Effects of different resistance training programmings on the relative strength, body composition, anthropometric variables, and metabolic risk of elderly women.

The purpose of this study was to analyze the effect of two different programming models of resistance training (RT) on metabolic risk, anthropometric variables, and relative strength in elderly women. The research was a prospective and comparative longitudinal study with a non-probabilistic random sample. Twenty-two elderly women (64 ± 3 years) was divided into two experimental groups being the Linear programming (LP, n = 12) and Daily undulatory programming (DUP, n = 10), with 3 sessions/week for 12 weeks. Submaximal strength (10RM) was evaluated in the horizontal leg press (HL), pulldown (PD), leg curl (LC), vertical bench press (BP), and leg extension (LE). Anthropometric variables, food intake (R24h) and submaximal strength (10RM) was analyzed. Participants were initially classified as overweight or obese evaluated by body mass index (BMI) and percentual of fat mass (%FM) and with moderate to high risk to develop metabolic diseases evaluated by hip-waist ratio (HWR), waist-height ratio (WHR) and waist circumference (WC). There is no change for metabolic risk and anthropometric variables after the intervention period. There was a significant improvement for relative strength accessed by 10RM and body weight (10RM/BW), and lean body mass (10RM/LBM) (p < 0.05), with large or medium effect size for most of variables after 12 weeks of RT. As a conclusion, both programmings increased relative strength after 12 weeks of RT with attenuated change in body composition and metabolic risk in elderly women in both programming groups and all those strategies can be used in elderly women to improve strength.

Translation, cross-cultural adaptation, and validation of the 10-item spine functional index (SFI-10) in the Brazilians with musculoskeletal spine disorders.

PURPOSE: To translate and cross-culturally adapt the Spine Functional Index (SFI) into Brazilian Portuguese (SFI-Br) in individuals with musculoskeletal spine disorders. METHODS: Participants (n=194) answered the Numerical Pain Rating Scale (NPRS), 36-item Short-Form Health Survey (SF-36), Roland-Morris Disability Questionnaire for General Pain (RMDQ-g), and SFI-25 incorporating the SFI-10. Structural validity, from confirmatory factor analysis (CFA), used comparative fit index (CFI), Tucker-Lewis index (TLI), root mean square error of approximation (RMSEA), and chi-square/degrees of freedom (DF). The best structure was considered from the lower values of the Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC). Construct and criterion validity used Spearman's correlation coefficient (rho). Internal consistency used Cronbach's alpha, reliability used intraclass correlation coefficient (ICC2,1), with ceiling and floor effects determined. Error used the standard error of the measurement (SEM) and minimal detectable change, 90% level (MDC90). RESULTS: Adequate fit indices demonstrated an unequivocal one-factor structure only for the SFI-10 (chi-square/DF <3.00, CFI and TLI >0.90, RMSEA <0.08). The SFI-10-Br correlation was high with the SFI-Br (rho=0.914, p<0.001), moderate for the RMDQ-g (rho=-0.78), SF-36 functional capacity domain (rho=0.718) and NPRS (rho=-0.526); and adequate for the remaining SF-36 domains (rho>0.30). Test-retest reliability (ICC2,1=0.826) and internal consistency (alpha=0.864) were high. No ceiling or floor effects were observed, and error was satisfactory (SEM=9.08%, MDC90=25.15%). CONCLUSION: The SFI Brazilian version was successfully produced with the 10-item version showing an unequivocal one-factor structure, high construct and criterion validity, reliability, internal consistency, and satisfactory error. Further research on responsiveness is required.

Frequência e distribuição do gene da α-actinina-3 e sua associação em atletas brasileiras de voleibol / Frequency and distribution of the α -actinin-3 gene and its association in brazilian volleyball athletes

Introduction: The ACTN3 gene encodes the α-actinin-3 protein in the Z lines of the sarcomere, which anchors the actin protein in the contractile apparatus, present exclusively in type II muscle fibers, presenting greater glycolytic capacity, which is essential for sports with high-energy actions. intensity and short duration as is the case with Volleyball. Objective: To verify the frequency and distribution of the ACTN3 gene, RR and RX genotypes that express α-actinin-3 (EX α-actinin-3), and XX genotype that do not express α-actinin-3 (NE α-actinin-3) and its association with Brazilian volleyball athletes. Materials and Methods: Nine-seven (97) athletes from the women's volleyball super league took part in the study. Body mass, height and age were evaluated to characterize the sample. Salivary samples were analyzed using (PCR) in real time, to determine the genotypes, and, to verify the association of the genotype with the status of volleyball athlete in the three categories (National Teams, Brazilian National Team and Brazilian Olympic Team), the test was carried out Chi-square of independence (χ²). To obtain the odds ratio of the outcome, a log linear regression analysis was performed. All tests were carried out using the JAMOVI 2.4 (2023) statistical software. Results: Among the athletes in the sample competing in the National Teams competition, 91.8% have the EX-α-actinin-3 genotype. When we consider Brazilian National Team competitions, 93.7% have the EX-α-actinin-3 genotype. Athletes who play for the Brazilian Olimpic Team, 100% of the sample have the EX-α-actinin-3 genotype. Considering that in the world population, the frequency is 80%, it is possible to verify that as you approach the athletes who participate in the women's team there is a greater participation of athletes with the EX-α-actinin-3 genotype. Furthermore, there was an association between the genotypes that EX α-actinin-3 and the National category, with the status of elite athlete, where (χ²) obtained the p value (0.023) and the rate ratio (2.71) for the outcome of the genotypes (EX α-actinin-3) being elite athletes. Conclusion: The athlete's genetic characteristics, environment, nutrition, physical, technical and tactical preparation are some of the factors that contribute to sports performance. However, the results of the present study suggest that athletes with RR and RX genotypes that express α-actinin-3, present in type II muscle fibers, seem to confer an advantage when playing high-performance volleyball.

