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Background: Current research relates jaw clenching to athletic performance, in terms of force and agility. However, the impact of jaw clenching on sports accuracy is unclear. Objectives: To analyse the impact of jaw position and chewing type on free‐throw accuracy and electromyographic (EMG) activity of masticatory muscles during free‐throws. Methods: Cross‐sectional study with 25 female basketball players aged 18–44. Each participant executed 18 free‐throws under three different jaw conditions: mandibular rest, maximum intercuspation, and with interdental cotton rolls, in randomised order. Results: Chewing type and jaw position were not associated with shooting accuracy (p = 0.106; p = 0.778). There was a positive correlation between EMG activity of the right masseter and free‐throw accuracy at maximum intercuspation (rs = 0.402; p = 0.046). In contrast, negative correlations were found with other muscles when the occlusal vertical dimension was altered (rs = −0.619, p = 0.001; rs = −0.490; p = 0.013; rs = −0.534; p = 0.006). The chewing type affected the EMG of the left masseter in the altered occlusal vertical dimension (H = 6.969; p = 0.031). Significant differences in EMG recordings were observed across different mandibular positions during free‐throws (p < 0.001). Conclusions: While jaw positioning and chewing type do not impact free‐throw accuracy in amateur female basketball players, the EMG activity of masticatory muscles is linked to shooting performance. This highlights the need for further research on motor behaviour of masticatory muscles in precision sports, especially for athletes using intraoral devices. [ABSTRACT FROM AUTHOR]

(1) Background: Leg length discrepancy (LLD), regardless of its origin, is a very common pathology that can contribute to low back pain. Various authors have pointed out its relationship with the lack of activation of both the gluteus medius (GM) and the ipsilateral erector spinae (ES). The purpose of this study was to identify the activation of the ES and GM with different simulated LLDs, correlating this activation with LBP. In turn, we evaluated whether ES and GM activity has an effect on jumping ability using a CMJ test. (2) Method: A sample of healthy subjects was selected to whom an artificial LLD was applied using 0.5, 1, and 1.5 cm insoles. These three heights were measured using EMG while the subjects walked and performed a counter movement jump (CMJ). The measurements of the insole heights were carried out in random order using a Latin square. Muscle activation patterns were recorded for 30 s at each of the insole heights while the patients walked at 5.7 km/h and they were compared with the maximum voluntary contraction (MVC), both on the ipsilateral and contralateral sides. These muscles were then measured under the same circumstances during the performance of the CMJ. (3) Results: We found statistically significant differences in the flight heights in both the CMJ and DJ. In the comparison, significant differences were found in the flight heights of the CMJ and the DJ using the 5 mm insoles, and in the case of the DJ, also without insoles, with respect to the MVC. We found statistically significant differences in the activation of the GM with the differences in insoles, but not in the activation of the Es in relation to the different insole heights. (4) Conclusions: Insoles of different heights caused activation differences in the medius on the side where the insoles were placed. We can relate this difference in activation to LBP. In relation to the ES, no significant differences were found in the activation of the ipsilateral side of the insole. [ABSTRACT FROM AUTHOR]

Deep dry needling (DDN) and percutaneous electrolysis (PE) provide the benefit of the mechanical effect of the needle, and PE adds the potential advantages of the galvanic current it incorporates in myofascial trigger points (MTrPs) therapy. The aim of this study was to compare the short-term efficacy between PE and DDN on active MTrPs of the levator scapulae by considering pain intensity. A simple-blind randomized controlled trial was carried out, recruiting patients suffering from non-specific neck pain lasting more than 3 months and with active MTrPs in the levator scapulae muscle (n = 52). Patients were divided into intervention (PE; n = 26) and control (DDN; n = 26) groups and received one treatment session on the active MTrPs of the levator scapulae. Patients were assessed for pain intensity, pressure pain threshold (PPT), cervical range of motion (CROM), neck disability and post-needling soreness, immediately after treatment, at 72 h and at 14 days. In addition, pain during treatment was recorded after the procedure. There were no significant differences for pain intensity, post-needling soreness and PPT. We found significant differences in CROM, immediately after treatment (p = 0.043), and at 72 h (p = 0.045), in favor of the PE group. Significant differences were found for neck disability (p < 0.047), immediately post-treatment, in favor of the DDN group. Moreover, there were significant differences for pain during the intervention (p < 0.002), in favor of the DDN group (4.54 ± 2.21) versus the PE group (6.54 ± 2.27). PE and DDN appear to have similar short-term effects. PE proved to be a more painful treatment than DDN. Clinical trial registry: NCT04157426. [ABSTRACT FROM AUTHOR]

Several studies have shown that gastrocnemius is frequently injured in triathletes. The causes of these injuries are similar to those that cause the appearance of the myofascial pain syndrome (MPS). The ischemic compression technique (ICT) and deep dry needling (DDN) are considered two of the main MPS treatment methods in latent myofascial trigger points (MTrPs). In this study superficial electromyographic (EMG) activity in lateral and medial gastrocnemius of triathletes with latent MTrPs was measured before and immediately after either DDN or ICT treatment. Taking into account superficial EMG activity of lateral and medial gastrocnemius, the immediate effectiveness in latent MTrPs of both DDN and ICT was compared. A total of 34 triathletes was randomly divided in two groups. The first and second groups (n = 17 in each group) underwent only one session of DDN and ICT, respectively. EMG measurement of gastrocnemius was assessed before and immediately after treatment. Statistically significant differences (p = 0.037) were shown for a reduction of superficial EMG measurements differences (%) of the experimental group (DDN) with respect to the intervention group (ICT) at a speed of 1 m/s immediately after both interventions, although not at speeds of 1.5 m/s or 2.5 m/s. A statistically significant linear regression prediction model was shown for EMG outcome measurement differences at V1 (speed of 1 m/s) which was only predicted for the treatment group (R2 = 0.129; β = 8.054; F = 4.734; p = 0.037) showing a reduction of this difference under DDN treatment. DDN administration requires experience and excellent anatomical knowledge. According to our findings immediately after treatment of latent MTrPs, DDN could be advisable for triathletes who train at a speed lower than 1 m/s, while ICT could be a more advisable technique than DDN for training or competitions at speeds greater than 1.5 m/s. [ABSTRACT FROM AUTHOR]