Reaction time (RT) is a widely used measure for testing physical performance in motor tasks. This study focused on assessing the processing speed in athletes. Twenty-five healthy volunteers were assigned to the control (n = 16) or athletes groups (n = 9). They were evaluated during motor reaction tasks based on visual stimuli and three difficulty conditions. Physiological measures were obtained from motion capture and electromyography recordings of several muscles. Two RT phases, decision-making (DMK) and electromechanical delay (EMD), were used to analyze the processing speed. The results show significant RT differences between groups. The athletes were ~30% faster compared to the control group. Despite the fact that all participants were right-handed, RT did not show any differences between hands performances in any group. However, DMK time revealed significant differences between the hands. Controls showed a longer DMK time for the right-hand election, ~20% more than the left, while athletes showed no such disparity. These findings reveal that quantifying the decision-making component of reaction time is crucial to assessing processing speed in sport. This approach could facilitate the monitoring of adaptations in both motor–cognitive and neuromuscular processes. The theoretical implications presented in this study offer perspectives on handedness research.

This pilot study investigates the relationship between gesture intuitiveness and muscle network efficiency in human–machine interactions (HMIs), emphasizing objective neurophysiological measures. EMG signals from 16 muscles were analyzed to construct muscle networks based on synergies derived from non-negative matrix factorization (NMF) and intermuscular coherence (IMC) across three frequency bands. Metrics such as weighted global efficiency (WGE) and effective average strength (EAS) were correlated with gesture intuitiveness levels. Preliminary results suggest that WGE and EAS in synergy-based muscle networks, particularly in the Gamma 1 band, may be associated with perceived gesture intuitiveness (p = 0.10 and 0.05, respectively). These findings suggest the potential utility of neurophysiological metrics to support the assessment of intuitive gestures, warranting further investigation with broader samples.

Subjects with low back pain (LBP) have shown different responses to fatigue compared to healthy individuals. The aim of this study was to analyze and compare the connectivity of the multifidus muscles using intermuscular coherence (IMC) in a squat protocol between healthy subjects and a subject with a history of low back pain. The protocol consisted of three sets of squats, with the final set performed with as many repetitions as possible to induce muscular fatigue. The findings indicated that IMC decreased among healthy subjects during the last repetitions of the squat series, with percentage changes in connectivity (CC) ranging from approximately 43.3% to 67.3% when comparing the first and last 10 repetitions. In contrast, the subject with a history of low back pain (LBP) exhibited an opposite trend, showing a 41.8% increase in IMC. These results suggest a different response of IMC to fatigue related to LBP. This also establishes IMC as a potentially useful tool for characterizing fatigue and LBP during physical exercise.