Anterior Knee Pain Scale (AKPS): structural and criterion validity in Brazilian population with patellofemoral pain.

PURPOSE: To identify the best internal structure of the Brazilian version of the Anterior Knee Pain Scale (AKPS), comparing different instrument structures (structural validity) and correlating the scores of the versions (criterion validity). METHODS: We included Brazilian volunteers, aged ≥ 18 years, with patellofemoral pain (PFP) for at least 3 months. We used the confirmatory factor analysis and considered the following fit indices: chi-square/degrees of freedom (DF), comparative fit index (CFI), Tucker-Lewis index (TLI), root mean square error of approximation (RMSEA). We considered the structure with the lowest values of the Akaike information criterion (AIC), sample size adjusted Bayesian information criterion (SABIC), and assessed criterion validity using Pearson correlation coefficient (r) to correlate the long and short versions. RESULTS: The study included 101 participants, mostly women (65.3%), young adults (~ 31 years old), overweight (BMI > 25 kg/m2), incomplete higher education (37.6%), and physically active (64.4%). The original 1-domain, 13-item structure showed adequate fit indices (chi-square/GL < 3.00, TLI and CFI > 0.90, and RMSEA < 0, 08). However, items 11 and 12 had a factorial load of less than 0.23. Therefore, we excluded items 11 and 12 and found adequate fit indices (chi-square/GL < 3.00, TLI and CFI > 0.90, and RMSEA < 0, 08) and lower AIC and SABIC values. We observed a correlation coefficient above the acceptable cutoff of 0.70 (r = 0.966, p-value < 0.001) between the versions. CONCLUSION: The 11-item AKPS (without items 11 and 12) is the version with the most adequate internal structure and correlates satisfactorily with the long version of the instrument.

Linear and undulating resistance training programming induce similar outcomes on physical fitness in elderly women / Programações linear e ondulatória do treinamento de força induzem a mesmos resultados na aptidão física em mulheres idosas

Abstract The aim of the present study was to analyze the effect of two different types of resistance training programming (linear and daily undulating) on submaximal strength and functional capacity in elderly women. Twenty-two participants (64 ± 3 years) were randomly assigned to 2 training groups: linear programming (LP; n=12) and daily undulating programming (DUP; n =10). Functional capacity and submaximal strength (10RM) were analyzed before and after 12 weeks of resistance training. The results demonstrated improvement on strength and functional capacity after the resistance training period (p ≤ 0.05), except for the Bench Press (p = 0.30), for both groups DUP and LP. The Effect Size was, respectively, high for DUP (timed up and go test = -2.07, and timed sit test= 4.69), and high for LP (horizontal leg press = 2.35). For all other results, the effect size was trivial or small. No statistical difference was observed between programming models. The LP and DUP trainnings have similar results in increasing submaximal muscle strength in elderly women inexperienced in RT after 12 weeks of intervention (p ≤ 0,05). However, DUP appears to be more effective in increasing functional capacity. In practice, the professional can use both the LP and the DUP to improve the level of fitness in the early stages of training in this population. However, when the goal of programming is to increase functional capacity, DUP can be prioritized.

Resumo O objetivo do presente estudo foi analisar o efeito de dois tipos diferentes de programação do treinamento de força (linear e ondulatório diário) na força submáxima e na capacidade funcional de mulheres idosas. Vinte e duas participantes (64 ± 3 anos) foram randomizados em 2 grupos experimentais: programação linear (PL; n=12) e programação ondulatória diária (POD; n=10). A capacidade funcional e a força submáxima (10RM) foram avaliadas antes e depois das 12 semanas de treinamento de força. Os resultados demonstraram melhora da força submáxima e da capacidade funcional após o período de treinamento (p ≤ 0,05), exceto para o exercício supino (p = 0,30), para ambos os grupos POD e PL. Foi encontrado um tamanho de efeito grande para a POD nos testes de sentar e caminhar = -2,07 e teste de sentar e levantar = 4,69, bem como na PL para o exercício leg press horizontal = 2,35. Não foi observada diferença estatística entre os modelos de programação. As programações LP e DUP têm resultados semelhantes no aumento da força muscular submáxima em mulheres idosas inexperientes em TR após 12 semanas de intervenção (p ≤ 0,05). No entanto, o DUP parece ser mais eficaz para aumentar a capacidade funcional. Na prática, o profissional pode usar tanto o LP quanto o DUP para melhorar o nível de condicionamento físico nos estágios iniciais do treinamento nessa população. Porém, quando o objetivo da programação é aumentar a capacidade funcional, o DUP pode ser priorizado.

Possible influences of vitamin D levels on sleep quality, depression, anxiety and physiological stress in patients with chronic obstructive pulmonary disease: a case control study.

