What Are Cluster Sets?

Cluster sets are a method of structuring lifts so that reps are grouped into small "mini-sets" (or clusters), each separated by brief rest (typically 15-30 seconds) between every 2-5 reps. This allows high-intent rep execution while minimising fatigue-induced performance drop-off (Roberts, 2023).

So, instead of grinding out six consecutive squats, you might rack the bar after two reps, rest 20 seconds, do another two, and so on. You still rest between full sets as usual, but the short breaks inside sets are the hallmark of cluster programming (Davies et al., 2021).

Why Cluster Sets Are Used

1. Maintain Power & Velocity

Cluster sets help preserve bar speed, force output, and power across all reps, especially when using heavy loads (80–90% 1RM). Traditional sets often see a decline in output as fatigue accumulates (Tufano et al., 2017; Haff et al., 2003).

2. Strength & Athletic Performance

Meta-analyses report that cluster sets produce equivalent strength gains to traditional sets while also offering superior improvements in high-velocity (explosive) strength and your rate of force development (Davies et al., 2021; Orange et al., 2020).

3. Managing Fatigue

Cluster sets reduce perceived exertion and physiological fatigue, allowing for a more consistent performance. They appear to minimise central nervous system fatigue and maintain higher levels of motor unit recruitment across a set (Hiscock et al., 2018; Tufano et al., 2016).

Performance & Hypertrophy

Strength & Hypertrophy

Cluster sets are comparably effective to traditional sets for increasing both strength and muscle hypertrophy. A systematic review concluded that when total training volume is matched, strength and size gains are similar between cluster and traditional models (Davies et al., 2021). However, traditional sets may elicit slightly more metabolic stress, which can contribute to hypertrophy under some conditions (Beardsley, 2022).

Post-Activation Performance Enhancement

Dello Iacono et al. (2016) found that cluster set protocols showed better post-activation potentiation (PAP) responses (short-term enhancement of muscle force or power output) than traditional sets in professional basketball players. Participants retained a greater average propulsive power and showed improved countermovement jump (CMJ) height post-exercise.

Fatigue Management and Technique

Research suggests cluster sets limit calcium-ion interference and neuromuscular fatigue, preserving muscle fiber tension and maintaining movement quality (Hiscock et al., 2018). Additionally, lifters report lower session RPEs and fewer breakdowns in form compared to traditional volume-matched protocols (Tufano et al., 2016).

Cluster Sets vs Traditional Sets:

Goal / Metric	Traditional Sets	Cluster Sets
Power & velocity during set	Declines across reps	Maintained throughout
Strength gains	Equally effective	Equally effective
Muscle hypertrophy	Effective via metabolic stress	Similar with less fatigue
Perceived effort & fatigue	Higher fatigue & RPE	Lower fatigue, better recovery
Technique consistency	Declines as reps progress	Better maintained
Time efficiency	Shorter sets, less rest	Longer total session time

How to Use Cluster Sets

When you may choose to use cluster sets:

• For heavy compound lifts: squats, deadlifts, bench press, cleans.

• During strength or power phases.

• If you're using velocity-based training (VBT) tools or tracking bar speed.

• When technique under load or recovery is a priority.

Example Use Cases:

1. Max Strength: 3 sets of 6 reps (2+2+2) with 20s intra-set rest at 85-90% 1RM (Tufano et al., 2016).

2. Power Training: 5 sets of 3 single reps with 15s rest between each rep at 70% 1RM (Haff et al., 2003).

3. Hypertrophy Focused: 4 sets of 12 reps broken into 3×4 with 20s rest between clusters at 60-70% 1RM (Beardsley, 2022).

   
   

Summary

Cluster sets are a practical method for varying how you train, helping to reduce fatigue, preserve power, and maximise rep quality; particularly during strength and power training. While traditional sets remain valuable for hypertrophy and metabolic stress, cluster sets offer an alternative for athletes or lifters managing heavy loads or movements centred on technique.

References

1. Beardsley, C. (2022). How might cluster set training work for hypertrophy? Medium. https://sandcresearch.medium.com

2. Davies, T., Orr, R., Halaki, M., & Hackett, D. (2021). Effect of cluster set configurations on mechanical, perceptual, and physiological responses to resistance training: A systematic review and meta-analysis. Sports Medicine, 51(9), 1941–1963. https://doi.org/10.1007/s40279-021-01455-3

3. Dello Iacono, A., Beato, M., & Halperin, I. (2016). The effects of cluster-set and traditional-set postactivation potentiation protocols on vertical jump performance. International Journal of Sports Physiology and Performance, 11(5), 630–636. https://doi.org/10.1123/ijspp.2015-0414

4. Haff, G. G., Hobbs, R. T., Haff, E. E., Sands, W. A., Pierce, K. C., & Stone, M. H. (2003). Cluster training: A novel method for introducing training variation. Strength and Conditioning Journal, 25(6), 18–24. https://doi.org/10.1519/00126548-200312000-00004

5. Hiscock, D. J., Dawson, B., & Peeling, P. (2018). Cluster training: A novel method for introducing training variation. Journal of Strength and Conditioning Research, 32(3), 674–682. https://doi.org/10.1519/JSC.0000000000001858

6. Orange, S. T., Metcalfe, J. W., Marshall, P., & Vince, R. V. (2020). The effects of cluster set resistance training on neuromuscular performance: A systematic review and meta-analysis. European Journal of Sport Science, 20(2), 164–174. https://doi.org/10.1080/17461391.2019.1622541

7. Roberts, C. (2023). Cluster sets. Science for Sport. https://www.scienceforsport.com/cluster-sets

8. Tufano, J. J., Brown, L. E., & Haff, G. G. (2016). Theoretical and practical aspects of different cluster set structures: A systematic review. Journal of Strength and Conditioning Research, 31(3), 848–867. https://doi.org/10.1519/JSC.0000000000001510

9. Tufano, J. J., et al. (2017). Maintaining power with cluster sets. Strength and Conditioning Journal, 39(3), 20–33. https://doi.org/10.1519/SSC.0000000000000290