The Effects of a Supramaximal Intermittent Training Program on Aerobic and Anaerobic Running Measures in Junior Male Soccer Players.

This study investigated the effectiveness of supplementing regular preseason soccer training with a supramaximal intermittent shuttle-run training (ISRT) model prescribed from Carminatti's Test peak speed (PST-CAR) in aerobic performance-related indices and sprinting speed in male junior soccer players. Twenty-three national-level soccer players (mean ± SD; age 18.07 ± 0.9 y, body height 1.76 ± 0.65 m, body mass 71.9 ± 8.7 kg) were assigned to either an experimental group (EG; n = 13) performing ISRT + soccer training or a control group (CG; n = 10) that followed regular preseason soccer training alone. The following tests were applied before and after the eight-week training intervention: (i) incremental treadmill tests (VO2max and lactate minimum speed - LMS); (ii) linear 30-m sprint test and Carminatti's Test (PST-CAR). Results indicated larger gains for the EG in LMS (Δ = 9.53% vs. 2.82%) and PST-CAR (Δ = 5.50% vs. 2.10%) than in the CG. Furthermore, changes in VO2max produced higher effect size (d) values for the EG (Δ = 6.67%; d = 0.59) than the CG (Δ = 1.88%; d = 0.18). Both groups improved (p = 0.002) their flying 20-m sprint speed (EG: Δ = 1.01%; CG: Δ = 1.56%). However, small decreases were observed for 10-m sprint speed in the CG (Δ = -2.19%; d = -0.44), while only trivial changes were noticed for the EG (Δ = -0.50%; d = -0.16). Our data support that additional supramaximal ISRT is an effective training stimulus to enhance aerobic performance-related indices and promote small improvements in maximal running speed without impairing the soccer players' acceleration capacity. This study also shows that PST-CAR can be useful for individualizing running intensity in supramaximal ISRT modes.

Match-Play Running Performance in Professional Male Soccer Players: The Role of Anaerobic Speed Reserve.

Purpose: This study aimed to compare match-play running performance between players with a high (HASR) and low (LASR) anaerobic speed reserve (ASR) profile in professional soccer players. Method: Thirty-six male players from the same club (age: 23.3 ± 5.4 years) took part in this study. Match data were collected from 43 home matches of the first and second division of the Brazilian National Championship over two consecutive seasons. Players had their maximal sprinting (MSS) and aerobic speeds (MAS) determined during field test-based assessments. ASR was defined as MSS minus MAS. Total distance (TD), sprinting distance, number of accelerations and decelerations, absolute peak (PMS(abs)) and mean match sprint speed (MMSS(abs)) and its relative values expressed as a percentage of MSS (PMS(rel) and MMSS(rel)), distance covered > 100% MAS(abs) and > 50% MSS(abs) were compared between the groups and halves. Results: HASR presented greater sprint demand (d > 0.80), PMS(abs) (d = 1.57), and MMSS(abs) (d = 0.99) than the LASR group. The opposite was observed for PMS(rel) and MMSS(rel). The TD and amount of high-intensity accelerations and decelerations were moderately (0.77MAS(abs) and > 50% MSS(abs) decreased between halves (d = 0.72 and 0.77), while the HASR did not (d < 0.10). Conclusion: Our findings indicated that players with larger ASR had greater sprint demand, with a lower relative running intensity, and covered longer distances above MAS. The amplitude of ASR also affected the player's running ability between halves.

Association between internal training load and muscle injuries in Brazilian professional soccer players.

The training load is associated with injury risk in a variety of sports. This study aimed to evaluate the association between the internal training load and injury risk in Brazilian professional soccer players. The data were collected from 32 soccer players across two full seasons (2017 and 2018). The rating of perceived exertion (RPE) for every training/match session was used as an internal load variable. The cumulative training load from 3 and 4 weeks (C3 and C4) and the acute:chronic workload ratio (ACWR) were calculated. A generalized estimating equation analysis was applied to examine associations of non-contact muscle injuries with C3, C4 and ACWR. A total of 33 injuries were recorded across the two full seasons. A significant association was found between cumulative training load for three (C3, p = 0.003) and four weeks (C4, p = 0.023) and the occurrence of injuries. Players in the "high load" group presented greater injury risk in relation to the "moderate load" group (C4: OR = 4.5; IC 95% 1.5-13.3; C3: OR = 3.7; IC 95% 1.7-8.1). There was no association between ACWR and injury occurrence. The athletes exposed to a high cumulative load in a period of 3 to 4 weeks presented higher injury risk in comparison to those who had moderate cumulative training loads. Besides that, there was no association between ACWR and injury occurrence.

A Pilot Study on the Prediction of Non-Contact Muscle Injuries Based on ACTN3 R577X and ACE I/D Polymorphisms in Professional Soccer Athletes.