This study aimed to evaluate the effect of vitamin D deficiency on sleep quality, depression, anxiety, and physiological stress in patients with chronic obstructive pulmonary disease (COPD). We screened for COPD patients with normal (NorVD) (n=24) and insufficient (InsVD) (n=7) vitamin D levels. The Pittsburgh sleep quality index (PSQI), the Beck anxiety inventory (BAI), the Beck depression inventory (BDI) and the Baevsky's stress index were used for the sleep and psychometric evaluation. The evaluation of sleep quality by PSQI showed that NorVD individuals had higher duration and quality of sleep when compared with the InsVD group. Additionally, the group InsVD presented higher risk of developing sleep quality (OR=6.20; 95% CI=1.334, 29.013; p=0.009). BDI was higher in the InsVD, and this group had a higher risk of developing moderate and severe depression (OR=3.37; 95% CI=0.895, 12.722; p=0.03). The stress index indicated higher values in the InsVD in relation to the NorVD group (InsVD=24±0.8 vs. NorVD=16±0.9), and the group InsVD showed higher risk of developing high and very high physiological stress (OR=7.70; 95% CI=1.351, 43.878; p=0.01). The stress and sleep quality effects were negatively correlated with vitamin D levels. Insufficient levels of vitamin D negatively affect sleep quality and psychometric variables.

Mechanisms of muscle stretching exercises for reduction of low back pain: narrative review / Mecanismos de exercícios de alongamento muscular para redução de dor lombar: revisão narrativa

ABSTRACT BACKGROUND AND OBJECTIVES: Stretching exercises are present in physical training and muscle rehabilitation programs. Within the context of rehabilitation of patients with low back pain (lombalgy), there is still a gap about the mechanisms that these exercises should reduce pain and disability in these patients. The aim of this study was to investigate what are the possible mechanisms through which muscle stretching exercise could reduce pain in individuals with chronic low back pain.CONTENTS: Pain in the lumbar region is one of the most disabling pains when it comes to limitations for daily functions, so it's necessary to investigate alternatives that provide relief for these patients. As the cause of non-specific chronic low back pain is multifactorial, the treatment of the pathology occurs mainly to reduce the sensation of pain. As an alternative, the flexibility training through stretching exercises can be efficient because they generate biomechanical and sensory changes, which would result in an analgesic effect. Additionally, it's still possible that these two effects occur together to explain the reduction in low back pain after performing stretching exercises. CONCLUSION: There is theoretical basis in the literature to support the performance of stretching exercises as a non-pharmacological strategy for the treatment of chronic low back pain. Biomechanical and neurophysiological mechanisms can be pointed out to explain these benefits.

RESUMO JUSTIFICATIVA E OBJETIVOS: Exercícios de alongamento estão presentes em programas de treinamento físico e reabilitação muscular. Dentro do contexto da reabilitação de indivíduos com dor na região lombar (lombalgia), ainda existe uma lacuna sobre os mecanismos pelos quais esses exercícios reduzem dor e incapacidade nesses pacientes. O objetivo deste estudo foi descrever os possíveis mecanismos pelos quais o exercício de alongamento pode reduzir dor em indivíduos com lombalgia crônica. CONTEÚDO: A dor na região lombar é uma das dores mais incapacitantes quando se trata de limitações para as funções no cotidiano. Por isso, é necessário investigar alternativas que possam proporcionar o seu alívio nesses pacientes. Considerando que a causa da lombalgia crônica não específica é multifatorial, o tratamento desta doença ocorre principalmente na tentativa de reduzir a sensação dolorosa. Como alternativa, o treinamento da flexibilidade por meio de exercícios de alongamento pode agir reduzindo a dor lombar por gerarem alterações biomecânicas e sensoriais que resultam em efeito analgésico. Adicionalmente, ainda é possível que esses dois efeitos possam atuar em conjunto para explicar a redução da dor lombar após a realização de exercícios de alongamento. CONCLUSÃO: Existe suporte teórico na literatura para sustentar a realização dos exercícios de alongamento como estratégia não farmacológica para o tratamento da dor lombar crônica. Mecanismos biomecânicos e neurofisiológicos poderiam ser apontados para explicar tais benefícios.

Effect of Fatigue and Graded Running on Kinematics and Kinetics Parameters in Triathletes.

This study aimed to evaluate the effect of cycling-induced fatigue on subsequent running with different ground inclinations on triathletes. Twenty male triathletes ran on a treadmill at individual speeds, on three inclines: level (0%), 7% uphill (7%), and 7% downhill (-7%). Subsequently, the athletes performed an incremental ramp-to-exhaustion (RTE) protocol on an ergometric bicycle until task failure and repeated the running protocol (POST-RTE). During running and cycling was monitored perceived exertion (RPE) and heart rate (HR). Plantar pressure distribution, peak plantar pressure, total foot area, and ground contact time were measured by an in-shoe sensor. Analysis of variance showed that HR (p=0.001; η2=0.63) and RPE (p=0.001; η2=0.82 large effect) were higher in POST-RTE, without interactions between slopes and fatigue. The heel load showed difference between 0 and 7% and 7 and -7% (p=0.001; η 2=0.44 large effect) with higher value in -7%. The midfoot showed differences between 0 and -7% with higher value in 0% (p=0.03; η 2=0.15 small effect). The contact time showed interactions between fatigue and slopes with a higher value in POST-RTE. Coaches should be aware that training on the uphill and downhill surfaces can alter the plantar load on different foot parts.

Construct validity and reliability of the 2-minute step test in patients with knee osteoarthritis.

