An inertial measurement system, using a combination of accelerometers, gyroscopes and magnetometers, is of great interest to capture tennis movements. We have assessed the key biomechanical moments of the serve phases and events, as well as the kinematic metrics during the serve, to analyze their influence on serve speed. Eighteen male competitive tennis players, equipped with the inertial measurement units, performed a prolonged serve game consisting of 12 simulated points. Participants were divided into groups A and B in accordance with their positioning above or below the sample average serve speed. Group A (compared with their counterparts) presented with lower back hip adduction and knee flexion, and a higher leftward thoracic tilt during the impact event (−14.9 ± 6.9 vs. 13.8 ± 6.4, 2.8 ± 5.9 vs. 14.3 ± 13.0 and −28.9 ± 6.3 vs. 28.0 ± 7.3°). In addition, group A exhibited higher maximal angular velocities in the wrist and thorax, as well as a lower maximal angular velocity in the back hip than group B (427.0 ± 99.8 vs. 205.4 ± 9.7, 162.4 ± 81.7 vs. 193.5 ± 43.8, 205.4 ± 9.7 vs. 308.3 ± 111.7, 193.5 ± 43.8 vs. 81.1 ± 49.7°/s). The relevant biomechanical differences during the serve were identified, highlighting the changes in joint angles and angular velocities between the groups, providing meaningful information for coaches and players to improve their serve proficiency.

Tennis is an asymmetric sport characterized by a systematic repetition of specific movements that may cause disturbances in muscular strength, power, and torque. Thus, we assessed (i) the torque, power, ratio production, and bilateral asymmetries in the shoulder’s external and internal rotations at 90 and 180°/s angular velocities, and (ii) the point duration influence of the above-mentioned variables. Twenty competitive tennis players performed external and internal shoulder rotations; an isokinetic evaluation was conducted of the dominant and non-dominant upper limbs before and after five and ten forehands. A higher torque production in the shoulder’s internal rotations at 90 and 180°/s was observed for the dominant vs. non-dominant sides (e.g., 63.1 ± 15.6 vs. 45.9 ± 9.8% and 62.5 ± 17.3 vs. 44.0 ± 12.6% of peak torque/body mass, p < 0.05). The peak torque decreased only after ten forehands (38.3 ± 15.8 vs. 38.2 ± 15.8 and 39.3 ± 16.1 vs. 38.1 ± 15.6 Nm, respectively, p < 0.05), but without impacting speed or accuracy. Unilateral systematic actions of tennis players caused contralateral asymmetries, evidencing the importance of implementing compensatory training. The forehand kinematic assessment suggests that racket and wrist amplitude, as well as speed, are important success determinants in tennis.

Background/Objectives: Although cultural heritage conservators and restorers face consistent exposure to a multifaceted range of occupational hazards, research on their health remains limited. This systematic review aims to explore and synthesize the prevalence and types of occupational diseases among conservators and restorers of cultural heritage. It also intends to map populations, interventions, contexts and other relevant information to assess the current state of knowledge and identify gaps in the literature on the occupational health of conservation and restoration professionals. Methods: The systematic review followed PRISMA 2020 guidelines and the Cochrane handbook. Eligible studies were identified through comprehensive searches of databases, and inclusion criteria were applied to select relevant articles. The protocol was designed according to PRISMA 2020, Prisma-ScR guidelines and the Cochrane handbook. The searches were conducted on 23 May 2024 in PubMed, Scopus and Web of Science (core collection). The risk-of-bias assessment was performed using the Cochrane method for non-randomized studies (RoBANS). Results: Respiratory symptoms were the most prevalent occupational health issue, affecting 28% of cases. General symptoms and abdominal issues each accounted for 20% and 18%, respectively, while musculoskeletal disorders were reported in 14% of cases, primarily affecting the neck, back, shoulders and wrists due to prolonged static postures and repetitive movements. Dermatological and irritation manifestations were reported in 10% of cases. Additionally, 10% of cases involved specific diseases such as pneumonia and cancer. The risk-of-bias assessment revealed significant methodological heterogeneity, with notable gaps in exposure assessment and disease outcome reporting across studies. Conclusions: This analysis highlights the different health risks faced by conservators and restorers of cultural heritage, underscoring the need for standardized methodologies and prospective studies to increase the data on occupational risks.

The aim of this paper is to understand how various factors such as maturation, peak height velocity, body growth and the effect of relative age can interfere with the athlete's development in sports and in personal terms. Studies indicate that athletes’ development is made up of several stages of maturation, and it is likely that they may occur at different timings depending on the athlete, their birth date, their upbringing, and the type of practice they have undertaken. Thus, we will have to be aware of the prediction we make of an athlete’s progression because this maturational timing influences both the physical and mental progression of the athlete. This is especially true given that evidence shows that those born in the first semester of the season or year may have early advantages over those born in the second semester. This may include finding ways to limit the ability to give more means and selection to teams or players that are stronger or more mature.

Due to the constant high physical strain on tennis players during a match, the effect of a prolonged serve game on torque, power and work of the shoulder external and internal rotations, as well as on serve speed and precision, was investigated. Eighteen male competitive tennis players performed shoulder external and internal rotations (90º of abduction) at 180 and 300º/s on an isokinetic dynamometer before and after 12 points with one flat serve plus forehands and simulated backhands. When comparing pre and post moments, torque and power decreased in external (0.41 ± 0.07 vs 0.39 ± 0.06 N.m/kg and 71.1 ± 27.3 vs 59.7 ± 27.1 W) and internal (0.54 ± 0.10 vs 0.50 ± 0.13 N.m/kg and 91.7 ± 30.7 vs 80.1 ± 38.1 W) rotations at 300º/s, with p ≤ 0.05. Serve speed decreased after the fifth and sixth point (142.0 ± 20.1 vs 132.5 ± 15.3 km/h) and between clusters 1-6 and 7-12 (141.7 ± 15.5 vs 134.9 ± 12.4 km/h), with p ≤ 0.01. Serve precision decreased at the fifth and eighth points, with the highest score recorded at the end of the game. Training should focus on improving players ability to maintain performance during consecutive points, enhancing technical proficiency.