2 repetitions. This is a way to implement a 20-second rest between each repetition, in a way that allows you a larger interval for muscle recuperation. For this reason, you can increase the percentage of your RM for each exercise.

We recommend this style, to start with, to obtain better strength and power. Thanks to lifting a heavier weight, you train your muscles so they become stronger. Athletes whose disciplines require explosive force often use this style of training. 100-meter sprinters, for example, tend to practice it.

The spectrum of series and repetitions is an example of how you can implement cluster training. Of course, you can modify these according to your sensations, objectives, and physical condition.  However, it’s important to ensure you actually rest for the whole rest time between each rep.

What are the benefits?

Depending on which method you use, you’ll receive one benefit or another. Generating muscular hypertrophy and getting stronger are two clear advantages when it comes to starting to train using this method. The best of all is that you can use the intensive or extensive version in the same session.

Specialists developed cluster training from the concept of muscular failure. This is where you reach the limit of resistance that your muscles can support when working out. For some, muscular failure means reducing the weight when lifting certain objects or an obstacle that they recover from by adding times of rest.

Roughly, the main benefits of including this method in your routine are the following:

  • Overcoming periods of stalemate where you’re unable to advance for a few weeks
  • Improving your strength and, with it, being able to lift more weight in a shorter time
  • Larger muscular gains if you chose the extensive variety
  • Improving your starting strength of each rep
  • Perfecting the technique you use for each movement
  • Your muscles recuperate more efficiently

It’s important to remember that we don’t recommend this kind of training for everyone. To start with, those that practice it should have some experience in lifting weights, have some muscular base, and have clear objectives.

Neither do we recommend that you use it in every gym session. You should combine your conventional routines of series and repetitions in a way that allows you to distribute it throughout the week with specific days for each one.

woman training but also having a quick rest weight training
It’s important to combine cluster training with other more conventional styles of series and repetitions.

What does the research say about it?

One of the first investigations into this kind of training was published in 2008. The study shows that a rest of 10-30 seconds between every repetition has a special impact on the development of strength and power.

The period of rest allows the muscles to partially recuperate in cluster training. This brief recovery distributes the force you would use to move the bar, so that you use your energy to lift a greater amount of weight in each repetition, based on your RM.

The interval of time is supposed to replenish phosphocreatine, which you don’t get in more conventional repetitions. This causes a greater accumulation of lactic acid as muscle glycogen is consumed.

There are also investigations that demonstrate how useful it is when it comes to high-velocity resistance training, as well as studies that suggest positive effects when increasing your strength compared to the conventional series and repetitions method.

Specialists are yet to investigate the contributions of this method when it comes to muscular hypertrophy, although many athletes vouch for its effectiveness. To summarize, it’s a variant that you should try, regardless of whether you intend to benefit from its advantages in your specific condition.

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