Muscle Pain Code: a novel tool for screening the risk of time-loss muscle injury in professional male football players.

OBJECTIVE: To investigate the association of a novel post-match muscle pain map, named Muscle Pain Code (MPC), with the risk of subsequent time-loss muscle injury in a cohort of professional football (soccer) players. METHODS: The MPC classifies pain in four codes: code 0, 'no pain;' code 1, 'generalized muscle pain;' code 2, 'diffused site muscle pain;' and code 3, 'specific site muscle pain.' Over four consecutive seasons, MPC was collected on the second post-match day and players were followed for occurrence of time-loss muscle injury over the next five days. Players exposed to at least 45 minutes in two consecutive matches within seven days were included as cases for analysis. RESULTS: Eighty players participated in the study. Of 1,656 cases analyzed, 229 resulted in time-loss muscle injuries. Only 2% of cases with codes 0 and 1 resulted in time-loss muscle injuries. Conversely, 63% and 78% of codes 2 and 3 were followed by time-loss muscle injuries, respectively. Compared with the reference scenario (i.e. code 0 on MPC), the risk of subsequent time-loss muscle injury was significantly higher when players recorded code 2 (odds ratio, 4.29; 95%CI, 3.62 to 4.96) or code 3 (odds ratio, 5.01; 95%CI, 4.05 to 5.98) on MPC, but not when they recorded code 1 (odds ratio = -0.27; 95%CI, 1.05 to 0.56). CONCLUSIONS: Players experiencing well-outlined pain area on the second post-match day were more likely to incur a time-loss muscle injury in the subsequent days compared to those experiencing spreading pain or no pain.

Creatine kinase concentration on the second post-match day is not associated with risk of subsequent muscle injury in professional football players: a four-season cohort study.

OBJECTIVE: The objective of this study was to examine the relationship between creatine kinase (CK) concentration following official matches and the risk of subsequent muscle injury in professional male football (soccer) players. METHODS: Blood samples were collected on the second post-match day for CK analysis over four consecutive seasons in a professional football club. Players were then followed for five days to observe any occurrence of indirect muscle injury (structural or functional in nature). Players exposed to at least 45 minutes in two consecutive matches within seven days were considered valid cases for analysis. RESULTS: Eighty players participated in the study, generating 1,656 cases eligible for analysis, of which 229 resulted in muscle injuries. The hamstrings were the most frequently injured muscle group (54%), followed by the adductor (21%), triceps surae (19%), quadriceps (5%), and psoas (1%). While CK concentration was higher in muscle injury cases [783 ± 507 U/L (95%CI, 717 to 849; min-max, 105-2,800)] compared with uninjured cases [688 ± 446 U/L (95%CI, 665 to 711; min-max, 100-2,950)], it was not an accurate predictor of subsequent muscle injury risk in professional football players (sensitivity = 56%; specificity = 55%; odds ratio = 1.00; area under curve = 0.557). CONCLUSION: CK concentration on the second post-match day cannot be used to effectively screen subsequent muscle injury risk in professional male football players.

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.

High-Intensity Intermittent Exercise Performed on the Sand Induces Higher Internal Load Demands in Soccer Players.

This study aimed to examine the acute physiological effect of shuttle-run-based high-intensity intermittent exercise (HIIE) performed at the same relative speed (i. e., 100% PST-CAR) on sand (SAND) and grass (GRASS) in male junior soccer players. Seven Under-23 Brazilian national league ("Série A") soccer players completed four testing sessions in either SAND or GRASS surface condition. The first two testing sessions consisted of performing a maximal progressive shuttle-run field protocol until volitional exhaustion (Carminatti's test, T-CAR), whereas the third and fourth sessions comprised a HIIE session on each ground surface. The HIIE session consisted of three 5-min bouts [12 s shuttle-run (with a direction change every 6 s)/12 s of passive rest] performed at 100% of T-CAR peak speed (PST-CAR) with 3 min of passive recovery between sets. Measurements of oxygen uptake (VO2), heart rate (HR), blood lactate concentration ([La]), and rating of perceived exertion (RPE) were performed during all conditions. The SAND condition elicited significantly higher %VO2peak (94.58 ± 2.73 vs. 87.45 ± 3.31%, p < 0.001, d = 2.35), %HRpeak (93.89 ± 2.63 vs. 90.31 ± 2.87%, p < 0.001, d = 1.30), RPE (8.00 ± 0.91 vs. 4.95 ± 1.23 a.u., p < 0.001, d = 2.82), and [La] (10.76 ± 2.37 vs. 5.48 ± 1.13 mmol/L, p < 0.010, d = 2.84). This study showed that higher internal workloads are experienced by the players during a single HIIE session performed on a softer surface as SAND, even when the exercise intensity was individualized based on 100%PST-CAR.

