"You Are Not Wrong About Getting Strong:" An Insight Into the Impact of Age Group and Level of Competition on Strength in Spanish Football Players.

OBJECTIVE: This study aimed to compare the maximum and rapid force production of Spanish football players and explore the differences between age group and level of competition. METHODS: A cross-sectional study was developed to evaluate the peak force (PF), relative PF, and rate of force development over 250 ms (RFD0-250) during the isometric midthigh pull between groups of football players based on age group (senior vs junior) and level of competition (national vs regional). Using a portable isometric rig, 111 football players performed 2 isometric midthigh-pull trials on a force plate. Two-way analysis of variance with Bonferroni post hoc correction was applied, and statistical significance was set at P ≤ .05. The PF, relative PF, and RFD0-250 0, 25, 50, 75, and 100 percentiles were also calculated and descriptively reported, separated by age group and level of competition. RESULTS: The analysis of variance revealed a significant main effect of the level of competition for the PF (P < .001), relative PF (P = .003), and RFD0-250 (P < .001). There was a significant main effect of age group for the PF (P < .001). There was a significant interaction effect of the age group × level of competition for relative PF (P = .014). National players were stronger than regional players on the PF and RFD0-250 (P < .001). Senior players were stronger than junior players for the PF (P < .001). CONCLUSIONS: Maximum and rapid force production are crucial for Spanish football players as they progress in both level of competition and age group. Practitioners should encourage young football players to prioritize strength development to improve their athletic performance.

Potential Benefits of a Single Session of Remote Ischemic Preconditioning and Walking in Sedentary Older Adults: A Pilot Study.

Ischemic preconditioning (IPC) has shown positive effects in endurance-type sports among healthy young individuals; however, its effects in endurance-type exercises in older adults have not been explored. We aimed to examine the acute effects of a single session of IPC prior to an endurance-type exercise on cardiovascular- and physical-function-related parameters in sedentary older adults. A pilot study with a time-series design was carried out. Nine participants were enrolled consecutively in the following intervention groups: (i) SHAM (sham IPC + walking) and (ii) IPC (IPC + walking) groups. The main outcomes were resting systolic (SBP) and diastolic (DBP) blood pressure, heart rate (HR), peripheral oxygen saturation (SpO2), maximum isometric voluntary contraction (MIVC), endurance performance, and perceived fatigue. After the intervention, the IPC group showed a significant reduction in SBP, whereas SpO2 decreased in the SHAM group. The IPC group maintained quadriceps MIVC levels, whereas these levels dropped in the SHAM group. No changes in DBP, resting HR, endurance, or fatigue in any group were observed. These findings are of interest for the promotion of cardiovascular and physical health in older people.

Effects of Hypopressive Exercise on Posterior Back Chain Kinematics and Pulmonary Function in Professional Female Basketball Players.

CONTEXT: Hypopressive exercise (HE) has been used as an alternative lumbo-pelvic injury prevention program and claimed to be a means of respiratory and flexibility improvement. However, the possible effects of HE on athletic populations and physical performance remain unclear. OBJECTIVE: Examine the effects of a HE program on posterior back chain kinematics, thoracic mobility, pulmonary function, and lower lumbar pain in female basketball players over an 8-week training period. DESIGN: Prospective (1) baseline, (2) midpoint (4 wk), and (3) after 8 weeks. SETTING: Sports field. PARTICIPANTS: A total of 17 professional female basketball players (mean age 20.7 y, SD: 3.50; body mass index, 21.71, SD: 1.69). INTERVENTION: Participants performed 8 HE weekly sessions of 30 minutes. MAIN OUTCOME MEASURES: Back chain kinematics was assessed with the sit and reach and finger to floor test, and back pain was assessed through numerical rating scale. Respiratory parameters were assessed by spirometry and through thoracic mobility. RESULTS: The analysis of variance revealed significant differences between the 3 measurement periods for thoracic mobility (P > .01); forced expiratory volume in the first second (P < .05) while no statistical differences were found for the rest of spirometry outcomes. Significant differences were also revealed between baseline and after the intervention for the sit and reach test (P > .01), peak expiratory flow (P = .01), and forced expiratory volume in the first 25 seconds (P = .04). Also, significant differences between weeks were found in levels of lumbar pain (P = .003) and the finger to floor test (P = .002). CONCLUSIONS: These preliminary findings suggest that a HE program can improve posterior back chain and chest wall kinematics as well as lower lumbar pain levels. However, no gains seem to be observed for the majority of pulmonary variables except for peak expiratory flow and forced expiratory volume in the first seconds.

Integrative Neuromuscular Training Enhances Physical Fitness in 6- to 14-Year-Old Rugby Players.

