The Acute: Chronic Workload Ratio and Injury Risk in Semiprofessional Football Players.

The purpose of this study was to analyze the association and predictive capacity between the acute:chronic workload ratio (ACWR) and non-contact injuries in a semiprofessional football team. Seventeen football or soccer players from a Spanish Third Division football team participated voluntarily in this study. A prospective longitudinal study was developed during the 2020/2021 season. Twenty-four weeks were analyzed from October to March, including a regenerative microcycle due to the absence of competition during Christmas. Rate of perceived exertion (RPE) and session-rate of perceived exertion (sRPE) were registered for every training and game session. Afterward, acute and chronic workloads were calculated, and ACWR was subsequently derived from them. Furthermore, non-contact injuries were registered during the period mentioned. The main findings were that there is a poor correlation between the ACWR and non-contact injuries (r=0.069 (p<0.05)), and the use of the ACWR by itself is insufficient to predict the occurrence of non-contact injuries in a semiprofessional football team. Consequently, the ACWR is not an useful predictive tool for injuries in semiprofessional football teams.

The relationship of muscle oxygen saturation analyzer with other monitoring and quantification tools in a maximal incremental treadmill test.

Introduction: The study aims to explore whether NIRS derived data can be used to identify the second ventilatory threshold (VT2) during a maximal incremental treadmill test in non-professional runners and to determine if there is a correlation between SmO2 and other valid and reliable exercise performance assessment measures or parameters for maximal incremental test, such as lactate concentration (LT), RPE, HR, and running power (W). Methods: 24 participants were recruited for the study (5 women and 19 men). The devices used consisted of the following: i) a muscle oxygen saturation analyzer placed on the vastus lateralis of the right leg, ii) the Stryd power meter for running, iii) the Polar H7 heart rate band; and iv) the lactate analyzer. In addition, a subjective perceived exertion scale (RPE 1-10) was used. All of the previously mentioned devices were used in a maximal incremental treadmill test, which began at a speed of 8 km/h with a 1% slope and a speed increase of 1.2 km/h every 3 min. This was followed by a 30-s break to collect the lactate data between each 3-min stage. Spearman correlation was carried out and the level of significance was set at p < 0.05. Results: The VT2 was observed at 87,41 ± 6,47% of the maximal aerobic speed (MAS) of each participant. No relationship between lactate data and SmO2 values (p = 0.076; r = -0.156) at the VT2 were found. No significant correlations were found between the SmO2 variables and the other variables (p > 0.05), but a high level of significance and strong correlations were found between all the following variables: power data (W), heart rate (HR), lactate concentration (LT) and RPE (p < 0.05; r > 0.5). Discussion: SmO2 data alone were not enough to determine the VT2, and there were no significant correlations between SmO2 and the other studied variables during the maximal incremental treadmill test. Only 8 subjects had a breakpoint at the VT2 determined by lactate data. Conclusion: The NIRS tool, Humon Hex, does not seem to be useful in determining VT2 and it does not correlate with the other variables in a maximal incremental treadmill test.

Detection of Upper Limb Asymmetries in Athletes According to the Stage of the Season-A Longitudinal Study.

Sports injuries can affect the performance of athletes. For this reason, functional tests are used for injury assessment and prevention, analyzing physical or physiological imbalances and detecting asymmetries. The main aim of this study was to detect the asymmetries in the upper limbs (right and left arms) in athletes, using the OctoBalance Test (OB), depending on the stage of the season. Two hundred and fifty-two participants (age: 23.33 ± 8.96 years old; height: 178.63 ± 11.12 cm; body mass: 80.28 ± 17.61 kg; body mass index: 24.88 ± 4.58; sports experience: 12.52 ± 6.28 years), practicing different sports (rugby, athletics, football, swimming, handball, triathlon, basketball, hockey, badminton and volleyball), assessed with the OB in medial, superolateral, and inferolateral directions in both arms, in four moments of the season (May 2017, September 2017, February 2018 and May 2018). ANOVA test was used with repeated measures with a p ≤ 0.05, for the analysis of the different studied variances. Significant differences were found (p = 0.021) in the medial direction of the left arm, between the first (May 2017) and fourth stages (May 2018), with values of 71.02 ± 7.15 cm and 65.03 ± 7.66 cm. From the detection of asymmetries, using the OB to measure, in the medial, superolateral and inferolateral directions, mobility and balance can be assessed. In addition, it is possible to observe functional imbalances, as a risk factor for injury, in each of the stages into which the season is divided, which will help in the prevention of injuries and in the individualization of training.

