Supersets (the completion of two exercises consecutively followed by a recovery period) and trisets (the completion of three exercises consecutively followed by a recovery period) may be an efficient use of time while producing results. But a recent study shows that with efficiency, also comes changes in muscle damage and in-session lactate concentrations. The study by Weakley, J.J.S., Till, K., Read, D.B. et al. concluded that increases in metabolic measures occur simultaneously with reductions in neuromuscular performance 24 hours after training--which points to a greater fatigue response. In comparison, traditional resistance training induced a smaller neuroendocrine stress response immediately and 24 h after training.
What does this mean for you? The results of this study indicate that utilizing SUPERs is beneficial when time is short or when other training goals require increased training time (e.g., skill development). Also, SUPERs can be used as a form of metabolic conditioning when an improvement in total training capacity is desired. However, because of the increased fatigue response, building in recovery is vital. Fitness professionals may wish to place SUPERs at the beginning of the training week to assist in the management of fatigue, and traditional resistance training protocols towards the latter half of the training week.
Weakley, J.J.S., Till, K., Read, D.B. et al. Eur J Appl Physiol (2018) 117: 1877.