Tired of grinding it out in the gym with the same old uninspired training splits and set/rep schemes? Try cluster training, and start packing on some muscle mass.

Cluster sets are an obscure training technique. You won’t find too many articles on cluster sets clogging up bodybuilding websites or forums. And what information you do locate often ties in with powerlifting, and not bodybuilding.

The aim of this article is to lay out basic cluster set usage for the natural bodybuilder. I will provide you with some sample rep and set schemes, and get you on the path to greater muscle mass.

Cluster Sets 101

What are cluster sets? Cluster sets are generally low-rep sets separated by rest-pause periods that cumulatively wear down and tax a targeted muscle. Cluster sets are not performed to failure, but become extremely intense as the number of total sets you perform increases.

For simplicity sake, I will provide an example of the cluster set approach. Let’s look at everyone’s favorite chest builder, the bench press.

Pick a weigh that you can perform at least 10 repetitions with. Now, perform only 4 reps. Rack the weight, wait 15 seconds, and knock out 4 more reps. Continue this pattern until you hit 10 total sets (40 total reps), or until you train to failure (or near failure).

This is a cluster set. You can perform a cluster set with any number of reps, and any number of sets. You can also modify rest-pause times to fit your needs and training style. I recommend sticking with a 15 to 60 second rest-pause period between each cluster set. For some extremely taxing exercises, such as squats and deadlifts, it may be necessary to expand rest periods up to 120 seconds of rest between sets.

Cluster Set Progression

For bodybuilders, cluster sets need to be performed with a focus on weight progression. You want an increasing load. The best way to do this is to shoot for a given number of reps, and when you hit this rep total, move up in weight during your next workout.

For example...let’s say you decide that for bicep curls, you want to try for 8 sets of 4 reps using the cluster set method. You choose an appropriate weight, and start hammering out reps. Let's say that for today’s workout, your set/rep total looked like this:

Leg Extensions

I recommend easing yourself into this training approach. Learn how your body reacts to cluster training before you go and hammer each body part into oblivion.

You performed 8 total sets, but couldn’t complete 4 reps on every set. You may or may not have trained to failure on the last 3 sets. I recommend avoiding training to failure, but the choice is a personal one and up to you.

Continue to use 90 pounds on subsequent bicep workout days until you can perform 8 sets of 4 reps. Then, the next time in the gym, bump your weight up to 95 pounds. This is a simple, and effective progression strategy that will pack on muscle mass without the need to add in endless number of high intensity training techniques.

Sample Cluster Set Protocols

As I stated previously, you can pretty much use any rep and set scheme when utilizing cluster sets. The following examples are just that – examples. Use them as a springboard. Experiment and tweak.

I recommend easing yourself into this training approach. Learn how your body reacts to cluster training before you go and hammer each body part into oblivion. You want to make sure you’ve avoiding over-training and excessive muscle soreness.

10x4 Cluster Set Training

The 10x4 cluster set approach involves 10 sets of 4 reps. Rest 15-60 seconds between each set. There is no need to train to failure. As mentioned, when you can perform 10 sets with 4 reps, add more weight to the bar.

The 10x4 is a good starting approach for major muscle groups such as the chest, back, and shoulders. If you find that the 10x4 is not providing a sufficient amount of work to blast a muscle, you may want to bump the reps to 5, or even 6 per set.

8x3 Cluster Set Training

For heavy, extremely taxing compound movements such as the squat or deadlift, I recommend starting with an 8x3 cluster set approach. It is also recommended that you bump your rest-pause periods to 30 to 120 seconds between sets.

Cluster set training with squats and deadlifts tend to heavily tax the lower back, especially in the latter sets. If you find that your lower back is getting over-worked, consider switching to an 8x2 or 10x2 cluster set approach.

6x6 Cluster Set Training

For smaller muscle groups, I prefer to use fewer sets and more reps. These muscle groups include biceps, triceps, traps, and could also include hamstrings. You can also use the 6x6 protocol for isolation-style movements such as leg extensions, flyes, or side laterals.

The 6x6 approach is handy for those of you that like to incorporate more movements into each workout. You could also cut the 6x6 back to a 5x6 or 5x5.

