Reliability of Dynamic Shoulder Strength Test Battery Using Multi-Joint Isokinetic Device.

This study aimed to determine the absolute and relative reliability of concentric and eccentric flexion, extension, horizontal abduction, and adduction movements of the shoulder using a functional electromechanical dynamometer (FEMD). Forty-three active male university students (23.51 ± 4.72 years) were examined for concentric and eccentric strength of shoulder flexion, extension, horizontal abduction, and horizontal adduction with an isokinetic test at 0.80 m·s-1. Relative reliability was determined by intraclass correlation coefficients (ICCs) with 95% confidence intervals. Absolute reliability was quantified by the standard error of measurement (SEM) and coefficient of variation (CV). Reliability was very high to extremely high for all movements on concentric and eccentric strength measurements (ICC: 0.76-0.94, SEM: 0.63-6.57%, CV: 9.40-19.63%). The results of this study provide compelling evidence for the absolute and relative reliability of concentric and eccentric flexion, extension, horizontal abduction, and horizontal adduction shoulder isokinetic strength tests in asymptomatic adults. The mean concentric force was the most reliable strength value for all tests.

Muscle Quality Index is inversely associated with psychosocial variables among Chilean adolescents.

A good muscle quality index (MQI) may have an inverse relationship with psychosocial variables of depression, anxiety, and stress in adolescents. Unfortunately, little scientific evidence has related MQI to psychosocial variables in this population. Therefore, this research aimed to determine the relationship between the MQI and psychosocial variables of depression, anxiety, and stress in Chilean adolescents. In this quantitative correlational design study, sixty adolescents participated voluntarily (mean ± standard deviation [SD]: age 15.11 ± 1.78 years). Anthropometric parameters, prehensile strength, MQI, and psychosocial variables were evaluated. The results showed that adolescents with high levels of MQI presented lower levels of depression (7.50 ± 6.06 vs. 10.97 ± 5.94), anxiety (5.64 ± 4.81 vs. 9.66 ± 5.12), and stress (6.79 ± 5.09 vs. 10 ± 5.58), in addition to reported lower abdominal obesity (WtHR, 0.47 ± 0.07 vs. 0.52 ± 0.07) than those with low levels of MQI. The group with high levels of MQI reported a higher prevalence of nonanxiety (81.3%, p = 0.031) and a lower prevalence of abdominal obesity (55.8%, p = 0.023). Likewise, a significant inverse association was evidenced between MQI and depression (ß; -6.18, 95% CI; -10.11: -2.25, p = 0.003), anxiety (ß; -6.61, 95% CI; -9.83: -3.39, p < 0.001) and stress (ß; -4.90, 95% CI; -8.49: -1.32 p = 0.008). In conclusion, the results suggest that high levels of MQI are associated with a higher prevalence of nonanxiety in adolescents and a significant inverse association between MQI and levels of depression, anxiety, and stress.

Vertical Versus Horizontal Training for Improving the Change of Direction Speed in Adult Basketball Players: A Systematic Review and Meta-analysis.

ABSTRACT: Barrera-Domínguez, FJ, Martínez-García, D, Jerez-Mayorga, D, Chirosa-Ríos, LJ, Almagro, BJ, and Molina-López, J. Vertical versus horizontal training for improving the change of direction speed in adult basketball players: a systematic review and meta-analysis. J Strength Cond Res XX(X): 000-000, 2023-The ability to perform changes of direction (COD) is a complex skill that involves the application of multiple force-orientations, and its execution at maximum speed is crucial in basketball players. The present study aimed to synthesize findings from previous interventions classified according to force-orientation (vertical, horizontal, or mixed) and determine their magnitude of the effect on COD performance in basketball players. A systematic review of the literature was performed in several databases (Web of Science, Scopus, SPORTDiscus, and PubMed) following the PRISMA statement and reviewed the quality of the included papers according to the Cochrane Collaboration Guidelines Assessment. Sixteen articles with a total of 21 reports were included to analyze the role of force-orientations in COD performance. For the meta-analysis, the standardized mean differences with 95% confidence intervals (CIs) were calculated to determine the chronic changes induced by training and performed an effect size (ES) analysis with a random-effects model. The results showed that all force-orientations generated improvements in COD performance (ES = -0.47 [95% CI -0.57, -0.36], Z = 8.74 [p < 0.01]). It was a mixed force-orientation that produced the greatest changes (ES = -0.91 [95% CI -1.27, -0.55], Z = 4.96 [p < 0.01]), followed by vertical training (ES = -0.45 [95% CI -0.70, -0.20], Z = 3.51 [p < 0.01]). Horizontal training was the least studied and showed the smallest change (ES = -0.10 [95% CI -0.14, -0.07], Z = 5,71 [p < 0.01]). This meta-analysis demonstrates that mixed vertical and horizontally oriented training may be the most optimal because it offers a greater variety of multidirectional stimuli that better prepares the athlete to deal with complex COD in real-game situations.