Training Loads and RSA and Aerobic Performance Changes During the Preseason in Youth Soccer Squads.

The aims of this study were to compare the internal training load (ITL) in soccer players of two competitive age groups (under-15 [U-15] and under-19 [U-19]) during an 8-week preseason training period and compare the associated changes in physical performance measures. Eighteen U-15 and twelve U-19 players were monitored over an 8-week period during the preseason phase. The ITL was monitored using the session rating of perceived exertion (RPE) method. Before and after the preseason period, physical performance was assessed by best (RSAbest) and mean (RSAmean) times in a repeated sprint ability (RSA) test and peak velocity derived from the Carminatti test (PVT-CAR). Total weekly ITL increased with age (U-15: 13770 ± 874 AU vs. U-19: 33584 ± 2506 AU; p < 0.001). In addition, U-19 players perceived training sessions as heavier than U-15 players (6.1 ± 0.3 vs. 5.3 ± 0.3 AU, respectively; p < 0.001). After the preseason period, very likely to almost certainly positive changes were observed for all performance measures in both age groups. However, the U-15 group had possibly superior gains in RSAbest (+1.40%, 90%CL -0.29 to 3.05, with ES = 0.35) and likely higher effects in RSAmean (+1.89%, 90%CL 0.04 to 3.70, with ES = 0.53) and PVT-CAR (+2.71%, 90%CL 0.35 to 5.01, with ES = 0.37) compared to the U-19 group. In conclusion, our findings demonstrate that the U-19 group accumulate higher total weekly ITLs than the U-15 group during the preseason phase due to longer and heavier training sessions. However, the U-15 group obtained superior gains in soccer-specific physical abilities while accumulating half the total ITLs during lighter training sessions.

The peak velocity of Carminatti's Test for aerobic-fitness training in male soccer players / O pico de velocidade do Teste de Carminatti para treinamento aeróbio em jogadores de futebol

Abstract Aerobic energy transference is highly required and accounts for more than 90% of total energy consumption during a soccer match. In addition high aerobic fitness contributes to recovery from high-intensity intermittent exercise, specific to performance in soccer. The aim of the present study was to examine whether the peak velocity in the Carminatti's test (PVT-CAR) for prescribing interval-training drills is effective in eliciting aerobic-fitness development intensities in male soccer-players. Fifteen Brazilian male elite soccer-players (U20) were tested for T-CAR and monitored for heart rate (HR) during PVT-CAR prescribed interval-training drills (i.e., 4x4min with 3min passive recovery). Drills were performed with a 1:1 work-to-rest ratio with either straight-line (6/6s) or 180° shuttle running (12/12s). The interval training performed at PVT-CAR elicited HR above 90% of HRmax and lactate above 4m.mol.l-1. In the shuttle-running drills, HR and lactate (93.3±2.1% HRmax; 7.7±1.4 m.mol.l-1) were significantly higher than in the straight line drills (vs 90.3±2.6 %HRmax; 4.5±0.9 m.mol.l-1). The coefficient of variations showed low inter-subject variability in HR (CV 2.3 and 3.0% for 12/12 and 6/6 respectively). The results of this study demonstrated that PVT-CAR can be successfully used to individualize high-intensity interval running training in players with different aerobic profiles, while shuttle-running drills presented higher values at intern load than straight line. The physiological and time-motion profiles resemble the most demanding phases of the match, especially for the fittest players.