OBJECTIVE: To validate and evaluate the intra- and inter-rater reliability of the 2-min step test (2MST) in measuring the functional performance of patients with knee pain associated with osteoarthritis (OA). METHODS: Forty-one patients with knee OA was included. Two examiners assessed the patients at two times with interval between the test and retest from 7 to 14 days. All executions of 2MST were recorded in real time by the examiners and were also recorded by video. The intraclass correlation coefficient (ICC) and 95% confidence interval (CI), standard error of measurement (SEM) and minimum detectable difference (MDD) were used to determine reliability. In the construct validity, we correlate the score of the 2MST with the other instruments used in the study: The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Numerical Pain Scale (NPS), Pain-Related Catastrophizing Thoughts Scale (PCTS) and Chronic Pain Self-Efficacy Scale (PSEQ). The agreement between the face-to-face assessment and the evaluation based on the video record was assessed using the Bland-Altman methodology in the 4 moments of the 2MST. RESULTS: 2MST presented excellent intra- (ICC = 0.94, SEM = 4.47, MDD = 12.40) and inter-rater reliability (ICC = 0.97, SEM = 3.07, MDD = 8.52). The agreement was acceptable between face-to-face assessments and the analyzes performed on video. All instruments showed a statistically significant correlation with 2MST, except the PCTS. A correlation magnitude above 0.50 was found between the 2MST and pain and function domains of the WOMAC, and a correlation magnitude between 0.30 and 0.50 with the joint stiffness domain of the WOMAC, NRPS and PSEQ. CONCLUSION: 2MST proved to be valid for assessing functional capacity in patients with knee OA, with excellent reliability.

Aerobic Training Modulates the Increase in Plasma Concentrations of Cytokines in response to a Session of Exercise.

Acute physical exercise can modulate immune function. For example, acute exercise is known to increase the circulating concentration of cytokines. Exercise is also known to modulate immune function chronically. It is not known whether exercise training can result in training of the immune system. Here, we investigated the effects of six weeks of aerobic training on cytokine responses induced by acute exercise until fatigue. Twelve healthy men performed a fatiguing exercise at the anaerobic threshold (AT) intensity. After the training period, the participants performed another bout of acute exercise at the same duration and intensity of the pretraining situation. The analysis was made at the beginning, end, and at 10, 30, and 60 minutes during the recovery period. Training at AT induced a gain of 11.2% of exercise capacity. Before training, a single bout of acute exercise induced a significant increase in plasma levels of cytokines, including IL-6, TNF-α, sTNFR1, IL-10, CXCL10, BDNF, leptin, resistin, and adiponectin. After six weeks of aerobic training, levels of IL-6, sTNFR1, BDNF, and leptin increased to a lesser extent after an acute bout exercise at the same absolute intensity as the pretraining period. Responses to the same relative exercise intensity were similar to those observed before exercise. These results show that aerobic training is associated with training of acute immune responses to acute exercise until fatigue.

Official matches and training sessions: physiological demands of elite junior badminton players

Abstract Aim: To evaluate the intensity of training and official badminton matches (international championship) in junior elite players. Methods: Twelve elite players from the Brazilian junior national team (6 male and 6 female) were monitored during 19 training sessions and 50 official men's and women's single and double matches in the XXVII Pan-American Junior Games. Subjects underwent an incremental running step test to determine maximal oxygen uptake (VO2max), and an individual relationship between heart rate (HR) and VO2max was established to estimate exercise intensity and oxygen uptake at official matches (OMs) and training sessions. HR was monitored during multi-shuttlecock (MS), technical-tactical (TT), and physical (PS) training methods, as well as during simulated matches (SMs) and OMs. Variables such as %HRmax, HR zones, %VO2max, and energy expenditure were also calculated. Results: OM was the most intense activity monitored for male and female athletes, followed by SM according to %HRmax (86.8 ± 4.1% and 84.4 ± 5.0% for female and male, respectively, in OM vs. 74.6 ± 2.3% and 75.0 ± 5.0% for female and male, respectively, in SM). OM mean energy expenditure was 10.7 ± 0.5 kcal.min-1 for females and 14.9 ± 4.6 kcal.min−1 for males. Conclusion: MS training has less physiological demand and OM presented higher intensity. SM, on the other hand, had the closest physiological demand to an OM.

Seated Single-Arm Shot-Put Test to Measure the Functional Performance of the Upper Limbs in Exercise Practitioners With Chronic Shoulder Pain: A Reliability Study.

OBJECTIVE: To measure the intra- and interrater reliability of the seated single-arm shot-put test (SSPT) in the functional performance of the upper limbs of regular physical exercise practitioners with shoulder pain. METHODS: This is a reliability study. Thirty individuals regularly practicing any sports modality that uses the upper limb effectively for at least 6 months, both sexes, ages between 18 and 30 years, with chronic shoulder pain were included. Chronic shoulder pain was measured by means of the shoulder pain and disability index, numerical rating scale, and catastrophic thoughts about pain scale. Functional performance of the upper limbs was measured by means of SSPT. RESULTS: Excellent intrarater reliability was found, with intraclass correlation coefficient ≥0.93, standard error of the measurement values ≤4.63%, and minimum detectable change values for absolute and normalized score of 45.11 cm and 9.97, respectively. Excellent interrater reliability was found, with intraclass correlation coefficient ≥0.96, standard error of the measurement values ≤3.55%, and minimum detectable change values for absolute and normalized score of 32.29 cm and 7.70, respectively. CONCLUSION: SSPT is a reliable tool for measuring the functional performance of the upper limbs in regular exercise practitioners with chronic shoulder pain.

