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Sports performance initiation is of significant interest in sports sciences, particularly in beach volleyball (BV), where players usually combine indoor and BV disciplines in the formative stages. This research aimed to apply an electronic performance tracking system to quantify the physical-conditional performance of young male BV players during competition, considering age group (U15 or U19), sport specialisation (indoor or beach) and the set outcome (winner or loser). Thirty-two young male players, categorised by age and sport specialisation, were analysed during 40 matches using electronic performance tracking systems (Wimu PROTM). Data collected were the set duration, total and relative distances covered, and number and maximum values in acceleration and deceleration actions. U19 players and BV specialists, compared to their younger and indoor counterparts, covered more distance (719.25 m/set vs. 597.85 m/set; 719.25 m/set vs. 613.15 m/set) and exhibited higher intensity in terms of maximum values in acceleration (4.09 m/s2 vs. 3.45 m/s2; 3.99 m/s2 vs. 3.65 m/s2) and deceleration (−5.05 m/s2 vs. −4.41 m/s2). More accelerations (557.50 n/set vs. 584.50 n/set) and decelerations (561.50 n/set vs. 589.00 n/set) were found in indoor players. Additionally, no significant differences were found in variables regarding the set outcome. These findings suggest that both age and specialisation play crucial roles in determining a great physical-conditional performance in young players, displaying a higher volume and intensity in external load metrics, whereas indoor players seem to need more accelerations and decelerations in a BV adaptation context. These insights highlight the age development and sport specialisation in young volleyball and BV athletes. [ABSTRACT FROM AUTHOR]

The gastrocnemius muscle plays a crucial role in transmitting and generating energy during standing explosive accelerations, and as a consequence, is a muscle with high injury prevalence, especially the medial gastrocnemius (MG). This study aimed to compare the neuromuscular activation of the lateral gastrocnemius (LG) and MG during one of the most common standing explosive accelerations performed in team sports—the false start that occurs in jumps where the leg steps back before moving forward. Forty-two physically active participants (34 males: age = 24 ± 5 years, body mass = 73 ± 10.4 kg; and 8 females: age = 26 ± 5 years, body mass = 57.1 ± 6.8 kg) underwent electromyography analysis of the MG and LG in the four first foot contacts of standing explosive acceleration. The results showed that the third contact differed significantly from others (LG vs. MG: 76.48 ± 3.10 vs. 66.91 ± 2.25, p = 0.01, ES = 0.5), with the LG exhibiting earlier activation and higher peak sEMG activity compared to the MG (LG vs. MG: 0.12 ± 0.01 vs. 0.13 ± 0.01, p = 0.02, ES = 0.4). Additionally, the MG displayed longer duration contractions in all the foot contacts except the third foot contact. In conclusion, the MG showed an earlier activation timing and a longer duration of contraction than the LG in the first foot contact. Additionally, the third foot contact showed a different pattern of neuromuscular activation between the MG and LG compared to the rest of the foot contacts. [ABSTRACT FROM AUTHOR]

The First-Person Shooter is a very popular genre in electronic sports (esports), where there are different aiming techniques such as Aim Flicking and Aim Tracking. Although the mouse grip is suggested as one of the most important factors in gaming performance, there is a lack of evidence on this topic. Therefore, the purpose of the present study was to determine the performances of three types of mouse grips (palm grip, claw grip, and fingertip grip) in two different tasks (flicking and tracking tasks) by analyzing kinematic and scoring variables. Twenty-two participants performed the tasks on a computer with the same monitor and mouse, each using their preferred grip: palm grip, claw grip, and fingertip grip. The aim400kg was used to perform the tasks, and a camera system (Optitrack's Flex 3) was used to capture the mouse movement. The results from the flicking task indicated significant differences in the minimum cursor trajectory, with higher values observed in the claw grip compared to both the palm and fingertip grips. However, no significant differences were observed in the tracking task in terms of velocity, acceleration, or hand movement. Moreover, only high correlations were observed in the flicking task between Score and Reaction Time (r = −0.911) and between Score and Total Distance (r = 0.724). In conclusion, the mouse grip does not affect the Aim Flicking or Aim Tracking task performance. This study has revealed interesting results related to performance, including correlations between the Score, Reaction Time, and Total Distance in flicking tasks. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate skin temperature (Tsk) asymmetries, using infrared thermography, in professional padel players before (PRE), after (POST) and 10 min after training (POST10), and their relationship with perceptual variables and training characteristics. Thermal images were taken of 10 players before, after and 10 min after a standardized technical training. After training, Tsk of the dominant side was higher than before training in the anterior forearm (30.8 ± 0.4 °C vs. 29.1 ± 1.2 °C, p < 0.01; ES = 1.9), anterior shoulder (31.6 ± 0.6 °C vs. 30.9 ± 0.6 °C, p < 0.05; ES = 1.0) posterior arm (29.5 ± 1.0 °C vs. 28.3 ± 1.2 °C, p < 0.05; ES = 1.0), and posterior forearm (30.8 ± 0.9 °C vs. 29.3 ± 1.6 °C, p < 0.05; ES = 1.1). Likewise, these differences were significant POST10 in the anterior arm, anterior forearm, anterior shoulder, posterior arm and posterior forearm. Comparing the different moments of measurement (PRE, POST and POST10), the temperature was higher POST10 in all the regions analyzed except for the shoulder, abdominals, and lower back. Also, correlations were found between fatigue variation and temperature variation between limbs (Tsk dominance), and no correlation was found except between age and posterior thigh (|r| = 0.69; p < 0.05), and between the racket mass and anterior knee (|r| = 0.81; p < 0.01). In conclusion, infrared thermography allows monitoring of skin asymmetries between limbs in professional padel players, but these asymmetries were not related to overall fatigue variation, overall pain variation, years of experience and training hours. [ABSTRACT FROM AUTHOR]