On-court throwing activity of male handball players during the European Championship 2020.

The aim of this study was to investigate the on-court throwing activity in regards to playing positions, throwing zones on the court and throwing velocity category during the male European Championship 2020. A local positioning system with microsensors placed both in the shirts of the players and inside the ball itself was used. In total, 6568 throws were retrieved for analysis from the entire tournament. Results showed that first-line players (wings and line players) used their natural zone more to throw (65% left wing, 60% right wing, and 97% line player), showing higher effectiveness from there (p < 0.05). Second lines players distributed more of their throws (45% left back, 50% right back and 32% center back in their natural zones) giving priority to the throws in 6 m, where they showed higher effectiveness (p < 0.05), or between the lines. Considering all players, shots from nearby and intermediate areas corresponded to 83% of the shots showing higher efficiency (p < 0.05) than shots performed from the areas furthest from the goal (14.9%. from zones 6-7-8). Back players mainly performed the highest velocity throws (Category 4 > ~100 km/h) from these furthest areas. Throwing velocity and effectiveness by throwing zones and positions was not significantly modified over the three rounds of the tournament (p > 0.05), indicating no effect of possible fatigue. A higher team ranking was associated with higher throwing efficiency but only for wing players. The results of this research could help handball coaches to better adjust training programs for the improvement of throwing velocity and its transfer to the competition.

Effect of Traditional, Cluster, and Rest Redistribution Set Configurations on Neuromuscular and Perceptual Responses During Strength-Oriented Resistance Training.

ABSTRACT: Cuevas-Aburto, J, Jukic, I, Chirosa-Ríos, LJ, González-Hernández, JM, Janicijevic, D, Barboza-González, P, Guede-Rojas, F, and García-Ramos, A. Effect of traditional, cluster, and rest redistribution set configurations on neuromuscular and perceptual responses during strength-oriented resistance training. J Strength Cond Res 36(6): 1490-1497, 2022-This study aimed to compare the acute effect of traditional (TR), cluster (CL), and rest redistribution (RR) set configurations on neuromuscular and perceptual measures of fatigue. Thirty-one resistance-trained men randomly performed a Control session and 3 experimental sessions consisting of the squat (SQ) and bench press (BP) exercises performed against the 10 repetition maximum load using TR (3 sets of 6 repetitions; 3 minutes of interset rest), CL (3 sets of 6 repetitions; 30 seconds of intraset rest every 2 repetitions; 3 minutes of interset rest), and RR (9 sets of 2 repetitions; 45 seconds of interset rest) set configurations. A significant effect of "set configuration" (p = 0.002) was observed for barbell velocity. The average velocity of the training session was lower for TR compared with CL (% difference = 5.09% in SQ and 5.68% in BP) and RR (% difference = 5.92% in SQ and 2.71% in BP). The 3 set configurations induced comparable decrements in countermovement jump height (% difference from -6.0% to -8.1%) and throwing velocity (% difference from -0.6% to -1.2%). Ratings of perceived exertion (RPE-10) values collected after the sets were higher for TR (SQ: 6.9 ± 0.7 a.u.; BP: 6.8 ± 0.8 a.u.) compared with CL (SQ: 6.2 ± 0.8 a.u.; BP: 6.4 ± 0.7 a.u.) and RR (SQ: 6.2 ± 0.8 a.u.; BP: 6.6 ± 0.9 a.u.), while the session RPE did not differ between the set configurations (p = 0.595). CL and RR set configurations allow for higher velocities and lower RPE values during resistance training sessions not performed to failure in comparison with a TR set configuration.

