Music alters heart rate and psychological responses but not muscle activation during light-intensity isometric exercise

Listening to music manipulates attention to be more externally focused, which has the potential to improve muscular efficiency. This study aimed to determine the effect of listening to music on muscle activation during an isometric exercise task, and compare this effect to those of other attentional focus conditions. Apparently healthy subjects (n = ​35; 16 men/19 women) completed an isometric elbow flexion task for 1 ​min in three randomized and counterbalanced conditions: internal focus (INT), external focus with a simple distraction task (EXT), or listening to music (MUS). Muscle activation of the biceps and triceps brachii and heart rate (HR) were recorded throughout the exercise tasks. Ratings of perceived exertion (RPE), affective valence, and motivation were measured at the end of each trial. There was no difference in muscle activation measures among the three conditions. HR during MUS was lower than EXT at 15 ​s ([89.4 ​± ​11.8] beats/min vs. [93.1 ​± ​12.9] beats/min; p ​= ​0.018) and 30 ​s ([90.6 ​± ​12.4] beats/min vs. [94.2 ​± ​12.5] beats/min; p ​= ​0.026), and lower than INT at 60 ​s ([93.3 ​± ​13.3] beats/min vs. [96.7 ​± ​12.0] beats/min; p ​= ​0.016). Overall RPE was higher for INT (13.4 ​± ​2.2) than for MUS ([12.6 ​± ​2.0]; p ​= ​0.020) and EXT ([11.94 ​± ​2.22]; p ​