Effects of puberty on jump and sprint performance in young futsal players / Efeitos da puberdade no desempenho de saltos e sprints em jogadores jovens de futsal / Efectos de la pubertad en el desempeño de saltos y sprints en jugadores jóvenes de futsal

ABSTRACT Futsal is a sport that involves motor actions with high intensity and short duration, especially vertical jumps and sprints, which require fast application of strength and speed. The evaluation and training of these physical capacities is a routine practice of coaches, especially in the base categories, which are the entry point for many children and adolescents aiming for a professional career in futsal. With regard to the training of this public, puberty is a factor that must be considered, as a natural biological process involving several bodily transformations that can influence the performance of these physical capacities, especially considering that the categories are divided by chronological age, which does not always correspond to pubertal age. The objective of this study was to conduct a literature review of body modifications during puberty, and how these can affect the aspects that determine good performance in jumps and sprints. It was verified that this phase is associated with hormonal changes, an increase in muscle mass, and anthropometric aspects, as well as the maturation of the neuromuscular functions and refinement of the more complex motor activities, such as locomotion. Together, these factors can favor the fast application of force, and better performance of these players in terms of motor activities. However, it is important to emphasize that although these factors increase and naturally favor the players' performance in terms of strength and speed, it is a phase in which specific types of training focused on the aspects that determine good performance are fundamental to increase these capacities and diminish other aspects that also occur with the bodily development, such as a transient decrease in motor coordination and balance due to the rapid growth spurt, and tissue stiffness, which can sometimes occur during this period. Level of evidence V; Expert Opinion.

RESUMO O futsal é um esporte que envolve ações motoras de alta intensidade e curta duração, principalmente, saltos verticais e sprints que exigem rápida aplicação de força e velocidade. A avaliação e o treinamento dessas capacidades físicas fazem parte de uma prática rotineira de treinadores, especialmente, das categorias de base, em que há o ingresso de muitas crianças e adolescentes que pretendem seguir uma carreira profissional no futsal. Em relação ao treinamento desse público, a puberdade é um fator que deve ser considerado como um processo biológico natural envolvendo diversas transformações corporais que podem influenciar no desempenho dessas capacidades físicas, principalmente, considerando que as categorias são divididas pela idade cronológica que nem sempre corresponde à idade puberal. O objetivo desse estudo consistiu em realizar uma revisão da literatura em relação às modificações corporais durante a puberdade e como as mesmas podem afetar os aspectos que determinam o bom desempenho em saltos e sprints. Foi verificado que essa fase está associada a alterações hormonais, aumento da massa muscular e aspectos antropométricos, assim como o amadurecimento das funções neuromusculares e refinamento das atividades motoras mais complexas como a locomoção. Juntos, esses fatores podem favorecer a rápida aplicação de força e maior rendimento desses jogadores quanto às atividades motoras. Entretanto, é importante ressaltar que, embora esses fatores aumentem e favoreçam naturalmente o desempenho de força e velocidade dos jogadores, essa é uma fase em que tipos específicos de treinamento focados em aspectos que determinam o bom rendimento são fundamentais para aumentar essas capacidades e diminuir outros aspectos que também podem ocorrer com o desenvolvimento corporal, como por exemplo, a diminuição temporária da coordenação motora e equilíbrio devido ao pico de crescimento e a rigidez tecidual que, algumas vezes, podem ocorrer durante esse período. Nível de evidência V; Opinião de Especialista.

RESUMEN El futsal es un deporte que abarca acciones motoras de alta intensidad y corta duración, principalmente, saltos verticales y sprints, que exigen rápida aplicación de fuerza y velocidad. La evaluación y entrenamiento de estas capacidades físicas forman parte de una práctica rutinaria de entrenadores, especialmente de las categorías de base, en que hay ingreso de muchos niños y adolescentes que pretenden seguir una carrera profesional en el futsal. Con relación al entrenamiento de ese público, la pubertad es un factor que debe ser considerado como un proceso biológico natural involucrando diversas transformaciones corporales que pueden influenciar en el desempeño de esas capacidades físicas, principalmente, considerando que las categorías son divididas por la edad cronológica que no siempre corresponde a la edad puberal. El objetivo de este estudio consistió en realizar una revisión de la literatura con relación a las modificaciones corporales durante la pubertad y cómo pueden las mismas afectar los aspectos que determinan el buen desempeño en saltos y sprints. Se verificó que esta fase está asociada a alteraciones hormonales, aumento de la masa muscular y aspectos antropométricos, así como la madurez de las funciones neuromusculares y refinamiento de las actividades motoras más complejas como la locomoción. Juntos, estos factores pueden favorecer la rápida aplicación de fuerza y mayor rendimiento de estos jugadores cuanto a las actividades motoras. Entretanto, es importante resaltar que, aunque estos factores aumenten y favorezcan naturalmente el desempeño de fuerza y velocidad de los jugadores, esta es una fase en que tipos específicos de entrenamiento enfocados en aspectos que determinan el buen rendimiento son fundamentales para aumentar esas capacidades y disminuir otros aspectos que también pueden ocurrir con el desarrollo corporal, como por ejemplo, la disminución transitoria de la coordinación motora y el equilibrio debido al pico de crecimiento, además de la rigidez tisular que, algunas veces, pueden ocurrir durante ese período. Nivel de evidencia V; Opinión de Especialista.

Effects of dietary sports supplements on metabolite accumulation, vasodilation and cellular swelling in relation to muscle hypertrophy: A focus on "secondary" physiological determinants.