Why Percussive Massage Therapy Does Not Improve Recovery after a Water Rescue? A Preliminary Study with Lifeguards.

The aim of this study was to analyze the effects of percussive massage therapy (PMT) on lifeguards' recovery after a water rescue, in comparison with passive recovery. Methods: A quasi-experimental crossover design was conducted to compare passive recovery (PR) and a PMT protocol. A total of 14 volunteer lifeguards performed a simulated 100 m water rescue and perceived fatigue and blood lactate were measured as recovery variables after the rescue and after the 8-min recovery process. Results: There were no differences between PMT and PR in lactate clearance (p > 0.05), finding in both modalities a small but not significant decrease in blood lactate. In perceived fatigue, both methods decreased this variable significantly (p < 0.001), with no significant differences between them (p > 0.05). Conclusions: PMT does not enhance recovery after a water rescue, in comparison with staying passive. Despite PMT appearing to be adequate for recovery in other efforts, it is not recommended for lifeguards' recovery after a water rescue.

A Comparison between Three Different Techniques Considering Quality Skills, Fatigue and Hand Pain during a Prolonged Infant Resuscitation: A Cross-Over Study with Lifeguards.

The aim of the study was to compare the quality of CPR (Q-CPR), as well as the perceived fatigue and hand pain in a prolonged infant cardiopulmonary resuscitation (CPR) performed by lifeguards using three different techniques. A randomized crossover simulation study was used to compare three infant CPR techniques: the two-finger technique (TF); the two-thumb encircling technique (TTE) and the two-thumb-fist technique (TTF). 58 professional lifeguards performed three tests in pairs during a 20-min period of CPR. The rescuers performed compressions and ventilations in 15:2 cycles and changed their roles every 2 min. The variables of analysis were CPR quality components, rate of perceived exertion (RPE) and hand pain with numeric rating scale (NRS). All three techniques showed high Q-CPR results (TF: 86 ± 9%/TTE: 88 ± 9%/TTF: 86 ± 16%), and the TTE showed higher values than the TF (p = 0.03). In the RPE analysis, fatigue was not excessive with any of the three techniques (values 20 min between 3.2 for TF, 2.4 in TTE and 2.5 in TTF on a 10-point scale). TF reached a higher value in RPE than TTF in all the intervals analyzed (p < 0.05). In relation to NRS, TF showed significantly higher values than TTE and TTF (NRS minute 20 = TF 4.7 vs. TTE 2.5 & TTF 2.2; p < 0.001). In conclusion, all techniques have been shown to be effective in high-quality infant CPR in a prolonged resuscitation carried out by lifeguards. However, the two-finger technique is less efficient in relation to fatigue and hand pain compared with two-thumb technique (TF vs. TTF, p = 0.01).

Instruments to Assess Physical Activity in Primary Education Students with Autism Spectrum Disorder: A Systematic Review.

The scientific evidence supports that physical inactivity in childhood is a reality throughout the world which generates important consequences in the global development of children. Young people with Autism Spectrum Disorder (ASD), due to the characteristics of the disorder they suffer, constitute a group at risk. Therefore, assessing the levels of physical activity (PA) in this group is fundamental for subsequent decision making and implementation of PA promotion programmes. Consequently, the aim of this systematic review was to identify, summarise and analyse the main instruments used to assess the levels of PA (in terms of time and/or intensity) in primary school children diagnosed with ASD. Scientific articles in English and Spanish published in five databases were reviewed: PsycINFO, WOS, SPORTDiscus, Scopus and PubMed, following the guidelines of the PRISMA statement. Out of the 605 articles identified, 12 met the previously established inclusion criteria. The instruments used by the studies analysed were divided into two main groups: accelerometers and questionnaires. Both showed different strengths and limitations but agreed on the low levels registered of PA in children with ASD. For this reason, it is considered necessary that further research be carried out in this field, as well as the development and implementation of sports programmes adjusted and adapted to the needs and characteristics of the ASD group.