Heart rates were monitored and time – motion analysis performed for 10 players (mean age 25.6 years, s = 2.5; body mass 73.8 kg, s = 5.7 kg; height 1.75 m, s = 0.06) during four competitive futsal matches. Mean heart rate during the match was 90% (s = 2) of maximum heart rate. Heart rate records were classified based on the percentage of time spent in three zones (>85%, 85 – 65%, and <65% maximum heart rate); players spent 83%, 16%, and 0.3% in these three zones, respectively. During the second period, there was a significant reduction (P < 0.01) in the percentage of time spent at an intensity above 85% of maximum heart rate (first vs. second period: 86% vs. 79%). Players' movements were classified as standing, walking, jogging, medium-intensity running, high-intensity running, and sprinting (maximal speed running). Time – motion analysis indicated that the mean distance covered per minute of play was 117.3 m (s = 11.6), of which 28.5% (s = 2.2) was covered while performing medium-intensity running, 13.7% (s = 2) during high-intensity running, and 8.9% (s = 3.4) while sprinting. From the results, we conclude that futsal is a multiple-sprints sport in which there are more high-intensity phases than in soccer and other intermittent sports.

Anterior cruciate ligament (ACL) is one of the most concerning injuries for football players. The aim of this review is to investigate the effects of exercise-based interventions targeting at reducing ACL injury rate or mitigating risk factors of ACL injury in adult football players. Following PRISMA guidelines, a systematic search was conducted in CINAHL, Cochrane Library, PubMed, Scopus, SPORTDiscus and Web of Science. Studies assessing the effect of exercise-based interventions in ACL injury incidence or modifiable risk factors in adult football players were included. 29 studies evaluating 4502 male and 1589 female players were included (15 RCT, 8 NRCT, 6 single-arm): 14 included warm-up, 7 resistance training, 4 mixed training, 3 balance, 1 core stability and 1 technique modification interventions. 6 out of 29 studies investigated the effect of interventions on ACL injury incidence, while the remaining 23 investigated their effect on risk factors. Only 21% and 13% studies evaluating risk of injury variables reported reliability measures and/or smallest worthwhile change data. Warm-up, core stability, balance and technique modification appear effective and feasible interventions to be included in football teams. However, the use of more ecologically valid tests and individually tailored interventions targeting specific ACL injury mechanisms are required.

The aim of this study was to determine the influence of barefoot running on foot-strike patterns, eversion-inversion, running speed and vertical foot rotation in endurance runners. Eighty healthy recreational runners (age = 34.11 ± 12.95 years old, body mass index = 22.56 ± 2.65 kg · m(-2)) performed trials in shod/unshod running conditions on a treadmill at comfortable and competitive self-selected speeds. Data were collected by systematic observation of lateral and back recordings at 240 Hz. McNemar's test indicated significant differences between shod/unshod conditions and foot strike at comfortable and competitive speeds (P < 0.001). Speed was related to vertical foot rotation type for shod (P < 0.01) and unshod conditions (P < 0.05). Significant differences were found between shod/unshod conditions in foot rotation at comfortable running speeds (P < 0.001) and competitive running speeds (P < 0.01). No significant difference was found in inversion or eversion (P ≥ 0.05). In conclusion, the results suggest that running kinematics, in terms of foot-strike patterns and vertical foot rotation, differ between shod/unshod conditions, while the inversion or eversion degree remains unchanged.

This systematic review aims to synthesise the effects of current shoe models in each shoe category and their specific features on running economy, performance and biomechanics. Electronic databases such as Web of Science, SPORTDiscuss, PubMed and Scopus were used to identify studies from 2015 to date. Due to the existing lack of consensus to define running shoes, only studies that specified the shoe brand and models used to assess their effect over runners with a certain level of fitness and training routine were included. Quality assessment of cross-sectional and intervention studies was conducted by three independent raters using a modified version of the Quality Index and the PEDro scale, respectively. A total of 36 articles were finally included, involving the analysis of 61 different shoe models over 10 different topics (i.e., running economy, running performance, spatiotemporal parameters, ground reaction forces, joint stiffness, achilles tendon, plantar pressure, tibiofemoral load, foot strike pattern and joint coordination). With this review, runners and practitioners in the field that are concerned about selecting a suitable shoe for performance, training, or injury prevention functionality have clear information about the effects of the current shoe models and their specific features.

Accuracy and speed are related to performance in tennis. Most research has focused on speed and little is known about the probabilistic structure of error (i.e. accuracy). In the present study 31 advanced players performed a standardised test and accuracy was measured using video analysis. Parameters describing 95% confidence ellipses (CEs) of forehand and backhand were calculated to determine the probabilistic structure of errors. Results showed that for both groundstrokes the long axis of the CEs was oriented almost parallel to the sideline. Despite greater ball speed (~107.2 vs. ~97.3 m • s⁻¹; p < 0.001), the forehand showed a smaller longitudinal distance to the target than the backhand (~123.3 vs. ~164.0 cm; p = 0.024) and a smaller CE area (~34.4 vs. ~40.3 m²; p = 0.045). This means that tennis shot placements fit a bivariate normal distribution (represented by an ellipse), similar to other throwing sports, with differences between the forehand and backhand. Further research will need to explore the underlying causes of these distributions, which in turn may open up opportunities for coaches to modify them in their players according to what is deemed most vital for improved performance.