ABSTRACT
Morales-Artacho, AJ, García-Ramos, A, Pérez-Castilla, A, Padial, P, Gomez, AM, Peinado, AM, Pérez-Córdoba, JL, and Feriche, B. Muscle activation during power-oriented resistance training: continuous vs. cluster set configurations. J Strength Cond Res 33(7S): S95-S102, 2019-This study examined performance and electromyography (EMG) changes during a power training protocol comprising continuous or clustered set configurations. Eighteen active males completed 6 sets of 6 repetitions during the loaded (20% 1 repetition maximum) countermovement jump (CMJ) exercise, continuously (n = 9) or with a 30-second pause every 2 repetitions (cluster; n = 9). Power output, vastus lateralis (VL), vastus medialis (VM), and rectus femoris (RF) EMG were recorded during all CMJs. Relative changes from the first repetition were assessed on the EMG root mean square (RMS), median frequency (Fmed), and a low- to high-frequency ratio index of fatigue (FInsmk). Greater power output decrements were observed during the continuous set configuration (p = 0.001, (Equation is included in full-text article.)< 0.01). Greater RMS increments in VL (6.8 ± 11.3 vs. -1.7 ± 5.8%) and RF (9.3 ± 14.2 vs. 1.9 ± 6.9%), but not VM (2.0 ± 4.7 vs. 2.6 ± 7.3%), were also observed in the continuous compared with the cluster sets (p = 0.033, (Equation is included in full-text article.)= 0.06). Progressive decrements in Fmed and increments in FInsmk were observed across repetitions in both set configurations. In conclusion, although clustering sets between repetitions clearly maintained power output, mixed responses were observed on the examined EMG parameters.
Subject(s)
Muscle Fatigue , Quadriceps Muscle/physiology , Resistance Training/methods , Weight Lifting/physiology , Adult , Electromyography , Humans , Male , Muscle Strength , Young AdultABSTRACT
Most of the algorithms used for information extraction and for processing the amino acid chains that make up proteins treat them as symbolic chains. Fewer algorithms exploit signal processing techniques that require a numerical representation of amino acid chains. However, these algorithms are very powerful for extracting regularities that cannot be detected when working with a symbolic chain, which may be important for understanding the biological meaning of a sequence or in classification tasks. In this study, a new mathematical representation of amino acid chains is proposed, which is derived using a similarity measure based on the PAM250 amino acid substitution matrix and that generates 20 signals for each protein sequence. Using this representation 20 consensus spectra for a protein family are determined and the relevance of the frequency peaks is established, obtaining a group of significant frequency peaks that manifest common periodicities of the amino acid sequences that belong to a protein family. We also show that the proposed representation in 20 signals can be integrated into Chou's pseudo amino acid composition (PseAAC) and constitute a useful alternative to amino acid physicochemical properties in Chou's PseAAC.