Resumo A transferência de energia aeróbia é altamente necessária e representa mais de 90% do consumo total de energia durante um jogo no futebol. Ademais, a alta aptidão aeróbia contribui para a recuperação durante exercício intermitente de alta intensidade, específico do desempenho do futebol. O objetivo deste estudo foi examinar se o pico de velocidade no teste de Carminatti (PVT-CAR) para a prescrição de treino intervalado é funcional na obtenção de desenvolvimento de aptidão aeróbia em jogadores de futebol. Quinze jogadores de futebol brasileiros (Sub-20) foram testados no T-CAR e monitorados por freqüência cardíaca (FC) durante o treinamento intervalado prescrito por PVT-CAR (ou seja, 4x4min com recuperação passiva de 3min). Os treinos foram realizados com uma relação de trabalho e repouso de 1:1 com corrida em linha reta (6/6s) e corrida de 180° com mudança de direção em vai-e-vem (12/12s). O treinamento intervalado prescrito com PVT-CAR induziu respostas de FC acima de 90% de FCmax, lactato superior a 4m.mol.l-1. uOs resultados de FC e lactato no treinamento de corrida com mudança de direção (93,3±2,1% FCmax; 7,7±1,4 m.mol.l-1) foram significativamente maiores que no treino de corrida em linha (vs 90,3±2,6 %FCmax; 4,5±0,9 m.mol.l-1). O coeficiente de variação mostrou baixa variabilidade inter-sujeitos na frequência cardíaca (CV 2,3 e 3,0% para 12/12 e 6/6, respectivamente). Os resultados do estudo mostraram que o PVT-CAR pode ser utilizado com sucesso para individualizar o treinamento de corrida intervalado de alta intensidade em jogadores com diferentes perfis aeróbicos. Os perfis fisiológicos e momentos de demandas se assemelham às fases mais exigentes da partida, especialmente para os jogadores melhor condicionados.

Potência aeróbia em atletas de futebol e futsal de diferentes níveis competitivos / Aerobic power in soccer and futsal players of different competitive levels

O objetivo do presente estudo foi comparar os valores de potência e capacidade aeróbia entre atletas de futebol e futsal nos diferentes níveis competitivos e modalidades. A amostra foi constituída de 116 atletas do sexo masculino de seis equipes (3 de futebol e 3 de futsal) da 1ª divisão, 2ª divisão e universitário. Os participantes foram submetidos a duas sessões de coleta de dados. Na primeira sessão, uma avaliação antropométrica foi conduzida e familiarização com o teste de Carminatti (T-CAR). Na segunda sessão, foi realizado o teste de T-CAR de corrida intermitente, para determinar o pico de velocidade (PV). Para analisar as diferenças entre os valores médios dos dados antropométricos e fisiológicos das equipes e nos diferentes níveis competitivos foi utilizado ANOVA One-Way seguido do teste de Post-Hoc de Bonferroni. O Teste T para amostras independentes foi utilizado para comparar as médias entre as modalidades. O valor de P < 0,05 foi considerado como nível de significância estatística. Maiores níveis de PVT-CAR e 80,4%PVT-CAR foram reportados nos atletas de futebol da 1ª divisão comparado com o da 2ª divisão do futsal e universitários, e entre as equipes da 1ª divisão de futsal e 2ª do futebol comparado com o futsal universitário. Além disso, maiores valores do PVT-CAR nas equipes da 1ª divisão de futsal e 2ª do futebol comparado com universitários e nos atletas de futebol versus futsal (p<0,05), afirmando que existe diferença entre os níveis competitivos e modalidades. Estes resultados sugerem que atletas de futebol e aqueles que atuam em elevados níveis competitivos possuem melhor condição física no desempenho do T-CAR....(AU)

The aim of this study was to compare the power levels and aerobic capacity between soccer and futsal players on different competitive levels and modalities. One hundred and sixteen male players from three soccer and futsal teams of the 1st division, 2nd division and university participated in the study. The participants underwent two data collection sessions. In the first session, an anthropometric assessment and familiarization with Carminatti's test (T-CAR) was conducted. In the second session, the T-CAR intermittent running test was conducted to determine the peak velocity (PV). One-way ANOVA was used in combination with post hoc testing (Bonferroni) to compare the average values of anthropometric and physiological data of the teams and in different competitive levels. The T test for independent samples was used to compare the means of the modality. Significance was assumed at 5% (P < 0.05). Aerobic indices were obtained by T-CAR. Higher levels of PVT-CAR and 80,4%PVT-CAR were reported on soccer players of st division compared to the futsal of 2nd division and university, and between the teams of the 1st futsal division and 2nd soccer division compared to the university futsal. In addition, higher PVT-CAR values on teams of 1st futsal division and 2nd soccer division compared to university and soccer players versus futsal (P < 0.05), declaring that there is a difference between the competitive levels and modalities. These results suggest that soccer players and those that play at high competitive levels have better performance in TCAR....(AU)

The effect of two generic aerobic interval training methods on laboratory and field test performance in soccer players.