ABSTRACT: Alonso-Aubin, DA, Picón-Martínez, M, Rebullido, TR, Faigenbaum, AD, Cortell-Tormo, JM, and Chulvi-Medrano, I. Integrative neuromuscular training enhances physical fitness in 6- to 14-year-old rugby players. J Strength Cond Res 35(8): 2263-2271, 2021-The purpose of this study was to assess the effects of an 8-week integrative neuromuscular training (INT) program on physical fitness measures in young rugby players. A sample of 138 male rugby players (age range, 6-14 years) was divided into 5 age-related groups: group 1 (G1) (n = 20; age, 7.05 ± 0.58), group 2 (G2) (n = 27; age, 8.57 ± 0.49), group 3 (G3) (n = 31; age, 11.02 ± 0.56), group 4 (G4) (n = 33; age, 13.12 ± 0.58, and group 5 (G5) (n = 27; age, 14.85 ± 1.53 and additionally into 2 game position groups: forwards (FOR) (n = 69) and backs (BAC) (n = 69). Physical fitness measures included the Functional Movement Screen (FMS), dominant and nondominant hand-to-eye coordination, sprint capacity, core muscular endurance, and lower- and upper-body power. Integrative neuromuscular training (INT) included progressive strength, coordination, and speed exercises performed twice per week for 20 minutes. Following INT, significant improvements in selected age-related groups (p < 0.01) were found in total FMS score G3 (effect size [ES] = 0.47), G4 (ES = 0.88), and G5 (ES = 0.58); dominant hand-to-eye coordination G1 (ES = 1.48), G2 (ES = 0.71), G3 (ES = 0.55), G4 (ES = 1.47), and G5 (ES = 1.15), nondominant hand-to-eye coordination G2 (ES = 0.74), G4 (ES = 1.34), and G5 (ES = 1.09); lower-body power G2 (ES = 0.44), G4 (ES = 0.39), and G5 (ES = 0.43); core muscular endurance G1 (ES = 0.82), G3 (ES = 0.68), and G4 (ES = 1.04); upper-body power G2 (ES = 0.53); and sprint capacity G4 (ES = 0.69). Significant improvements were also found between player's positions for all tests. These findings indicate that a progressive INT program can enhance functional movement abilities and selected physical fitness measures in young rugby players regardless of game position and age.

Acute Effects of Resistance Training with Blood Flow Restriction on Achilles Tendon Thickness.

The Achilles tendon is one of the strongest and thickest tendons of the human body. Several studies have reported an immediate decrease in Achilles tendon thickness after a single bout of resistance training. However, the effects of blood flow restriction training on Achilles tendon thickness have not been investigated. The purpose of this study was to investigate the acute effects of different regimens of resistance training on Achilles tendon thickness. Fiftytwo participants (27.3 ± 7 years; 177.6 ± 11 cm; 72.2 ± 13.7 kg) were randomly allocated into one of the three groups: low-intensity exercise without (LI, n = 13) and with blood flow restriction (LI-BFR, n = 24), and high-intensity exercise (HI, n = 15). Participants from LI and LI-BFR groups performed four sets (1 x 30 + 3 x 15 reps) at 30% 1RM, while the HI group performed four sets (1 x 30 with 30% 1RM + 3 x 10 reps with 75% 1RM). All groups performed a plantar flexion exercise. For the LI-BFR group, a blood pressure cuff was placed on the dominant calf and inflated at 30% of the individual´s occlusion pressure (47.6 ± 19.8 mmHg). Sonographic images of Achilles tendon thickness were taken at pre, immediately after, 60 min and 24 h following acute bouts of exercise. Achilles tendon thickness was significantly reduced immediately after, 60 min and 24 h post-LI-BFR exercise (pre: 4.4 ± 0.4 mm vs. IA: 3.8 ± 0.4 mm vs. 60 min: 3.7 ± 0.3 mm vs. 24 h: 4.1 ± 0.3 mm; p < 0.001), whereas Achilles tendon thickness was unchanged for HI and LI groups (p > 0.05). These results suggest that blood flow restriction training may be an effective strategy to stimulate a positive response in Achilles tendon thickness.

Squat and Bench Press Force-Velocity Profiling in Male and Female Adolescent Rugby Players.