Muscle injuries are among the main reasons for medical leavings of soccer athletes, being a major concern within professional teams and their prevention associated with sport success. Several factors are associated with a greater predisposition to injury, and genetic background is increasingly being investigated. The aim of this study was to analyze whether ACTN3 R577X and ACE I/D polymorphisms are predictors of the incidence and severity of muscle injury in professional soccer athletes from Brazil, individually and in association. Eighty-three professional athletes from the first and second divisions of the Brazilian Championship were evaluated regarding the polymorphisms through blood samples. Nighty-nine muscle injuries were identified during the seasons of 2018, 2019 and 2020 and categorized according to severity. ACTN3 XX individuals had a higher frequency of severe injuries compared to the RX and RR genotypes (p = 0.001), and in the dominant model (compared to RX+RR), with p < 0.001. The trend p-value test showed an increased number of injuries/season following the order XX > RX > RR (p = 0.045). Those with the ACE II genotype had almost 2 fold the number of injuries per season compared to those with the ID+DD genotypes (p = 0.03). Logistic regression showed that the polymorphisms are predictors of the development of severe injury (ACTN3 R577X model with p = 0.004, R2: 0.259; ACE I/D model with p = 0.045, R2: 0.163), where ACTN3 XX individuals were more likely to suffer from severe injury (OR: 5.141, 95% CI: 1.472-17.961, p = 0.010). The combination of the ACTN3 577X allele and the ACE II genotype showed an increased number of injuries per season, enhanced by 100% (1.682 injuries/season versus 0.868 injuries/season, p = 0.016). Our findings suggest that both polymorphisms ACTN3 R577X and ACE I/D (and their interaction) are associated with the susceptibility and severity of non-contact muscle injury in soccer players.

Sintomas de distúrbios osteomusculares em profissionais de educação física, atuantes em academias de Florianópolis-SC / Symptoms of musculoskeletal disorders in physical education teachers working in academies of Florianópolis-SC / Síntomas de disturbios musculares entre os profesionales de educación física actuantes en centros de acondicionamiento de Florianópolis-SC

O objetivo do estudo foi verificar os sintomas de distúrbios osteomusculares - SDO em professores de academias e sua associação com jornada de trabalho, sexo e função exercida. O estudo foi do tipo transversal e contou com a participação de 54 professores. Os SDO foram verificados através do Questionário Nórdico de Sintomas Osteomusculares. A média de idade foi de 31,2 (± 6,9) anos. Verificou-se que 41 (75,9 por cento) professores relataram SDO em pelo menos uma região anatômica nos últimos 12 meses e 25 (46,3 por cento) nos últimos sete dias. Trabalhar mais de oito horas/dia e exercer duas ou mais funções apresentaram relação positiva com SDO na "parte inferior das costas". Apesar deste profissional apregoar a saúde e o bem-estar físico, a prevalência de SDO foi alta e semelhante com a de outras profissões.

The aim of this study was to assess the symptoms of musculoskeletal disorders (SMD) on gym teachers, and its association with working hours, gender, and job function. The study was cross-sectional and relied on 54 gym teachers of both sexes. We used a questionnaire containing demographic and occupational data. The SMD was verified using the Nordic Musculoskeletal Questionnaire. The questionnaire was self-applied in the workplace. The mean age of subjects was 31.2 (± 6.9) years. It was found that 41 teachers (75.9 percent) reported SMD in at least one anatomical region in the past 12 months. The anatomic region most often cited was the lumbar (24 patients, 44.4 percent). One in every three employees took sick leave from work, and 22 subjects (40.7 percent) consulted a health care professional in the past 12 months, due to the SMD. Working more than 8 hours a day, and exercising two or more functions were closely related to SMD in the lumbar region. The results showed that musculoskeletal disorders were prevalent among physical education teachers working in academies. The severity of the SMD could be gauged by the frequency of sick leave from work.

El objetivo del presente estudio fue verificar los síntomas de disturbios musculares (SDM) en profesores de centros de acondicionamiento físico y su asociación con jornada de trabajo, sexo y función ejercida. El estudio fue del tipo transversal y contó con la participación de 54 profesores de centros de acondicionamiento físico, de ambos sexos. Se utilizó un cuestionario conteniendo datos demográficos y ocupacionales. Los SDM fueron verificados, utilizándose el Cuestionario Nórdico de Síntomas Musculares. El cuestionario fue auto aplicado, en el lugar de trabajo. La media de edad de los individuos fue 31,2 (± 6,9) años. Se verificó que 41 profesores (75,9 por ciento) relataron SDM en por lo menos una región anatómica, en los últimos 12 meses. La región lumbosacra fue la región anatómica más citada (24 individuos, 44,4 por ciento). Uno en cada tres profesionales relató necesidad de alejamiento del trabajo y 22 individuos (40,7 por ciento) consultaron algún profesional del área de salud en los últimos 12 meses, debido a los SDM. Trabajar más de 8 horas/día y ejercer dos o más funciones presentaron relación positiva con SDM en la región lumbosacra. Los resultados mostraron que los SDM fueron prevalentes entre los profesionales de educación física actuantes en centros de acondicionamiento físico. La gravedad de los SDM puede ser observada por la frecuencia de necesidad de alejamiento del trabajo.