Reliability and validity of different methods of estimating the one-repetition maximum during the free-weight prone bench pull exercise.

This study examined the reliability and validity of three methods of estimating the one-repetition maximum (1RM) during the free-weight prone bench pull exercise. Twenty-six men (22 rowers and four weightlifters) performed an incremental loading test until reaching their 1RM, followed by a set of repetitions-to-failure. Eighteen participants were re-tested to conduct the reliability analysis. The 1RM was estimated through the lifts-to-failure equations proposed by Lombardi and O'Connor, general load-velocity (L-V) relationships proposed by Sánchez-Medina and Loturco and the individual L-V relationships modelled using four (multiple-point method) or only two loads (two-point method). The direct method provided the highest reliability (coefficient of variation [CV] = 2.45% and intraclass correlation coefficient [ICC] = 0.97), followed by the Lombardi's equation (CV = 3.44% and ICC = 0.94), and no meaningful differences were observed between the remaining methods (CV range = 4.95-6.89% and ICC range = 0.81-0.91). The lifts-to-failure equations overestimated the 1RM (3.43-4.08%), the general L-V relationship proposed by Sánchez-Medina underestimated the 1RM (-3.77%), and no significant differences were observed for the remaining prediction methods (-0.40-0.86%). The individual L-V relationship could be recommended as the most accurate method for predicting the 1RM during the free-weight prone bench pull exercise.

[Association between physical fitness parameters and health related quality of life in Chilean community-dwelling older adults]. / Asociación predictiva entre parámetros de condición física y dimensiones de calidad de vida relacionada con la salud en adultos mayores chilenos insertos en la comunidad.

BACKGROUND: There is no conclusive evidence about the association between physical fitness (PF) and health related quality of life (HRQOL) in older adults. AIM: To seek for an association between PF and HRQOL in non-disabled community-dwelling Chilean older adults. MATERIAL AND METHODS: One hundred and sixteen subjects participated in the study. PF was assessed using the Senior Fitness Test (SFT) and hand grip strength (HGS). HRQOL was assessed using eight dimensions provided by the SF-12v2 questionnaire. Binary multivariate logistic regression models were carried out considering the potential influence of confounder variables. RESULTS: Non-adjusted models, indicated that subjects with better performance in arm curl test (ACT) were more likely to score higher on vitality dimension (OR > 1) and those with higher HGS were more likely to score higher on physical functioning, bodily pain, vitality and mental health (OR > 1). The adjusted models consistently showed that ACT and HGS predicted a favorable perception of vitality and mental health dimensions respectively (OR > 1). CONCLUSIONS: HGS and ACT have a predictive value for certain dimensions of HRQOL.

[Effects of small-sided exercises on body composition and maximal oxygen uptake in adolescents]. / Efecto de los juegos reducidos en la composición corporal y la condición física aeróbica en un grupo de adolescentes escolares.

BACKGROUND: The regular practice of physical activity contributes to weight control and improves maximal oxygen uptake (VO2max), socialization and quality of life. AIM: To determine the effect of moderate-to-vigorous physical activity on body composition and VO2max in a group of overweight school-age males. MATERIAL AND METHODS: We studied fifty-five overweight males aged 15.6 ± 0.7 years. Participants were divided in two groups (experimental and control groups). The intervention in the experimental group was the practice of small-sided games during 60 minutes, two days per week and during 11 weeks. At baseline and the end of the intervention, body composition was measured using bioimpedance and VO2max was calculated using the Course Navette test. RESULTS: A 7% reduction in the percentage of body fat and a 9% increase in VO2max were observed in the experimental group (p < 0.01). No changes were recorded in the control group. CONCLUSIONS: Eleven weeks of small-sided exercises performed twice per week increased VO2max and reduced fat mass in overweight adolescents.