The purpose of this study was to compare the effects of 2 generic aerobic training models, based on peak running velocity in Carminatti's test (PVT-CAR) in U-20 elite soccer players. Seventeen soccer players (age: 17.9 ± 1.0 years; 178.6 ± 5.0 cm; 73.6 ± 6.6 kg; 11.1 ± 1.3%) from a team competing in a national junior league took part in the study. The athletes performed a series of pre- and posttraining tests (incremental test on a treadmill to determine the maximal oxygen uptake [(Equation is included in full-text article.)], velocity at maximal oxygen uptake [(Equation is included in full-text article.)], the lactate threshold [LT], and T-CAR). The interval training models applied were with 180° direction change (T12:12; n = 9) and without direction change (T6:6; n = 8). No significant interaction (time vs. group) was observed for the majority of variables analyzed (p > 0.05), although significant main effects in time were evident regarding peak treadmill velocity (PVTREAD) (F = 56.3, p < 0.0001), (Equation is included in full-text article.)(F = 35.8, p < 0.0001), LT (F = 57.7, p < 0.0001), and PVT-CAR (F = 52.9, p < 0.0001). Moreover, there was no significant change in (Equation is included in full-text article.)between pre and posttraining period (F = 4.26, p = 0.056) in both training groups. Thus, it can be concluded that the prescribed training with and without direction change in the intensity of the PVT-CAR increases the PVTREAD, the (Equation is included in full-text article.), the LT, and the PVT-CAR similarly.

Somatotype of competitive youth soccer players from Brazil.

The aim of this study was to identify the morphological configuration of youth athletes from professional soccer clubs and to verify their differences according to the tactical position on the field. Overall, 67 male players aged 15 to 17 years were evaluated. The examined anthropometric measurements included body mass, body height, skinfolds (triceps, subscapular, supraspinal and medial calf), girths (flexed and tensed arm and calf) and breadths (humerus and femur). For statistical purposes, analysis of variance and post hoc Bonferroni and Kruskal-Wallis tests were used. We concluded that goalkeepers were heavier and taller than center backs (p = 0.015 and p = 0.001), midfielders (p = 0.005 and p <0.001) and center forward players (p = 0.024 and p <0.001). The average somatotype for defense, forward and goalkeeper positions was a balanced mesomorph. Midfield players showed ectomorphic-mesomorph characteristics. It was concluded that goalkeepers were characterized as being taller and heavier and that somatotype features of athletes were similar between positions, except for midfield players.

Perfil antropométrico e performance aeróbia e anaeróbia em jovens jogadores de futebol / Anthropometric profile and aerobic and anaerobic performance in young soccer players

O objetivo do presente estudo foi comparar as características antropométricas e performance aeróbia e anaeróbia de adolescentes jogadores de futebol. Para tanto, participaram deste estudo 34 jogadores da categoria infantil (INF) (idade 14,44 ± 0,55 anos, massa corporal 60,94 ± 8,51 kg, estatura 173,16 ± 8,91 cm) e 30 jogadores da categoria juvenil (JUV) (idade: 15,94 ± 0,69 anos, massa corporal 70,0 ± 9,86 kg, estatura 177,58 ± 8,24 cm).Todos os adolescentes foram submetidos a medidas antropométricas, composição corporal e somatotipo, seguido pelos seguintes protocolos de campo: teste de Carminatti (T-CAR) para avaliação da potência aeróbia máxima a partir da determinação do pico de velocidade (PV), teste anaeróbio de sprints repetidos e teste de velocidade de 10 e 30 m. Para detectar possíveis diferenças entre as categorias competitivas foi utilizado o teste t de Student para amostras independentes adotando o nível de significância de 5%. Os jogadores JUV foram mais pesados, mais altos e apresentaram maiores perímetros musculares comparado aos jogadores INF, enquanto para o somatório das dobras cutâneas não foram visualizadas diferenças. Os desempenhos nos testes aeróbios e anaeróbios analisados foram significativamente superiores para a categoria juvenil em relação à infantil. Dessa forma, podemos concluir que a idade cronológica determina as diferenças nas características antropométricas e nos desempenhos físico de jovens jogadores no meio (categoria infantil) e final (categoria juvenil) da adolescência como provável resultado do processo de crescimento e maturação biológica.