Increased blood flow via vasodilation, metabolite production, and venous pooling contribute to the hyperemia and cellular swelling experienced during resistance training. It has been suggested that these effects play a role in hypertrophic adaptations. Over the past 2 decades, sport supplement products have been marketed to promote exercise hyperemia and intracellular fluid storage, thereby enhancing hypertrophy via acute swelling of myocytes. The three main classes of supplements hypothesized to promote exercise-induced hyperemia include vasodilators, such as nitric oxide precursor supplements; anaerobic energy system ergogenic aids that increase metabolite production, such as ß-alanine and creatine; and organic osmolytes, such as creatine and betaine. Previous studies indicated that these dietary supplements are able to improve muscle performance and thus enhance muscle hypertrophy; however, recent evidences also point to these three classes of supplements affecting "secondary" physiological determinants of muscle mass accretion such as vasodilation, metabolite accumulation, and muscle cellular swelling. Although we recognize that the literature is relatively scarce regarding these topics, a better comprehension and discussion of these determinants can lead to increased knowledge and might guide further research regarding the proposed mechanisms of action of the identified compounds. In this case, increased knowledge may contribute to the development of improved efficacy, new products, or direct new research to specifically investigate those secondary effects. The aim of this review was to bring into focus new perspectives associated with secondary physiological effects induced by supplementation and to determine their relevance.

A prior isometric strength training increases muscle power performance of judo athletes / Exercício preparatório de força isométrico aumenta o desempenho de potência muscular de judocas

ABSTRACT Muscular power, a determinant in judo fights, can be developed by high intensity strength exercises through a mechanism known as post-activation potentiation. Thus, the objective of the present study is to verify the effect of isometric squat exercise on the performance of judo athletes. The sample was made up of eight judo athletes (22.3 ± 3.5 years old, 166.0 ± 6.0 cm; 65.4 ± 7.0 kg). The subjects went through four days of tests, one familiarization session, another as a control situation and two others as experimental sessions. In the experimental sessions, exercises in a Smith squat machine prior to the vertical countermovement jump (CMJ) test and a Special Judo Fitness Test (SJFT). In the control session, only SJFT was performed. Student's t test for paired samples was used to compare performances in the different situations. A significant increase was observed in the number of projections in the SJFT (25.5 ± 2.2 vs. 26.8 ± 2.2 projections) after MVIC and in the height in CMJ (31.0 ± 2.2 vs. 33.3 ± 2.2 cm). The MVIC exercise protocol performed as a preparatory activity increased the performance of judo athletes in judo-specific tests/SJFT and CMJ.

RESUMO A potência muscular, determinante nas lutas de judô, pode ser desenvolvida por exercícios de força de alta intensidade através de um mecanismo conhecido como potenciação pós-ativação. Sendo assim, o objetivo do presente estudo é verificar o efeito do agachamento em isometria no desempenho de judocas. A amostra foi composta por oito judocas (22,3 ± 3,5 anos; 166,0 ± 6,0 cm; 65,4 ± 7,0 kg). Foi realizado quatro dias de testes, uma para sessão de familiarização, uma para a situação controle e duas para sessões experimentais. Nas sessões experimentais foi testado o efeito do exercício de agachamento guiado em contração voluntária isométrica máxima (CVIM) no desempenho do Special Judo Fitness test (SJFT) e do salto vertical com contra movimento (SCM). Na sessão controle foi realizado apenas o SJFT. O teste T Student pareado foi utilizado para comparar o desempenho entre as diferentes situações. Após a execução da CVIM foi observado um aumento significativo no número de arremessos no teste SJFT (25,5±2,2 vs. 26,8±2,2 projeções) e na altura do SCM (31,0 ± 2,2 vs. 33,3±2,2 cm). O protocolo de exercício CVIM realizado como atividade preparatória aumentou o desempenho de atletas de judô em teste específicos do Judô / SJFT e de SCM.

Dietary proteins and amino acids in the control of the muscle mass during immobilization and aging: role of the MPS response.

Dietary proteins/essential amino acids (EAAs) are nutrients with anabolic properties that may increase muscle mass or attenuate muscle loss during immobilization and aging via the stimulation of muscle protein synthesis (MPS). An EAA's anabolic threshold, capable to maximize the stimulation of MPS has been hypothesized, but during certain conditions associated with muscle loss, this anabolic threshold seems to increase which reduces the efficacy of dietary EAAs to stimulate MPS. Preliminary studies have demonstrated that acute ingestion of dietary proteins/EAA (with a sufficient amount of leucine) was capable to restore the postprandial MPS during bed rest, immobilization or aging; however, whether these improvements translate into chronic increases (or attenuates loss) of muscle mass is equivocal. For example, although free leucine supplementation acutely increases MPS and muscle mass in some chronic studies, other studies have reported no increases in muscle mass following chronic leucine supplementation. In contrast, chronically increasing leucine intake via the consumption of an overall increase in dietary protein appears to be the most effective dietary intervention toward increasing or attenuating lean mass during aging; however, more research investigating the optimal dose and timing of protein ingestion is necessary. Several studies have demonstrated that decreases in postprandial MPS as a result of increased circulating oxidative and inflammatory are more responsible than muscle protein breakdown for the decreases in muscle mass during disuse and health aging. Therefore, nutritional interventions that reduce oxidation or inflammation in conjunction with higher protein intakes that overcome the anabolic resistance may enhance the MPS response to feeding and either increase muscle mass or attenuate loss. In preliminary studies, antioxidant vitamins and amino acids with antioxidant or anti-inflammatory properties show potential to restore the anabolic response associated with protein ingestion. More research, however, is required to investigate if these nutrients translate to increases in MPS and, ultimately, increased lean mass in aging humans. The purpose of the present review is to discuss the role of protein/EAA intake to enhance postprandial MPS during conditions associated with muscle loss, and bring new perspectives and challenges associated nutritional interventions aimed to optimize the anabolic effects of dietary protein/EAAs ingestion.

