The practice of a musical instrument requires fine dexterity, repetitive, fast, and precise movements, as well as important efforts to set the instrument into vibration, while adopting postures often unnatural for the human body. As a result, musicians are often subject to pain and musculoskeletal disorders. In the case of plucked string instruments and especially the concert harp, the plucking force is directly related to the strings' tension. Consequently, the choice of the strings has to be made based on both, the musician feel while playing, and the musculoskeletal consequences. This paper investigates how the string properties and the playing dynamics affect the finger and wrist muscle activity during harp playing. This study first emphasized the noteworthy recruitment of the flexor and extensor muscles (42% and 29% of MVC, respectively). Findings outlined further that the fingering choice, the adopted playing dynamics and the string's material govern the muscular activity level and the playing control. Such results are a first step to better understand how the harp ergonomics may affect the player's integrity and help them decide the most suitable stringing for their practice.