ABSTRACT: Alonso-Aubin, DA, Chulvi-Medrano, I, Cortell-Tormo, JM, Picón-Martínez, M, Rial-Rebullido, T, and Faigenbaum, AD. Squat and bench press force-velocity profiling in male and female adolescent rugby players. J Strength Cond Res 35(2S): S44-S50, 2021-Power development is critical for enhancing rugby performance because there is a close relationship between power and sport-specific skills. The aim of this study was to examine the force-velocity profiling generated by adolescent rugby players in the squat and bench press exercises and to compare sex-related differences. Subjects were 46 men (age: 14.48 ± 1.31 years; body height: 1.65 ± 0.09 m; and body mass: 58.07 ± 13.01 kg) and 41 women (age: 14.93 ± 2.76 years; body height: 1.63 ± 0.12 m; and body mass: 59.23 ± 12.66 kg) who were recruited from a national amateur rugby league team. Maximal strength, power, and velocity were assessed on the squat and bench press exercises using a Smith Machine and a linear power transducer with intensities ranging from 40 to 80% 1 repetition maximum (1RM) on the squat and 50-80% 1RM on the bench press. 1 repetition maximum squat and bench press performance were 104.26 ± 30.83 and 46.97 ± 13.59 kg, respectively, for men and 115.17 ± 41.42 and 45.85 ± 16.71 kg, respectively, for women. The maximum squat power results for men and women were 521.91 ± 298.75 and 591.26 ± 352.69 W, respectively, and the maximum bench press power results for men and women were 190.26 ± 150.54 and 326.16 ± 195.57 W, respectively. Significant sex-related differences (p < 0.001) were found on the squat exercise for maximum (40%), mean (40-50%), and time to maximum velocities (40-80%) as well as time to maximum power (80%). On the bench press exercise, significant sex-related differences (p < 0.001) were found for power and time to maximum velocity (40%-60%-70%-80%). These results may aid in the design of strength and conditioning programs for adolescent rugby players by targeting training prescriptions toward enhancing strength or velocity.

Métodos de evaluación de la composición corporal: una revisión actualizada de descripción, aplicación, ventajas y desventajas / Methods of assessment of body composition: an updated review of description, application, advantages and disadvantages

El estudio de la composición corporal es un tema de interés creciente que puede ser utilizado tanto para la investigación como para fines clínicos. Para los profesionales de las ciencias de la salud es importante conocer las características de los diferentes métodos de evaluación y análisis de la composición corporal, ya que cambios en esta guardan relación directa con la salud y el riesgo de enfermedades. Actualmente, los métodos de análisis de la composición corporal son divididos en tres grupos, donde están el directo, los indirectos y los doblemente indirectos. El método directo es la disección de cadáveres. Entre los indirectos encontramos la tomografía axial computarizada, la resonancia magnética nuclear (RMN), la absorciometría dual de rayos X y la plestimografía; y en lo referente a los métodos doblemente indirectos destacan la antropometría y la impedancia bioelectrica. Asi, este trabajo tiene como objetivo revisar los métodos mas utilizados para el análisis de la composición corporal, describiéndoles, analizando sus aplicaciones, ventajas y desventajas. Se llevo a cabo una búsqueda de artículos en las bases de datos PubMed, Web of Science, Scopus, SportDiscus y Google Academico. Las palabras usadas fueron, body composition, body mass, body fat, muscle mass, fat mass, measurement, assessment y evaluation, aisladas o combinadas, y sus respectivos sinónimos en castellano y portugués. Fueron encontrados 221 artículos, de los cuales fueron seleccionados 59 para esta revisión. Se concluye que los diferentes métodos para evaluar la composición corporal presentan ventajas y desventajas, que deben ser analizados cuando se elige el método a ser empleado, para intentar minimizar sus desventajas y potencializar sus ventajas (AU)

The study of body composition is a topic of growing interest that can be used both for research and for clinical purposes. For professionals of health sciences is important to know the characteristics of the different methods of evaluation and analysis of body composition because, it changes are directly related to health and disease risk. Currently, methods of analysis of body composition are divided into three groups, which are direct, indirect and double indirect. The direct method is the dissection of cadavers. Indirect find computed tomography, magnetic resonance imaging, dual X-ray absorptiometry and plethysmography and in terms of the doubly indirect methods include anthropometry and bioelectrical impedance. Thus, this paper is aimed to review the most used for analysis of body composition by describing, analyzing their applications, advantages and disadvantages methods. Was conducted a search of article in databases PubMed, Web of Science, Scopus, SportDiscus and Google Scholar. The words used were, body composition, body mass, body fat, muscle mass, fat mass, measurement, assessment and evaluation, isolated or combined and their alternatives in Castilian and Portuguese. Were selected articles that were in English, Castilian and portuguese. They were found 221 articles, of which 59 were selected for this review. It is concluded that the different methods for assessing body composition have advantages and disadvantages, which should be analyzed when choosing the method to be used to try to minimize the disadvantages and empower its advantages (AU)