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Wearable devices have been used to assess and monitor volleyball performance. Given the diversity of technologies used and the variables measured, this study aimed to synthesize and review the wearable technology used to assess and monitor physical performance in volleyball players. A comprehensive search of published articles was performed in the following databases: Web of Science, PubMed, and Scopus, up to 23 October 2022. Studies with volleyball players of any age that used a wearable device to assess or monitor physical performance (e.g., jump height) were included. Nine studies conducted with male or female volleyball players were included. The participants' age ranged between 16 and 32 years. Eight studies used Triaxial IMU, and one study used Vertec IMU. The performance analysis was based on vertical jump ability (n = 7) and overall volleyball performance (n = 2). Of the nine studies analyzed, 75% of the studies revealed blinding at the participant level and allocation concealment, and 95% reported a low risk of bias in the outcome assessment. This study shows that monitoring and assessing vertical jump ability through wearable devices is an increasing procedure in volleyball. Therefore, as jump height is a critical variable in athletic performance in volleyball, coaches and researchers might consider using wearable devices to assess and monitor physical performance changes in volleyball players. [ABSTRACT FROM AUTHOR]

Exergy efficiency, Nusselt number, friction factor, pressure drop, thermal and frictional entropy generation of water-based nanodiamond + Fe3O4 nanofluid flow in a tube and with various coiled wire inserts have been studied experimentally under turbulent and constant heat flux boundary conditions. The experiments were conducted in the Reynolds number range from 2000 to 22,000, particle concentrations of 0.05%, 0.1% and 0.2% and coiled wire inserts of different p / d values of 3.67, 2.34 and 1.00, respectively. Results indicate that at 0.2% vol. and Reynolds number of 20,095, without coiled wire inserts, the heat transfer coefficient, Nusselt number, friction factor, pressure drop and pumping power are enhanced to 44.36%, 29.55%, 11.1%, 29.58% and 39.49% over the base fluid data. Similarly, at 0.2% vol. and Reynolds number of 20,095, with coiled wire inserts of p / d = 1, the heat transfer coefficient, Nusselt number, friction factor, pressure drop and pumping power are further enhanced to 107.19%, 66.36%, 38.84, 64.44% and 76.54% over the base fluid data without inserts. The thermal entropy generation is decreased to 30.80% and it is further decreased to 46.34% at 0.2% vol. and Reynolds number of 20,095 with coiled wire inserts of p / d = 1. The exergy efficiency of water is 18.95%, and it is increased to 24.06% for 0.2% vol. and it is further increased to 51.85% for 0.2% vol. and Reynolds number of 20,095 with coiled wire inserts of p / d = 1. The study indicates that the hybrid nanofluids with coiled wire inserts are guaranteed choice for augmenting the exergy efficiency of flow through tube. [ABSTRACT FROM AUTHOR]