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This study aimed to evaluate the effects of cumulative school soccer matches separated by 24-h or 48-h intervals on recovery status of U-19 players. Thirty-four school athletes (17.6 ± 1.1 years) who played an U-19 school soccer competition (composed of one group with four teams and another group with three teams, followed by semifinals and final) were examined before three matches, which lasted 70 min. Seventeen athletes had 24-h of rest interval between each match (GGG group), while 18 athletes had an interval of 48-h between the second and third matches (GG48hG group). Total Quality Recovery, countermovement jump, 10-m sprint, and maximum lumbar isometric strength were measured. The internal load of each match was calculated by the product of the session Rating of Perceived Exertion and match time. There was a 22% reduction in Total Quality Recovery (p< 0.001) and 12% in 10-m sprint performance (p< 0.001) before the third match in the GGG group, while the GG48hG group did not show changes for the same variables (p> 0.05). The countermovement jump decreased before the second match in both groups (GGG= 12% and GG48hG= 10%; p< 0.001), with no difference between groups (p> 0.05). In addition, both groups did not show changes in the isometric strength and in the internal load match over the games (p> 0.05). Despite not providing a complete muscle recovery, 48-h interval between the second and third matches seems to have minimized the effect of consecutive matches in muscle performance reduction. Este estudo teve como objetivo avaliar os efeitos de partidas consecutivas de futebol escolar com intervalos de 24 e 48 horas no estado de recuperação física de jogadores Sub-19. Foram avaliados 35 homens (17,6±1,1 anos) atletas escolares sub-19. Durante a competição, foram realizados três jogos de 70-min de duração. Dezessete atletas tiveram intervalo de 24h entre cada jogo (grupo GGG). Dezoito atletas tiveram intervalo de 48 h entre o 2º e o 3º jogo (grupo GG48hG). Antes de cada jogo foram medidas a Qualidade Total de Recuperação, altura do salto com contra movimento, velocidade no sprint de 10-m, e força máxima isométrica lombar máxima. A carga interna do jogo foi calculada pelo produto da percepção subjetiva do esforço da sessão e tempo de cada jogo. Houve uma redução de 22% na qualidade total de recuperação (p 0,05). O salto com contra movimento diminuiu antes da segunda partida em ambos os grupos (GGG = 12% e GG48hG = 10%; p 0,05). Em adição, ambos os grupos não apresentaram alterações na força isométrica e na carga interna ao longo dos jogos (p> 0,05). Apesar de não proporcionar uma completa recuperação muscular, 48 h de intervalo entre o segundo e o terceiro jogo parece ter minimizado o efeito de jogos consecutivos na redução do desempenho.

espanolAntecedentes: el objetivo del presente estudio fue comparar la prevalencia del sindrome metabolico en ninos brasilenos de 6 a 10 anos de edad, usando tres diferentes criterios internacionales. Metodos: se midieron la presion arterial sistolica y diastolica, el colesterol de alta y baja densidad, los trigliceridos, la glucemia en ayunas y la insulinemia en 290 escolares, y se analizo la presencia del sindrome metabolico de acuerdo con los criterios de Cook, Boney y Ferreira. Resultados: la prevalencia del sindrome metabolico encontradas fueron del 2,27 % (criterios de Boney y Ferreira) y 7,58 % (criterios de Cook) para las ninas, y del 3,8 % (criterios de Boney y Ferreira) y 5,06 % (criterios de Cook) para los ninos. La concordancia por pares fue del 57,5 % (Kappa = 0,57) entre los criterios de Boney y Cook, y del 65,2 % (Kappa = 0,65) entre los criterios de Cook y Ferreira. La mayor concordancia encontrada fue del 77 % (Kappa = 0,77) entre los criterios de Boney y Ferreira, demostrando una concordancia sustancial. Conclusiones: la prevalencia de acuerdo con los criterios de Boney y Ferreira fue inferior a la encontrada con los criterios de Cook. Por lo tanto, sugerimos el uso de los criterios de Cook en la practica clinica para el diagnostico del sindrome metabolico, ya que utilizando este criterio se obtiene un rango diagnostico mas amplio, reduciendose asi el riesgo del infradiagnostico. EnglishBackground: the aim of the present study was to compare the prevalence of metabolic syndrome in Brazilian children aged 6-10 years using three different international criteria. Methods: systolic and diastolic blood pressure (SBP and DBP), high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, triglycerides, fasting glucose, and insulin levels were measured in 290 schoolchildren, and the presence of metabolic syndrome was analyzed according to the criteria established by Cook, Boney, and Ferreira. Results: the prevalence of metabolic syndrome was 2.27 % (Boney and Ferreira criteria) and 7.58 % (Cook criteria) for girls, and 3.8 % (Boney and Ferreira criteria) and 5.06 % (Cook criteria) for boys. Agreement in pairs showed a concordance of 57.5 % (Kappa = 0.57) between Boney and Cook criteria, and 65.2 % (Kappa = 0.65) between Cook and Ferreira. The greatest concordance found was 77 % (Kappa = 0.77) between Boney and Ferreira criteria, demonstrating a substantial agreement. Conclusion: prevalence according to Boney and Ferreira criteria was lower than according to Cook criteria. Therefore, we suggest the use of Cook criteria in clinical practice for the diagnosis of metabolic syndrome, since this criterion provided a wider diagnostic range, thereby reducing the risk of underdiagnosis.