[Association of grip strength with gender age and handedness in 116 older people]. / Fuerza prensil de mano y su asociación con la edad, género y dominancia de extremidad superior en adultos mayores autovalentes insertos en la comunidad: Un estudio exploratorio.

BACKGROUND: Hand grip strength could be influenced by gender, age and handedness. AIM: To describe differences in grip strength for age, gender and upper extremity handedness in non-disabled community-dwelling older adults. MATERIAL AND METHODS: We studied 47 males aged 72.3 ± 5.6 years and 69 females 72.4 ± 6.0 years who were divided in two age groups (65-70 and ≥ 71 years old). Grip strength was determined by a standardized protocol using a hand dynamometer. RESULTS: There was an inverse correlation between grip strength and age in both hands only among men (p ≤ 0.05). When analyzing both genders, there was a significant inverse correlation between grip strength and age only in the dominant hand (p ≤ 0.05). Strength was higher in the dominant hand in both genders (p ≤ 0.05). It was also higher in men, compared to women in the two age groups studied (p ≤ 0.05). CONCLUSIONS: Grip strength is higher in men than women, it decreases with age and is higher in the dominant hand.

Intra-session reliability of isometric muscle strength of the bilateral standing press in female handball players.

Background: Systematizing reliable protocols and procedures for strength assessment in handball has allowed for a more thorough kinetic analysis and increased precision in detecting training-induced changes in muscular strength. The evaluation of upper limb strength with a bilateral standing press (BSP) exercise in handball players approximates blocking actions in the defensive phase, pushing and fixation. Aim: The aim of this study was to analyze the relative and absolute reliability of intra-session comparisons in an isometric peak muscle strength protocol in a bilateral standing press (BSP) exercise among female handball players. Methods: Sixteen young female handball players at an international level, aged between 22 ± 4 years, with no prior experience in using functional electromechanical dynamometers (FEMD) participated in this study. The participants initiated the assessment of maximum isometric force in a bipedal stance with a forward projection of the dominant foot between 20 and 30 cm. The knees were kept semi-flexed, and the hip extension of the non-dominant limb ranged from 15 to 20°. Bilateral anterior push of the upper limb was performed with shoulder abduction and elbow flexion at 90°, maintaining a pronated hand position. Participants were instructed to exert three sets of maximal force for 5 s in BSP exercise. Relative reliability was assessed using the model intraclass correlation (ICC) and absolute reliability was assessed using the coefficient of variation (CV) and standard error of measurement (SEM). For this study, the parameters of maximum and mean muscle strength were considered. Results: The results demonstrated high relative reliability (ICC 0.93-0.97) and absolute reliability (SEM 0.19-2.79) y (CV 4.78-9.03) for both mean force and peak force, with no significant differences between the sets (p > 0.05), indicating a negligible effect size (0.01-0.12). Conclusion: The mean and peak isometric muscle strength for the BSP exercise controlled with FEMD in female handball players exhibits high relative and absolute reliability between series.

Effect of sit-to-stand-based training on muscle quality in sedentary adults: a randomized controlled trial.

The aim of this study was to compare the effects of sit-to-stand (STS) training programs with 5 vs. 10 repetitions on muscle architecture and muscle function in sedentary adults. Sixty participants were randomly assigned into three groups: five-repetition STS (5STS), 10-repetition STS (10STS), or a control group (CG). Participants performed three sets of five or 10 repetitions of the STS exercise three times per week for 8 weeks. Before and after 8 weeks, all groups performed ultrasound measures to evaluate muscle thickness (MT), pennation angle (PA), and fascicle length (FL), and the five-repetition STS test to estimate the relative STS power and muscle quality index (MQI). After 8 weeks, both experimental groups improved MQI (40-45%), relative STS power (29-38%), and MT (8-9%) (all p < 0.001; no differences between the 5STS vs. 10STS groups). These improvements in both groups resulted in differences regarding the CG, which did not present any change. In addition, only the 5STS group improved PA (15%; p = 0.008) without differences to the 10STS and CG.This suggests that STS training is time-effective and low-cost for improving muscle function and generating adaptations in muscle architecture.