The use of custom-made foot orthoses has been associated with numerous benefits, such as decreased impact accelerations. However, it is not known whether this effect could be due to better customisation. The present study analysed the effects of the first generation of a microwavable prefabricated self-customised foot orthosis vs. a prefabricated standard one on impact accelerations throughout a prolonged run. Thirty runners performed two tests of 30-min running on a treadmill, each one with an orthosis condition. Impact acceleration variables of tibia and head were recorded every 5 min. Microwavable self-customised foot orthosis increased the following variables in the first instants compared to the prefabricated standard one: tibial peak (min1: 6.5 (1.8) vs. 6.0 (1.7) g, P =.009, min5: 6.6 (1.7) vs. 6.2 (1.7) g, P =.035), tibial magnitude (min1: 8.3 (2.6) vs. 7.7 (2.4) g, P =.030, min5: 8.5 (2.6) vs. 7.9 (2.5) g, P =.026) and shock attenuation (min1: 61.4 (16.8) vs. 56.3 (16.3)%, P =.014, min5: 62.0 (15.5) vs. 57.2 (15.3)%, P =.040), and tibial rate throughout the entire run (504.3 (229.7) vs. 422.7 (212.9) g/s, P =.006). However, it was more stable throughout 30-min running (P <.05). These results show that the shape customisation entailed by the thermoformable material does not provide impact acceleration improvements. [ABSTRACT FROM AUTHOR]

Small skin temperature asymmetries are claimed to indicate injuries, but the influence of measurement conditions and technical aspects of image acquisition are concerns for determining temperature asymmetries. This research determines whether distance and camera specifications affect thermal asymmetries detection. We simulated thermal asymmetries filling two glasses with water at different temperatures measured at two distances (0.7 and 1.5 m) using four different infrared cameras (T1020, E60BX, C2 and FLIR ONE). Linear regression verified the similarity between each camera and the T1020 camera (gold standard). The intraclass correlation coefficient assessed the inter-camera reproducibility. Linear regression reported increasing adjustment using mean temperature, with lower values at 1.5 m between the T1020 and FLIR ONE (0.7 m, r = 0.58; 1.5 m, r = 0.34), C2 (0.7 m, r = 0.90; 1.5 m, r = 0.62) and E60BX (0.7 m, r = 0.96; 1.5 m, r = 0.68). Higher inter-camera reproducibility was observed at 0.7 m than 1.5 m. It is preferable to take thermal images with shorter distances and to prioritise cameras with superior hardware characteristics. The portability of FLIR ONE and C2 may be an advantage in studies investigating expected differences greater than 0.05ºC and larger regions of interest. [ABSTRACT FROM AUTHOR]

Technological development has boosted the use of multi-sensor devices to monitor athletes' performance, but the location and connectivity between devices have been shown to affect data reliability. This preliminary study aimed to determine whether the placement of a multi-sensor device (WIMU PROTM) could affect the heart rate signal reception (GARMINTM chest strap) and, therefore, data accuracy. Thirty-two physical education students (20 men and 12 women) performed 20 min of exercise in a cycle ergometer based on the warm-up of the Function Threshold Power 20 test in laboratory conditions, carrying two WIMU PROTM devices (Back: inter-scapula; Bicycle: bicycle's handlebar—20 cm from the chest) and two GARMINTM chest straps. A one-dimensional statistical parametric mapping test found full agreement between the two situations (inter-scapula vs. bicycle's handlebar). Excellent intra-class correlation values were obtained during the warm-up (ICC = 0.99, [1.00–1.00], p < 0.001), the time trial test (ICC = 0.99, [1.00–1.00], p < 0.001) and the cool-down (ICC = 0.99, [1.00–1.00], p < 0.001). The Bland–Altman plots confirmed the total agreement with a bias value of 0.00 ± 0.1 bpm. The interscapular back placement of the WIMU PROTM device does not affect heart rate measurement accuracy with a GARMINTM chest strap during cycling exercise in laboratory conditions. [ABSTRACT FROM AUTHOR]

Context: Although skin-temperature assessment has received much attention in recent years as a possible internal-load measurement, scientific evidence is scarce. Purpose: To analyze baseline skin temperature and its rewarming through means of a cold-stress test before and after performing a marathon and to study the association between skin temperature and internal/external-load measurements. Methods: A total of 16 runners were measured 48 and 24 h before and 24 and 48 h after completing a marathon. The measurements on each day of testing included urine biomarkers of oxidative stress, pain and fatigue perception, skin temperature (at baseline and after a cold-stress test), and jump performance. Results: Reduced jump performance (P <.01 and effect size [ES] = 0.5) and higher fatigue and pain perception were observed 24 h after the marathon (P <.01 and ES > 0.8). Although no differences in baseline skin temperature were observed between the 4 measuring days, posterior legs presented lower constant (P <.01 and ES = 1.4) and higher slope (P =.04 and ES = 1.1) parameters in the algorithmic equations fitted for skin-temperature recovery after the cold-stress test 24 h after the marathon than on the day before the marathon. Regressions showed that skin-temperature parameters could be predicted by the ratio of ortho-tyrosine isomer to phenylalanine (oxidative stress biomarker) and body fat composition, among others. Conclusions: Although baseline skin temperature was not altered 24 or 48 h after a marathon, the application of cold stress after the marathon would appear to be a good method for providing information on vasoconstriction and a runner's state of stress. [ABSTRACT FROM AUTHOR]