Background: Volleyball is among the five most popular sports in the world. Regardless of level and age, volleyball athletes perform fast high-impact movements such as jumps, landings, and changes in direction, demanding motor and sensory skills to avoid injuries. The available scientific literature provides information regarding the incidence of injuries in volleyball, but the evidence of injuries in young volleyball athletes (12–18 years old) is not well defined. Therefore, a systematic review was conducted to investigate the incidence and prevalence of injuries in young volleyball players. Methods: This systematic review was conducted according to the PRISMA recommendations and prospectively registered in PROSPERO (ID: CRD42022344623). An electronic search was conducted in the following databases: Web of Science, PubMed, and SportDiscuss via EBSCO in August 2022 and March 2023. Inclusion criteria followed the PICOS acronym: (P) youth volleyball players; (I) volleyball; (C) none; (O) incidence and/or prevalence of injury; and (S) cohort studies. The risk of bias was analysed using the adapted STROBE instrument. Results: Five studies were included in the qualitative analysis. They had a mean methodological quality of 6 (range 4–8) on the modified STROBE scale. Injury incidence was presented in varying ways, ranging from 1.51 injuries/1000 player hours to 12.4 injuries/10,000 athlete exposures (AEs). The prevalence was 1.6 ± 1.7 per 100 AEs. A total sample of 3698 youth volleyball athletes predominantly females was found. The body sites with the highest rate of injuries were the ankle, the distal portion of the upper limbs (wrist/hand/fingers) and the knee, respectively. Conclusion: There was remarkable variability in the rate of injuries and the form of presentation between the studies. In addition, junior volleyball athletes had lower injury rates compared to other sports practised in high school, and older athletes had higher injury rates.

Background: Ankle sprain is the most common lower limb injury in physically active individuals. Loss of function, decreased postural control (PC), strength deficit, and reduced range of motion (ROM) are common after acute lateral ankle sprains. Some patients experienced long lasting symptoms, with recurrent sprains, and episodes of giving-way: a condition known as chronic ankle instability (CAI). Evaluating the function in patients with CAI in the clinical environment is important to identify the severity of the condition, in addition to allowing to assess the effectiveness of a given treatment. The aim of this study was to investigate the validation of the Foot and Ankle Ability Measure (FAAM) and the Foot and Ankle Outcome Score (FAOS) in terms of muscle strength, PC and ROM in adults with CAI.Methods: This is a cross-sectional study. Individuals with CAI aged between 18 and 45 years were eligible. Individuals with CAI were identified using the Identification of Functional Ankle Instability (IdFAI). All patients filled in the FAAM and FAOS scores. Muscle strength was assessed by manual dynamometry, ROM by the Lunge test, PC by computerized posturography, modified Star Excursion Balance Test (mSEBT) and modified Balance Error Score System (mBESS).Results: 50 participants were enrolled in the present study. The mean age of the patients was 27.2 ± 6.3 years, and the mean body mass index was 26.4 ± 4.8 kg/m². 58% (29 of 50) were men and 42% (21 of 50) women. 18 individuals had unilateral (36%) and 32 bilateral (64%) CAI. The results of FAAM were associated with MCT, mSEBT, invertor muscles strength, plantar flexor muscles strength, dorsiflexor muscles strength, and external hip rotator muscles strength (P < 0.05). The results of FAOS were associated with mSEBT, invertor muscles strength, plantar flexor muscles strength, dorsiflexor muscles strength, evertor muscles strength, and external hip rotator muscles strength, and mBEES (P < 0.05).Conclusion: Both the FAAM and FAOS demonstrated validity to evaluate postural control and muscle strength in patients with CAI, while no association was found in relation to ankle dorsiflexion.

Background: The combination of resistance training (RT) and aerobic training is believed to achieve the best effects. Several different aerobic training methods have emerged in combination with or as a substitute for traditional RT. This study wished to verify which RT is safest in terms of injury prevalence and incidence. Also, it ascertained the characteristics of the injured subjects, the level of severity of the injuries and what definitions of injuries the available studies use.Methods: This systematic review followed the PRISMA recommendations and was registered in PROSPERO with the number CRD42021257010. The searches were performed in the PubMed, Cochrane and Web of Science, electronic databases using the Medical Subject Headings terms "Resistance training" or "Strength training" or "Crossfit" or “Weightlifting” or “Powerlifting” combined (AND) with "Injury" or "Injuries" or "Sprain" AND “Incidence” or “Prevalence” AND “Epidemiology” or “Epidemiological” in the title or The last search was performed on March 2023. To be included in the review, the studies had to be available as full text, be clinical trials focusing on epidemiological injuries of resistance training. There was no time limit for the selection of articles. To assess the quality of the studies, the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) was used.Results: The initial literature search resulted in 4982 studies. After reading the titles, abstracts and full text, 28 articles were selected for data extraction. Seventeen investigated the injuries in HIFT/CrossFit, three in powerlifting, three in strength training, three in weightlifting and one in strongman. In addition, one study examined the HIFT/CrossFit and weightlifting. The incidence of injuries presented in the studies ranged from 0.21/1000 h to 18.9/1000 h and the prevalence of injuries was 10% to 82%. In the quality assessment for STROBE, five studies were classified at level A, 21 at level B and two at level C.Conclusion: This systematic review showed that traditional strength training is the safest RT method, and strongman is the least safe regarding injuries. Few studies have been rated highly according to STROBE. Furthermore, few studies have been published on some RT methods. These two factors make it difficult to generalize the results.

Background: The shoulder joint is the most commonly injured joint in CrossFit practitioners, because of the high intensity and loads associated with this sport. Despite the large number of clinical cases, there is a shortage of studies that investigate influence of biomechanical aspects of upper limbs' injuries on CrossFit practitioners. This study hypothesized that there would be a difference in function, strength, and muscle activation between Crossfit practitioners with and without shoulder pain. Methods: We divided 79 Crossfit practitioners into two groups according to whether they reported pain (n = 29) or no pain (n = 50) in the shoulder during Crossfit training. Muscle function, strength, and activation were assessed using the Disability Arm, Shoulder and Hand function questionnaire, Upper Quarter Y Balance Test and Closed Kinetic Chain Upper Extremity Stability Test shoulder tests, isometric muscle strength assessment by manual dynamometry and muscle activation by surface electromyography and pain report. Results: The function based on questionnaire was associated with pain (p = 0.004). We observed a statistically significant difference between the two groups only in the surface electromyography activity of the lower trapezius, and in the variables of shoulder pain and function (p = 0.038). Conclusion: Crossfit practitioners with shoulder pain occurring during training showed good function and stability of the shoulder joint, but there was a reduction in the activation of stabilizing muscles, especially the lower trapezius. Trial registration Registro Brasileiro de Ensaios Clinico (Brasilian National Registry) with the ID: RBR-2gycyv.