The aim of this study was to compare anthropometric characteristics and aerobic and anaerobic performance of adolescent soccer players. For this, young soccer players classified asunder 15 - U15 (n=34; age 14.44 ± 0.55 years, body mass 60,94 ± 8,51 kg, stature 173,16 ± 8,91 cm) and under 17 - U17 (n=30; age 15.94 ± 0.69 years, body mass 70,0 ± 9,86 kg, stature 177,58 ± 8,24 cm) participated in this study. All adolescents were submitted to performed anthropometric assessments, body composition andsomatotype, accompanied by the following field tests protocols: Carminatti test (T-CAR) for the evaluation of maximal aerobic power from the determination of the peak velocity (PV), repeated sprints anaerobic test (40 m RSA) and the 10 m and 30 m speed test. To detect possible differences between competitive age groups (U-17 vs. U-15) was used t test for independent samples adopting significance level of 5%. Older players (U-17) were heavier, taller and had greater muscle circumferences compared to youngest players belonging U-15 age group, while for the sum of skinfolds were not visualized differences among them. Thus, we can conclude that chronological age determines differences in morphological characteristics and motor performances (aerobic and anaerobic indicators) of young soccer players in middle (U-15) and end (U-17) of adolescence period as probable outcome of biological growth and development.

Comparação da potência anaeróbia entre as posições táticas em jogadores de futebol: estudo retrospectivo / Comparison of anaerobic power between tactical positions in soccer players: a retrospective study

O objetivo do estudo foi comparar a Potência anaeróbia máxima (Pmáx); Potência Anaeróbia Média (Pmed) e índice de fadiga (IF) entre atletas de diferentes posições táticas no futebol. Para isso, 248 atletas profissionais de futebol de campo (25,8±1,72 anos, 77,52±4,90 Kg e 178,48±5,63 cm), pertencentes a 1ª e 2ª divisão do estado do Rio Grande do Sul, avaliados durante o período de 1999-2010, divididos em cinco posições táticas: goleiros (GO) (n=28), laterais (LA) (n=35), zagueiros (ZA) (n=54), meio-campistas (MC) (n=81) e atacantes (AT) (n=50). Os atletas executaram o RAST test para determinar a Pmáx, Pmed e IF. Foi utilizada a ANOVA one way e post hoc de Tukey adotando-se o valor de significância de p<0,05. Diferenças significativas para a Pmáx (p<0,05) dos LA comparadas aos GO, ZA e MC; da Pmed dos LA para os GO, ZA e MC e dos AT e MC em relação aos GO (p<0,05). Na potência relativa de cada sprint, houve manutenção durante o 1º e 2º sprint entre as posições, exceto os MC e durante o 5º e 6º sprint, independente da posição, não houve decréscimo do desempenho de potência. Visto que foram encontradas diferenças significativas de Pmáx e da Pmed, dos LA em relação aos GO, ZA e MC, concluímos que esta evidência confirma que atletas de diferentes posições táticas apresentam variação quanto às características de suas ações.

This study aimed to compare the maximal anaerobic power (Pmáx), mean anaerobic power (Pm) and fatigue index (FI) among soccer players of different tactical positions. For this purpose, 248 professional soccer players (25.8±1.72 years old, 77.52±4.90 kg and 178.48±5.63 cm) from the 1st and 2nd division of the Rio Grande do Sul State, Brazil, participated in this study. They were evaluated between 1999 and 2010 and divided into five positions: goalkeepers (GK) (n=28), external defenders (ED) (n=35), central defenders (CD) (n=54), midfielders (MF) (n=81), and forwards (F) (n=50). The RAST test was performed to evaluate their Pmáx, Pmed, and FI. ANOVA one-way and Tukey's post hoc were used to evaluate the relationship between the variables; significant level was p<0.05. Significant differences (p<0.05) were found for Pmáx of ED compared to GK, CD and MF. Similarly, Pm of ED also presented significant difference when compared to GK, CD and MF, as well as of F and MF compared to GK (p<0.05). In the relative power of each sprint, the athletes maintained the velocity during the 1st and 2nd sprint regardless of their positions, except for MF, and during the 5th and 6th sprint. There was no decrease in power performance for all positions. Since significant differences were found in Pmáx and Pm of ED compared to GK, CD and MF, we conclude that athletes of different tactical positions presented variation regarding the characteristics of their actions.