Sample Cluster Set Workout

For the sample cluster set workout, I am using a 4-day split. The split breaks down as follows:

  • Day 1… Chest and Triceps
  • Day 2… Back and Biceps
  • Day 3… OFF
  • Day 4… OFF
  • Day 5… Shoulders and Traps
  • Day 6… Legs
  • Day 7… OFF
Day 1: Chest and Triceps
  • Bench Press, 10x4 Cluster Set
  • Incline DB Press or Incline Barbell Press, 6x6 Cluster Set
  • Pec Dec or Flyes, 6x6 Cluster Set
  • Skullcrushers, 6x6 Cluster Set
  • Overhead DB Extensions, 6x6 Cluster Set
Day 2: Back and Biceps
  • Deadlift, 8x3 Cluster Set
  • BB Rows or Yates Row, 8x5 Cluster Set
  • Pullups or Pulldowns, 6x6 Cluster Set
  • DB or BB Curls, 8x5 Cluster Set
  • Hammer Curls, 5x6 Cluster Set
Day 5: Shoulders and Traps
  • Seated DB or BB Press, 10x4 Cluster Set
  • Arnold Press or Front laterals, 6x6 Cluster Set
  • Upright Rows or Side Laterals, 6x6 Cluster Set
  • DB or BB Shrugs, 10x6 Cluster Set
Day 6: Legs
  • Squats, 8x4 Cluster Set
  • Front Squats or Leg Extensions, 6x6 Cluster Set
  • Hamstring Curls or Romanian Deadlifts, 8x6 Cluster Set
  • Seated or Standing Calf Raises, 8x10 Cluster Set

Final Notes

Even though I provided an entire routine based on cluster set training, it is not necessary to base all exercises on this technique. You could simply bolster an already quality routine with a cluster set exercise, or inject a cluster set day into a stagnating routine to shock your muscles.

Get creative, learn your body, and find ways to work in cluster sets.

Posted on: Sun, 07/27/2014 - 04:00

Hi Steve.
If i wanted to incorporate cluster sets to a 2 day split (working each muscle twice a week), how would you recormend structuring it?
Would it be a good idea to do cluster sets in one workout and "ordinary" muscle training on the opposite day? Thought about only doing cluster sets on the first compound excise follow by an excise performing 3x8-12. Here is an example for chest day 1: bench press (cluster) and 2-3x8-12 DB incline press (or is the cluster sets enough?). Chest day 2: BB Incline press 3x8-12 and DB bench press 3x8-12. For biceps day 1: BB curl (cluster) and day 2: DB curl 3x10-12.Could this work or is it to taxing for the muscles?

Thank you.

Posted on: Fri, 10/25/2013 - 17:05

Isnt this very similar to density training? A target number of reps in a certain amount of time or sets?

Lewis Gordon
Posted on: Wed, 11/14/2012 - 13:39

I'm currently trying this and have tried a few of your other routines, what do you think is the best for gaining muscle?

Posted on: Mon, 09/17/2012 - 02:51

Is cluster training beneficial when cutting?

M&S Team Badge
Posted on: Mon, 09/17/2012 - 14:35

When cutting you want to continue to lift heavy weight and push yourself. This will encourage your body to retain muscle mass. With this in mind, any program can be helpful as long as you are training properly.

Nick Bennett
Posted on: Thu, 05/03/2012 - 10:04

I used cluster sets for my shoulders and triceps today, injected the method into my routine I was using and it's great, feeling it already. Considering using the routine set out above though as I've been on this one for about 6weeks.

Darrell Robinson
Posted on: Wed, 04/04/2012 - 15:04

I have recently lost 47 lbs to get to 235 from 282. I did a lot of cardio as well as some weight training. I as gained a small amount of muscle as well. I am trying to get to around 190 - 195 for Air Force ROTC & general health, but I want to continue to gain muscle. I have until August 2012 to get to 195. So here are my questions Steve. Is there some way for me to continue to lose weight and still gain muscle? Also is there still a way for me to be 190 - 195 and still have my muscle and big frame? Any advice would help greatly and best of luck of accomplishing your fitness goals! Thanks again!

Posted on: Wed, 03/21/2012 - 20:33

Hi great article , as regards tempo for the cluster sets what would you advise ? Would it be different tempo for each muscle group ? Thanks alot

M&S Team Badge
Posted on: Wed, 02/10/2010 - 08:56

Cortez...If you are looking to be lean at 190 to 210 pounds, it can be done but it will take some hard work. Just how lean are you looking to be at that weight...is seeing abs a goal, or do you simply want to look muscular at 190 to 210?

Posted on: Wed, 02/10/2010 - 04:18

I've recently gained 20 pounds in the last couple of months and I really want to get back in shape. I played football for four years in high school and lifted pretty hard. I'm a freshman in college now and im inactive. I've had some major weight changes since then, in my senior year i weighed 215 pounds standing at 5'8" and i dropped to 180 then i gained weight back to 210 and now Im 230 pounds and hardly have any muscle definiton anymore, Im just fat now. I want to get big and have about 190 to 210 pounds of muscle mass but i don't know how i should do it. Should I lose all my body fat then try to build muscle or what? I've just started back trying to lift and I use Six Star Muscle supplements (only the N.O. pills and Creatine pills). Can anyone give my advice on what I should do?