Test-Retest Reliability of the Functional Electromechanical Dynamometer for Squat Exercise.

BACKGROUND: the main objective of this study was to evaluate the test-retest reliability of two different functional electromechanical dynamometry (FEMD)-controlled squat training protocols. METHODS: twenty-eight healthy young adults volunteered to participate in this study. They attended the laboratory on four different days and performed four sessions: two of three sets of 12 repetitions at 75% 1RM and two of three sets of 30 repetitions at 50% 1RM. The range of movement (ROM), mean dynamic strength (MDS), peak dynamic strength (PDS), mean velocity (MV), peak velocity (PV), mean potency (MP), peak potency (PP), work (W), and impulse (I) were recorded. To evaluate the reliability of FEMD, the intraclass correlation coefficient (ICC), standard error of measurement (SEM), and coefficient of variation (CV) were obtained. RESULTS: reliability was very high for ROM (CV: 3.72%, ICC: 0.95), MDS (CV: 1.09%, ICC: 1.00), PDS (CV: 1.97%, ICC: 1.00), and W (CV: 4.69%, ICC: 1.00) conditions at 50% 1RM and for ROM (CV: 3.90%, ICC: 0.95), MDS (CV: 0.52, ICC: 1.00), PDS (CV: 1.49%, ICC: 0.98), and W (CV: 4.14%, ICC: 1.00) conditions at 75% 1RM and high for the rest of variables at 50 and 75% 1RM. CONCLUSIONS: this study demonstrates that FEMD is a reliable instrument to measure ROM, MDS, PDS, MV, PV, PV, MP, MP, W, and I during both squat protocols (50 and 75% 1RM) in healthy young adults.

Dynamometric Strength Profile of Hip Muscles in Youth Soccer Players.

BACKGROUND: Soccer is the most widely practiced sport in the world, demanding high-speed activities such as jumps, sprints and changes of direction. Therefore, having optimal levels of muscle strength improves performance and reduces the injury rate. OBJECTIVES: The objectives of our study were (i) to determine the dynamometric profile of hip muscle strength in young soccer players by position, evaluated at different isokinetic speeds, (ii) to describe the conventional and functional unilateral muscle strength ratios, (iii) to analyze the bilateral balance. METHODS: Thirty-seven male soccer players (age 17.02 ± 0.92 years) participated in the study. Strength assessment was performed with a functional electromechanical dynamometer, and concentric and eccentric strength of abductors, adductors, extensors and hip flexors were measured bilaterally at 0.5 m/s and 1 m/s. RESULTS: For eccentric right hip abduction at 0.5 m/s, defenders are significantly stronger than midfielders (p = 0.013) and stronger than forwards (p = 0.140). For eccentric right hip adduction at 0.5 m/s, defenders are significantly stronger than midfielders (p = 0.005) and stronger than forwards (p = 0.253), as for eccentric right hip adduction at 1 m/s, defenders are significantly stronger than midfielders (p = 0.014) and stronger than forwards (p = 0.084). There is a significant effect for the conventional strength ratio of left abduction/adduction at 1 m/s. The conventional strength ratio of forwards is significantly higher than that of defenders (p = 0.045) and higher than that of midfielders (p = 0.152). CONCLUSIONS: Concentric and eccentric hip strength values differ according to playing position.

Variable Resistance-An Efficient Method to Generate Muscle Potentiation: A Systematic Review and Meta-Analysis.