Análise da potência muscular de atletas de futebol da categoria juniores em diferentes momentos da temporada de competição / Assessment of muscle power of soccer athletes of junior category at different moments of the season competition

O objetivo deste estudo foi comparar a potência muscular de membros inferiores a partir do counter movement jump (CMJ) em diferentes momentos da temporada (final da temporada, inicio e final da pré-temporada seguinte) em jogadores de futebol e, além disso, foram estudados dados de composição corporal nos três momentos analisados. Participaram do estudo 17 atletas de futebol com idade de 17,8 ± 1,1 anos da categoria juniores de um clube de futebol profissional participante da série A do Campeonato Brasileiro. O percentual de gordura corporal estimado no início da pré-temporada foi significativamente superior ao mensurado no final da temporada anterior (p<0,05). O desempenho no salto vertical apresentou uma queda significativa (5,8%, p<0,05) apenas após a realização da pré-temporada quando analisada a variável altura. Por outro lado, a potência muscular normalizada pelo peso corporal apresentou manutenção nos três momentos analisados, indicando que o desempenho no CMJ é uma variável que não apresenta alteração após um período curto (4 semanas) sem treinamento formal e que a maior ênfase no treinamento aeróbio na pré-temporada pode ter contribuído para reduzir os níveis de potência muscular e a altura atingida num salto vertical.

The aim of this study was to compare the muscle power of the lower limbs by measuring the counter movement jump (CMJ) of soccer players at different moments of the season (end of the season, beginning and end of the next preseason). Body composition data were also collected at the three moments analyzed. Seventeen junior soccer players aged 17.8 ± 1.1 years from a professional football club participating in the Brazilian Championship volunteered to take part in this study. The % of body fat at the beginning of the preseason was significantly higher than that measured at the end of the previous season (p<0.05). Vertical jump height declined significantly (5.8%, p<0.05) after the completion of the preseason. On the other hand, muscle power was maintained at the three moments when normalized for body mass, suggesting that CMJ performance presents no modification after a short period (4 weeks) without formal training. Further, the large emphasis on aerobic training during preseason may have contributed to the lower levels of muscle power and jump height.

Diferença entre intensidade do exercício prescritapor meio do teste TCAR no solo arenoso e na grama / Prescribed differences in exercise intensity based on the TCARtest over sandy ground and grass

The intensity of training might be influenced by exercise mode and type of terrain. Thus, the objective of this study was a) to compare the physiological indices determined in the TCAR test carried out on natural grass (NG) and sandy ground (SG), and b) to analyze heart rate (HR) and blood lactate responses during constant exercise on SG and NG. Ten soccer players (15.11 ± 1.1 years, 168 ± 4.0 cm, 60 ± 4.0 kg) were submitted to the TCAR test to determine peak velocity (PV) and the intensity corresponding to 80.4% PV (V80.4) on NG and SG. The second evaluation consisted of two constant load tests (CLT) (80.4% PV on NG and SG) with a duration of 27 min. The paired Student t-test was used to compare the tests carried out on NG and SG. ANOVA (two-way), complemented by the Tukey test, was used to compare lactate concentrations [La] at 9, 18 and 27 min between the two types of terrain. A p value <0.05 was adopted. PV and V80.4 (15.3±1.0 and 12.3±0.6 km/h) were significantly higher on grass than on sand (14.3±1.0 and 11.5±0.4 km/h). Lactate concentration during the CLT [LaV80.4] was significantly higher on sand (4.1±0.9 mmol/L) than on grass (2.8±0.7 mmol/L). In the CLT, no significant difference in mean HR was observed between the two terrains, whereas there was a difference in [La]. In conclusion, the type of terrain interferes with indicators associated with aerobic power and capacity obtained by the TCAR test.

The intensity of training might be influenced by exercise mode and type of terrain. Thus, the objective of this study was a) to compare the physiological indices determined in the TCAR test carried out on natural grass (NG) and sandy ground (SG), and b) to analyze heart rate (HR) and blood lactate responses during constant exercise on SG and NG. Ten soccer players (15.11 ± 1.1 years, 168 ± 4.0 cm, 60 ± 4.0 kg) were submitted to the TCAR test to determine peak velocity (PV) and the intensity corresponding to 80.4% PV (V80.4) on NG and SG. The second evaluation consisted of two constant load tests (CLT) (80.4% PV on NG and SG) with a duration of 27 min. The paired Student t-test was used to compare the tests carried out on NG and SG. ANOVA (two-way), complemented by the Tukey test, was used to compare lactate concentrations [La] at 9, 18 and 27 min between the two types of terrain. A p value <0.05 was adopted. PV and V80.4 (15.3±1.0 and 12.3±0.6 km/h) were significantly higher on grass than on sand (14.3±1.0 and 11.5±0.4 km/h). Lactate concentration during the CLT [LaV80.4] was significantly higher on sand (4.1±0.9 mmol/L) than on grass (2.8±0.7 mmol/L). In the CLT, no significant difference in mean HR was observed between the two terrains, whereas there was a difference in [La]. In conclusion, the type of terrain interferes with indicators associated with aerobic power and capacity obtained by the TCAR test.