Exhausting repetitive piano tasks lead to local forearm manifestation of muscle fatigue and negatively affect musical parameters.

Muscle fatigue is considered as a risk factor for developing playing-related muscular disorders among professional pianists and could affect musical performance. This study investigated in 50 pianists the effect of fatiguing repetitive piano sequences on the development of forearm muscle fatigue and on piano performance parameters. Results showed signs of myoelectric manifestation of fatigue in the 42-electromyographic bipolar electrodes positioned on the forearm to record finger and wrist flexor and extensor muscles, through a significant non-constant decrease of instantaneous median frequency during two repetitive Digital (right-hand 16-tones sequence) and Chord (right-hand chords sequence) excerpts, with extensor muscles showing greater signs of fatigue than flexor muscles. In addition, muscle fatigue negatively affected key velocity, a central feature of piano sound intensity, in both Digital and Chord excerpts, and note-events, a fundamental aspect of musicians' performance parameter, in the Chord excerpt only. This result highlights that muscle fatigue may alter differently pianists' musical performance according to the characteristics of the piece played.

Time history of upper-limb muscle activity during isolated piano keystrokes.

Playing-related musculoskeletal disorders (PRMDs) in pianists can lead to the cessation of performance-related activities. A better understanding of the impact of performance parameters on muscle activities could help improve prevention of pianists' PRMDs. The purpose of this study was to assess the effect of touch and articulation (two performance parameters) on muscle activity and to compare analysis based on scalar and time-history values. Activity of nine upper-limb muscles were recorded in 12 professional classical pianists during the performance of slow-paced isolated keystrokes using pressed and struck touch and staccato and tenuto articulation. A two-way (touch and articulation) ANOVA with repeated measures was performed on time history and single-point values of muscle activations. Pressed touch prime mover muscle was the triceps brachii while struck touch entailed progressive deactivation of anti-gravity muscles before the keystroke. Compared to tenuto articulation, staccato articulation induced a muscular burst on shoulder muscles. Our results suggest that warm-up routines aiming to prevent PRMDs should integrate different types of touch and articulation. Staccato articulation appears however to be an important risk factor of PRMDs located at the shoulder structure. Temporal analysis was a more reliable tool to interpret pianists' muscle activity during keystrokes.

Effects of Trunk Motion, Touch, and Articulation on Upper-Limb Velocities and on Joint Contribution to Endpoint Velocities During the Production of Loud Piano Tones.

Piano performance involves several levels of motor abundancy. Identification of kinematic strategies that enhance performance and reduce risks of practice-related musculoskeletal disorders (PRMD) represents an important research topic since more than half of professional pianists might suffer from PRMD during their career. Studies in biomechanics have highlighted the benefits of using proximal upper-limb joints to reduce the load on distal segments by effectively creating velocity and force at the finger-key interaction. If scientific research has documented postural and expressive features of pianists' trunk motion, there is currently a lack of scientific evidence assessing the role of trunk motion in sound production and in injury prevention. We address this gap by integrating motion of the pelvis and thorax in the analysis of both upper-limb linear velocities and joint angular contribution to endpoint velocities. Specifically, this study aims to assess kinematic features of different types of touch and articulation and the impact of trunk motion on these features. Twelve pianists performed repetitive loud and slow-paced keystrokes. They were asked to vary (i) body implication (use of trunk and upper-limb motion or use of only upper-limb motion), (ii) touch (struck touch, initiating the attack with the fingertip at a certain distance from the key surface, or pressed touch, initiating the attack with the fingertip in contact with the key surface), and (iii) articulation (staccato, short finger-key contact time, or tenuto, sustained finger-key contact time). Data were collected using a 3D motion capture system and a sound recording device. Results show that body implication, touch, and articulation modified kinematic features of loud keystrokes, which exhibited not only downward but also important forward segmental velocities (particularly in pressed touch and staccato articulation). Pelvic anterior rotation had a prominent role in the production of loud tones as it effectively contributed to creating forward linear velocities at the upper limb. The reported findings have implications for the performance, teaching, and research domains since they provide evidence of how pianists' trunk motion can actively contribute to the sound production and might not only be associated with either postural or expressive features.