Variable resistance (VR) is a methodology that has shown good results in developing muscular strength and power. However, no updated information relates to the use of VR as an activation to trigger post-activation performance enhancement (PAPE). The primary objective of this systematic review and meta-analysis was to review and qualitatively describe studies published between 2012 and 2022 that used VR to generate PAPE in muscle power-dominant sports. The secondary objective was to calculate the effect size of the different power outcomes reported in the selected studies. The search was designed following the PRISMA® guidelines for systematic reviews and meta-analyses and performed in the Web of Science (WOS), Scopus, SPORTDiscus, PubMed, and MEDLINE between 2012 and 2022. The methodological quality and risk of bias were evaluated with the Cochrane Collaboration tool. The main variables were the throwing speed, time in sprint tests, and jump height. The analysis was conducted with a pooled standardized mean difference (SMD) through a Hedges' g test (95% CI). Twenty-two studies were included in the systematic review and ten in the meta-analysis, revealing a trivial effect for throwing speed (SMD = 0.06; CI = 95%: -0.23-0.35; p = 0.69), a small effect for the time in sprint tests (SMD = -0.37; CI = 95%: -0.72--0.02; p = 0.04), and a moderate effect for jump height (SMD = 0.55; CI = 95%: 0.29-0.81; p ˂ 0.0001). All forms of VR used for neuromuscular activation effectively triggered PAPE. Specifically, the results showed that activation with VR generates performance increases in time, in sprint tests and jump height, and a trivial effect in throwing tests (speed and distance).

Males Have a Higher Energy Expenditure than Females during Squat Training.

The main objective of this study was to determine the differences in energy expenditure (EE) according to sex during and after two different squat training protocols in a group of healthy young adults. Twenty-nine Sports Sciences students volunteered to participate in this study. They attended the laboratory on four different days and completed four sessions: two sessions with 3 sets of 12 repetitions at 75% of their one-repetition maximum (RM) and two sessions with 3 sets of 30 repetitions at 50% of their 1RM. Energy expenditure was evaluated using an indirect calorimeter. Males consistently demonstrated higher EE in all sessions and intensities. The linear regression model identified a significant association between sex, BMI, and total EE across all sessions and intensities. In conclusion, males exhibited higher EE in both protocols (50% and 75% of 1RM) throughout all sessions. Furthermore, sex and BMI were found to influence EE in healthy young adults. Therefore, coaches should consider sex when assessing EE, as the metabolic response differs between males and females.

Effects of Exergames and Conventional Physical Therapy on Functional Physical Performance in Older Adults: A Randomized Controlled Trial.

Objective: To evaluate the effects of exergames added to a conventional physical therapy (CPT) program on functional fitness and dynamometric muscle performance for the sit-to-stand (STS) maneuver in older adults and to compare their results concerning a CPT-only intervention. Materials and Methods: Fifty independent older adults were randomly assigned to CPT and exergames (CPT+ExG group; n = 25; age = 71.8 ± 6.8 years) or CPT alone (CPT group; n = 25; age = 71.3 ± 7.4 years). CPT was performed twice a week (60 min/session) for 8 weeks. The CPT+ExG group added exergames for 30 minutes in each session. The Senior Fitness Test was applied, considering the 30-second chair stand test as the primary outcome. Additionally, dynamometric muscle performance during the STS maneuver was assessed. Results: The CPT+ExG group improved the 30-second chair stand (lower body strength), back scratch (upper body flexibility), and 8-foot up-and-go (agility/dynamic balance) tests (all P < 0.05). Both groups improved the kinetic dynamometric variables peak force, peak power, and total work (all P < 0.05). Also, both groups improved the 30-second arm curl test (upper body strength) (P < 0.05), although the increase was higher in the CPT+ExG group compared with the CPT group (time × group; P < 0.05). Conclusion: Adding exergames to a CPT program only significantly increases upper limb strength compared with CPT alone. The findings of this study have implications for the design of future exergame interventions focused on improving STS maneuver performance in older adults.

Exploration of the Shoulder Internal Rotation's Influence on Throwing Velocity in Handball Players: A Pilot Study.