The study investigates whether tensiomyography (TMG) is sensitive to differentiate between strength and endurance athletes, and to monitor fatigue after either one week of intensive strength (ST) or endurance (END) training. Fourteen strength (24.1±2.0years) and eleven endurance athletes (25.5±4.8years) performed an intensive training period of 6days of ST or END, respectively. ST and END groups completed specific performance tests as well as TMG measurements of maximal radial deformation of the muscle belly (Dm), deformation time between 10% and 90% Dm (Tc), rate of deformation development until 10% Dm (V10) and 90% Dm (V90) before (baseline), after training period (post1), and after 72h of recovery (post2). Specific performance of both groups decreased from baseline to post1 (P0.05) and returned to baseline values at post2 (P0.05). The ST group showed higher countermovement jump (P0.05) and shorter Tc (P0.05) at baseline. After training, Dm, V10, and V90 were reduced in the ST (P0.05) while TMG changes were less pronounced in the END. TMG could be a useful tool to differentiate between strength and endurance athletes, and to monitor fatigue and recovery especially in strength training.

This aimed to analyze neuromuscular, physiological and perceptual responses to a single bout of 5 different dynamic squat exercise protocols. In a randomized and counterbalanced order, 15 male resistance-trained athletes (mean ± SD; age: 23.1 ± 1.9 years, body mass: 77.4 ± 8.0 kg) completed traditional multiple sets (MS: 4 × 6, 85% 1 repetition maximum [RM]), drop sets (DS: 1 × 6, 85% 1RM + 3 drop sets), eccentric overload (EO: 4 × 6, 70% 1RM concentric, 100% 1RM eccentric), flywheel YoYo squat (FW: 4 × 6, all-out), and a plyometric jump protocol (PJ: 4 × 15, all-out). Blood lactate (La), ratings of perceived exertion (RPE), counter movement jump height (CMJ), multiple rebound jump (MRJ) performance, maximal voluntary isometric contraction force, serum creatine kinase (CK) and delayed onset muscle soreness were measured. Immediately post exercise, La was significantly (p < 0.001) higher in FW (mean ± 95% confidence limit; 12.2 ± 0.9 mmol·L) and lower in PJ (3.0 ± 0.8 mmol·L) compared with MS (7.7 ± 1.5 mmol·L), DS (8.5 ± 0.6 mmol·L), and EO (8.2 ± 1.6 mmol·L), accompanied by similar RPE responses. Neuromuscular performance (CMJ, MRJ) significantly remained decreased (p < 0.001) from 0.5 to 48 hours post exercise in all protocols. There was a significant time × protocol interaction (p ≤ 0.05) in MRJ with a significant lower performance in DS, EO, and FW compared with PJ (0.5 hours post exercise), and in EO compared with all other protocols (24 hours post exercise). A significant main time effect with peak values 24 hours post exercise was observed in CK serum concentrations (p < 0.001), but there was no time × protocol interaction. In conclusion, (a) metabolic and perceptual demands were higher in FW and EO compared with MS, DS and PJ, (b) neuromuscular fatigue was consistent up to 48 hours post exercise in all protocols, and

The purpose of the study was to analyze tensiomyography (TMG) sensitivity to changes in muscle force and neuromuscular function of the muscle rectus femoris (RF) using TMG muscle properties after 5 different lower-limb strength training protocols (multiple sets; DS = drop sets; eccentric overload; FW = flywheel; PL = plyometrics). After baseline measurements, 14 male strength trained athletes completed 1 squat training protocol per week over a 5-week period in a randomized controlled order. Maximal voluntary isometric contraction (MVIC), TMG measurements of maximal radial displacement of the muscle belly (Dm), contraction time between 10 and 90% of Dm (Tc), and mean muscle contraction velocities from the beginning until 10% (V10) and 90% of Dm (V90) were analyzed up to 0.5 (post-train), 24 (post-24), and 48 hours (post-48) after the training interventions. Significant analysis of variance main effects for measurement points were found for all TMG contractile properties and MVIC (p < 0.01). Dm and V10 post-train values were significantly lower after protocols DS and FW compared with protocol PL (p = 0.032 and 0.012, respectively). Dm, V10, and V90 decrements correlated significantly to the decreases in MVIC (r = 0.64-0.67, p ≤ 0.05). Some TMG muscle properties are sensitive to changes in muscle force, and different lower-limb strength training protocols lead to changes in neuromuscular function of RF. In addition, those protocols involving high and eccentric load and a high total time under tension may induce higher changes in TMG muscle properties.