Comparison of different ways of expressing creatine kinase concentration of soccer players during a competitive season

The aim of this study was to analyze the responses of creatine kinase [CK] expressed in different forms to the training load of professional soccer players during a competitive season. Twelve players (age, 24 ± 4 years) participated in the study. [CK] was analyzed before the pre-season (Pre), after the pre-season (Post), and in the competitive mesocycles (M1, M2, and M3). Results showed [CK] in the Pre, Post, M1, M2, and M3 phases in absolute values (181.3 ± 58.7, 416.4 ± 155.7, 526.4 ± 268.0, 403.8 ± 137.0, and 442.5 ± 212.3 U/L, respectively), relative values (16.3 ± 4.6, 39.5 ± 19.1, 47.8 ± 20.1, 37.5 ± 14.2, 40.1 ± 17.4 %CKmáx, respectively), and values relative to the variation delta (19.9 ± 3.6, 48.1 ± 26.5, 57.0 ± 23.2, 45.1 ± 17.7, and 48.3 ± 22.0 %ΔCKmáx, respectively). [CK] was lower only during the Pre phase compared to the other phases (p < 0.05). [CK] was expressed as %CKmáx or %ΔCKmáx may be more specific to monitor training. In addition, the individualization of this biomarker optimizes the athletes' performance as muscle injuries can be prevented

Analysis and comparison of intensity in specific soccer training sessions

This study compared the exercise intensity of four specific soccer training sessions (friendly and training match, tactical and technical workouts). Ten professional soccer players (24.2 ± 3.7 years, 177.9 ± 7.3 cm, 63.2 ± 4.6 mLO2•kg-1•min-l) were recruited. A treadmill progressive interval test was performed to determine the players' VO2max, maximal heart rate (HRmax), HR-VO2 curve, and the heart rate corresponding to blood lactate concentrations of 2 and 4 mmol/L. The heart rate during the training sessions was used to estimate the exercise intensity and to classify them into intensity zones (low-intensity: <2 mmol/L; moderate-intensity: between 2 and 4 mmol/L; high-intensity: >4 mmol/L). Exercise intensities were different among training sessions (friendly match: 86.0 ± 5.1% HRmax; training match: 81.2 ± 4.1% HRmax; tactical workout: 70.4 ± 5.3% HRmax; technical workout: 62.1 ± 3.6% HRmax). The friendly match presented the highest percentage of time performed in the high-intensity zone.

Este estudo comparou a intensidade de quatro treinamentos específicos de futebol (jogo treino, amistoso, treinos técnicos e táticos). Dez jogadores de futebol profissional foram recrutados (24,2 ± 3,7 anos, 177,9 ± 7,3 cm, 63,2 ± 4,6 mLO2•kg-1•min-l). Um teste progressivo intervalado em esteira foi realizado para determinar o VO2max, frequência cardíaca máxima (FCmax), curva FC-VO2, e frequência cardíaca correspondente às concentrações de lactato de 2 e 4 mmol/L. A frequência cardíaca dos treinos foi usada para estimar a intensidade do exercício e classificá-los em zonas de intensidade (baixa, <2 mmol/L; moderada: entre 2 e 4 mmol/L; alta: >4 mmol/L). As intensidades das sessões de treinamento foram diferentes (jogo amistoso: 86,0 ± 5,1% FCmax; jogo treino: 81,2 ± 4,1 % FCmax; treino tático: 70,4 ± 5,3% FCmax; treino técnico: 62,1 ± 3,6% FCmax). O jogo amistoso apresentou porcentagem mais alta de tempo realizado na zona de intensidade alta.

Este estudio comparó la intensidad de cuatro entrenamientos específicos de futbol (juego de entrenamiento, amistoso, técnico y táctico). Diez jugadores de futbol profesional fueron reclutados (24,2 ± 3,7 años, 177,9 ± 7,3 cm, 63,2 ± 4,6 mLO2•kg-1•min-l). Un examen con intervalos progresivos en la caminadora fue realizado para determinar: VO2max, FCmax, curva FC-VO2 y frecuencia cardiaca correspondiente a las concentraciones de lactato de 2 y 4 mml/L. La frecuencia cardiaca de los entrenamientos fue usada para estimar la intensidad del ejercicio y clasificar zonas de intensidad (baja <2 mmol/L; moderada >2 y <4 mmol/L; alta >4 mmol/L). Las intensidades de las sesiones de entrenamiento fueron diferentes (juego amistoso: 86,0 ± 5,1% FCmax; entrenamiento 81,2 ± 4,1 % FCmax; entrenamiento táctico 70,4 ± 5,3% FCmax; entrenamiento técnico 62,1 ± 3,6% FCmax). El juego amistoso presentó porcentaje más alto de tiempo realizado en la zona de intensidad alta.

