Cluster sets can help one perform more training volume, maintain greater bar speed and also achieve significant strength gains at a lower perceived effort. But how do they affect one’s ability to predict repetitions in reserve?
What did they test? The authors looked at how training using cluster sets affects one’s ability to predict repetitions in reserve and how they compare to traditional sets.
What did they find? There were no differences between cluster and traditional sets for repetitions in reserve prediction accuracy, although the design of the study somewhat limits what we can take from it.
What does it mean for you? Cluster sets are probably not going to heavily affect your ability to predict repetitions in reserve but it’s still advisable to calibrate your ability to accurately predict repetitions in reserve to ensure you’re not leaving gains on the table.
What’s the Problem?
As you can probably tell by this issue's cover article, estimating repetitions in reserve (RIR) is a valuable skill that can be critical in one’s ability to train effectively, especially when training for muscle growth where close proximities to failure are needed to maximize adaptations. Previous studies 1, some of which we have also reviewed in REPS 2, have shown that, on average, both trained and untrained individuals are relatively good at gauging their proximity to failure. However, the limitations of said studies, e.g.: acute training design, don’t necessarily allow us to assume that everyone will be perfectly accurate in estimating their proximity to failure, something that, as a coach, I often see with athletes of all levels and sporting backgrounds.
Just to be fully transparent here, I am one of the authors of both the “Accuracy in predicting repetitions to task failure in resistance exercise: a scoping review and exploratory meta-analysis” and the ““Just One More Rep!” – Ability to Predict Proximity to Task Failure in Resistance Trained Persons” papers, so there’s no inherent bias in me treating the findings of those studies with caution. Rather, the critical interpretation of the research should be among the core values of anyone who claims to be evidence-based and is also one of the main reasons why REPS is a valuable resource for those looking to stay up-to-date with the literature.
My disclaimers aside, finding ways to improve RIR prediction accuracy can be a potential game changer for muscle gains, regardless of the proximity to failure you want to train at.
When lifting weights, a traditional set involves performing a specific amount of repetitions until a specific proximity to failure is achieved, where the set is terminated. However, cluster sets are another way to structure your sets, which involve taking short breaks within each set. Cluster sets may allow one to maintain or even increase their repetition speed and power compared to traditional sets 3. However, the current literature shows that this may not always be the case 4. However, cluster sets may allow one to perform more training volume than when performing traditional sets, allowing cluster sets to be used as an advanced training technique when trying to maximize adaptations 4. Previous research has also shown that cluster sets can lead to similar strength gains as traditional sets but at lower perceived efforts 5, as well as lead to “improved” technique 3, making cluster set training an excellent tool for strength training.
Usually, and when training with traditional sets, as you get closer to failure, the fatigue build-up will cause your reps to slow down significantly, potentially making gauging RIR easier than with cluster sets. During cluster sets, the within-set rest may mask your ability to accurately predict RIR, especially since in some cases cluster sets can allow one to maintain a higher repetition speed versus traditional sets.