The current study involved the completion of two distinct experiments. Experiment 1 analyzed the inter-day reliability of tensiomyography (TMG) muscle mechanical properties based on the amplitude of the muscle belly radial deformation, the time it takes to occur, and its velocity under maximal and submaximal stimuli, in the muscles rectus femoris, biceps femoris, and gastrocnemius lateralis, from 20 male sport students. Experiment 2 investigated whether changes in maximal voluntary isometric contraction (MVIC) could be predicted based on changes in TMG properties following 24 h after different squat training protocols (MS = multiple sets; DS = drop sets; EO = eccentric overload; FW = flywheel; PL = plyometrics) executed by 14 male strength trained athletes. Maximal electrical stimulation exhibited higher level of reliability. In most of the cases, TMG properties Tc, Td, Dm, V10, and V90 showed ICC scores >.8 and CV

Raeder, C, Wiewelhove, T, Simola, RADP, Kellmann, M, Meyer, T, Pfeiffer, M, and Ferrauti, A. Assessment of fatigue and recovery in male and female athletes after 6 days of intensified strength training. J Strength Cond Res 30(12): 3412-3427, 2016-This study aimed to analyze changes of neuromuscular, physiological, and perceptual markers for routine assessment of fatigue and recovery in high-resistance strength training. Fourteen male and 9 female athletes participated in a 6-day intensified strength training microcycle (STM) designed to purposefully overreach. Maximal dynamic strength (estimated 1 repetition maximum [1RMest]; criterion measure of fatigue and recovery); maximal voluntary isometric strength (MVIC); countermovement jump (CMJ) height; multiple rebound jump (MRJ) height; jump efficiency (reactive strength index, RSI); muscle contractile properties using tensiomyography including muscle displacement (Dm), delay time (Td), contraction time (Tc), and contraction velocity (V90); serum concentration of creatine kinase (CK); perceived muscle soreness (delayed-onset muscle soreness, DOMS) and perceived recovery (physical performance capability, PPC); and stress (MS) were measured before and after the STM and after 3 days of recovery. After completing the STM, there were significant (p ≤ 0.05) performance decreases in 1RMest (%[INCREMENT] ± 90% confidence limits, ES = effect size; -7.5 ± 3.5, ES = -0.21), MVIC (-8.2 ± 4.9, ES = -0.24), CMJ (-6.4 ± 2.1, ES = -0.34), MRJ (-10.5 ± 3.3, ES = -0.66), and RSI (-11.2 ± 3.8, ES = -0.73), as well as significantly reduced muscle contractile properties (Dm, -14.5 ± 5.3, ES = -0.60; V90, -15.5 ± 4.9, ES = -0.62). After days of recovery, a significant return to baseline values could be observed in 1RMest (4.3 ± 2.8, ES = 0.12), CMJ (5.2 ± 2.2, ES = 0.28), and MRJ (4.9 ± 3.8, ES = 0.32), whereas RSI (-7.9 ± 4.5, ES = -0.50), Dm (-14.7 ± 4.8, ES = -0.61), and V90 (-15.3 ± 4.7, ES = -0.66) remained significantly reduced. The STM also induced significant changes of large practical relevance in CK, DOMS, PPC, and MS before to after training and after the recovery period. The markers Td and Tc remained unaffected throughout the STM. Moreover, the accuracy of selected markers for assessment of fatigue and recovery in relation to 1RMest derived from a contingency table was inadequate. Correlational analyses also revealed no significant relationships between changes in 1RMest and all analyzed markers. In conclusion, mean changes of performance markers and CK, DOMS, PPC, and MS may be attributed to STM-induced fatigue and subsequent recovery. However, given the insufficient accuracy of markers for differentiation between fatigue and recovery, their potential applicability needs to be confirmed at the individual level.

Tensiomyography (TMG) reliability and external validity using maximal voluntary isometric contraction (MVIC) following different strength training protocols (STP) were analysed. Twenty healthy male were tested two times over one week and TMG reliability was analysed in the muscles Rectus Femoris (RF), Biceps Femoris (BF), and Gastrocnemius Lateralis (GL), after an individual maximal and submaximal electrical stimulation. Moreover, TMG external validity was assessed through Pearson correlation between changes in TMG muscle mechanical properties in RF and changes in MVIC in squat exercise after five different lower-limb STPs. Maximal electrical stimulation showed the highest ICC scores for TMG muscle properties reliability in all muscles investigated. Significant Pearson correlation coefficients were found between changes in TMG mechanical properties and changes in MVIC after STPs characterized by high intensity, time under tension and eccentric overload. TMG is a valid and reliable method to assess muscle mechanical properties especially under maximal condition. ISBN: 978-989-758-159-5