This randomized crossover trial compared two resistance exercise methods in six strength-trained individuals. Participants performed back squats using either cluster sets or traditional sets. The cluster set method involved 30-second rest intervals after the second and fourth repetitions, while the traditional set used continuous repetitions without extra breaks.
Researchers measured barbell velocity loss, oxygen uptake, blood lactate, and energy system engagement. They found that cluster sets resulted in better preservation of barbell velocity compared to traditional sets. Additionally, blood lactate concentrations were lower with cluster sets, and the metabolic pattern showed a higher alactic component and lower lactic component.
No adverse events or safety concerns were reported during this acute study. However, the study had a very small sample size of only six people. Readers should be careful not to generalize these results to non-strength-trained individuals or to exercises other than the back squat. This trial suggests set structure can influence the acute physiological and performance profile of resistance exercise.