The main objective of this study was to test the relationship between shoulder internal rotation strength and standing throwing velocity. A repeated measures cross-sectional study was conducted with 20 professional handball players (mean ± SD; age: 19.28 ± 2.55 years, weight: 81.52 ± 9.66 kg, height: 185 ± 6 cm, BMI: 23.74 ± 1.69). The participants were instructed to perform eight standing throws from the 7 m line of the handball court at maximum velocity to calculate the mean and maximum throwing velocity. An incremental test was performed to calculate the repetition maximum (1-RM) of internal rotation shoulder strength. A Pearson's correlation analysis with a 95% confidence interval (95% CI) was performed to determine whether correlations existed between dominant arm internal rotation strength characteristics and maximum and mean ball-throwing velocity. There is no correlation between the internal rotation strength of the throwing shoulder and the velocity of the ball in the standing handball throw.

Time-Motion Analysis by Playing Positions of Male Handball Players during the European Championship 2020.

The aim of this study was to analyze time-motion characteristics of elite male handball players during the last European Championship 2020. A total of 414 players from 24 national teams were analyzed during 65 matches using a local positioning system (LPS) for the first time in a European Championship. Players (n = 1865) covered significantly (p < 0.001; ES = 0.48) more total distance in offense (1217.48 ± 699.33 m) and in all locomotion categories (p < 0.001) than in defense (900.96 ± 538.95 m), with a similar average total time on court (13.40 ± 8.19 min in offense and 13.27 ± 8.59 min; p > 0.05). The running pace was significantly higher in offense 96.53 ± 22.57 m/min than in defense 82.72 ± 43.28 m/min (p < 0.001; ES = 0.47). By playing positions, the Left Wing players covered significantly (p < 0.001) higher distances (2547.14 ± 1309.52) and showed longer playing time (32.08 ± 17.01). Center Back was the playing position that showed the highest global running pace (98.34 m/min). Players with higher running pace in offense (p < 0.001) were Left Backs (105.95 ± 25.20) and the Center Backs in defense (95.76 ± 48.90). There were no significant differences between winners and losers or between top ranked and lower ranked teams in terms of time played, distance covered, and running pace. Specific physical conditioning is necessary to maximize performance and minimize fatigue when performing in long tournaments.

Test-retest reliability of a functional electromechanical dynamometer on swing eccentric hamstring exercise measures in soccer players.

BACKGROUND: The use of a functional electromechanical dynamometer (FEMD) has been proposed as a valid and effective tool to evaluate specific movement patterns. The aim of this study was to determine the reliability of FEMD on swing eccentric hamstring exercise (SEHE) measures in soccer players. METHODS: Nineteen federated male soccer players (20.74 ± 4.04 years) performed the SEHE at three different isokinetic velocities (20-40-60 cm/s). These evaluations were conducted in four sessions, two for familiarization and two for registration. The average and maximum load (N) of the three isokinetic velocities was calculated from the values obtained from the FEMD (Dynasystem®, Bangalore). RESULTS: The main results of this research showed that the reliability was high for the average load in the condition of 40 cm/s, presenting the highest ICC value (0.94). For maximum load, reliability was high in the condition of 20 cm/s. The manifestation of the most reliable load was the maximum load (ICC = 0.91-0.87). CONCLUSIONS: FEMD (Dynasystem®, Bangalore) is a reliable device to evaluate the eccentric strength of the hamstring muscles in soccer players.

Changes in Muscle Oxygen Saturation Measured Using Wireless Near-Infrared Spectroscopy in Resistance Training: A Systematic Review.

Background: This study aimed to report, through a systematic review of the literature, the baseline and final reference values obtained by near-infrared spectroscopy (NIRS) of muscle oxygen saturation (SmO2) during resistance training in healthy adults. Methods: Original research studies were searched from four databases (Scopus, PubMed, WOS, and SportDiscus). Subsequently, three independent reviewers screened the titles and abstracts, followed by full-text reviews to assess the studies' eligibility. Results: Four studies met the inclusion criteria, data were extracted and methodological quality was assessed using the Downs and Black scale. Muscle oxygen saturation (% SmO2) during reported muscle strength exercises showed a decreasing trend after a muscle strength protocol; that is, before the protocol (range = 68.07-77.9%) and after (range = 9.50-46.09%). Conclusions: The trend of the SmO2 variables is to decrease after a muscle strength protocol. Studies are lacking that allow expanding the use of these devices during this type of training.