Limiar anaeróbico de 4 mM é capaz de estimar a máxima fase estável de lactato de jogadores de futebol em testes de campo / Anaerobic threshold of 4.0mM is able to estimate the maximal lactate steady state of soccer players on the field tests

Diante à importância da capacidade aeróbia para o desempenho de jogadores de futebol, o Limiar Anaeróbio tem sido um parâmetro comumente utilizado para a avaliação desses atletas. Todavia, faltam informações a respeito da validade dos protocolos de campo adotados no meio futebolístico. Portanto, o objetivo do presente estudo foi comparar os valores de velocidade de corrida (VC) e frequência cardíaca (FC) associados à máxima fase estável de lactato (MFEL) e limiar anaeróbico de 4,0mM (OBLA), e verificar se uma concentração fixa de lactato de 4 mM pode ser utilizada para estimar a MFEL em jogadores de futebol em testes de campo. Para tanto 22 jogadores de futebol da categoria sub 20 anos (18,1 ± 0,2 anos) foram avaliados. O OBLA foi considerado como a VC correspondente a lactatemia de 4,0mM e a MFEL foi determinada por meio de exercícios submáximos de intensidade constante com duração de 30 minutos. Os resultados não demonstraram diferenças significativas entre VC e FC identificadas pela MFEL e OBLA e apresentaram correlação significativa entre VC identificada pela MFEL e OBLA (r=0,56; p<0,01). Conclui-se que a concentração fixa de lactato 4mM (OBLA) pode ser utilizada para estimar a VC associada à MFEL em jogadores de futebol em testes de campo. A FC deve ver utilizada com cautela quanto aplicada isoladamente para controle de intensidade.(AU)

Given the importance of aerobic capacity for the performance of soccer players, the Anaerobic Threshold has been a commonly parameter used to assess these athletes. However, there is missing information about the validity of field protocols adopted in the soccer environment. Therefore, the aim of this study was to compare the values of running speed (RS) and heart rate (HR) associated with the maximal lactate steady state (MLSS) and anaerobic threshold of 4.0mM (OBLA), and identify whether a fixed lactate concentration of 4 mM can be used to estimate the MLSS in soccer players in field tests. Twenty two soccer players of under 20 (18.1 ± 0.2 years) were evaluated. OBLA was taken as the RS corresponding to blood lactate concentration of 4.0 mM and MLSS was determined by sub maximal constant intensity exercise with a duration of 30 minutes. The results showed no significant differences between RS and HR identified by the MLSS and OBLA and showed significant correlation between the RS identified by MLSS and OBLA (r=0.56, p< 0.01). It is concluded that fixed concentration of 4 mM lactate (OBLA) can be used to estimate the RS associated with MLSS in soccer players in field tests. HR should be used with caution when applied separately for intensity control.(AU)

Maximal power output estimates the MLSS before and after aerobic training / Potência máxima estima a MFEL antes e após o treinamento aeróbio / Potencia máxima estima el MLSS antes y después del entrenamiento aerobio

The purpose of this study is to present an equation to predict the maximal lactate steady state (MLSS) through a VO2peak incremental protocol. Twenty-six physically active men were divided in two groups (G1 and G2). They performed one maximal incremental test to determine their VO2peak and maximal power output (Wpeak), and also several constant intensity tests to determine MLSS intensity (MLSSw) on a cycle ergometer. Group G2 underwent six weeks of aerobic training at MLSSw. A regression equation was created using G1 subjects Wpeak and MLSSw to estimate the MLSS intensity (MLSSweq) before and after training for G2 (MLSSweq = 0.866 x Wpeak-41.734). The mean values were not different (150±27W vs 148±27W, before training / 171±26W vs 177±24W, after training) and significant correlations were found between the measured and the estimated MLSSw before (r²=0.49) and after training (r²=0.62) in G2. The proposed equation was effective to estimate the MLSS intensity before and after aerobic training...

Este estudo propõe uma equação para predição da máxima fase estável de lactato (MFEL) através de um teste para medida do VO2pico. Vinte e seis homens fisicamente ativos foram divididos em dois grupos (G1 e G2). Eles realizaram um teste máximo para medida do VO2pico e potência máxima (Ppico) e testes submáximos para determinar a intensidade da MFEL (MFELw) em cicloergômetro. O grupo G2 treinou por seis semanas na MFELw. Uma equação de regressão linear foi desenvolvida utilizando os resultados do G1 (Ppico e MFELw) para estimativa da MFEL (MFELweq) antes e após o treinamento no G2 (MFELweq=0,866 x Ppico-41,734). Os valores médios não foram diferentes (150±27W vs 148±27W, pré-treino / 171±26W vs 177±24W, pós-treino) e encontrou-se uma correlação significativa entre a MFELw medida e estimada antes (r²=0,49) e após o treinamento (r²=0,62) no grupo G2. A equação proposta foi efetiva para estimar a MFEL antes e após o treinamento...

Este estudio propone una ecuación para la predicción del máximo estado estable de lactato (MLSS) a través de un test para medir VO2pico. Veintiséis hombres físicamente activos se dividieron en dos grupos (G1 y G2). Ellos realizaron un test máximo para medir el VO2pico y potencia máxima (Ppico) y testes submáximas para determinar la intensidad de la MLSS (MLSSw) en cicloergómetro. El grupo G2 entrenó por seis semanas en la MLSSw. Una ecuación de regresión lineal fue desarrollada utilizando los resultados del G1 (Ppico y MLSSw) para estimar la MLSS (MLSSweq) antes y después del entrenamiento en el G2 (MFELweq=0,866 x Ppico-41,734). Los valores medios no fueron distintos (150±27W vs 148±27W, pre-entrenamiento / 171±26W vs 177±24W, después del entrenamiento) y se encontró una correlación significativa entre la MFELw medida y estimada antes (r²=0,49) y después del entrenamiento (r²=0,62) en el G2. La ecuación propuesta fue eficaz para estimar la MLSS antes y después del entrenamiento...