Previous studies have associated angiotensin-converting enzyme (ACE) D allele with variability in the skeletal muscle baseline strength, though conclusions have been inconsistent across investigations. The purpose of this study was to examine the possible association between ACE genotype and skeletal muscle baseline strength in elite male and female athletes involved in different event expertise. A group of 58 elite athletes, designated as Olympic candidates, were studied: 35 swimmers (19 males and 16 females, 18.8 ± 3.2 years) and 23 triathletes (15 males and 8 females, 18.7 ± 3.0 years). The athletes were classified as: short (≤ 200m) and middle (400m to 1500m) distance athletes, respectively. For each subject the grip strength in both hands was measure using an adjustable mechanical hand dynamometer. The maximum height in both squat jump (SJ) and counter movement jump (CMJ) were also assessed, using a trigonometric carpet (Ergojump Digitime 1000; Digitest, Jyvaskyla, Finland). DNA extraction was obtained with Chelex 100® and genotype determination by PCR-RFLP methods. Both males and females showed significantly higher right grip strength in D allele carriers compared to II homozygote’s. We found that allelic frequency differs significantly by event distance specialization in both genders (p < 0.05). In fact, sprinter D allele carriers showed the superior scores in nearly all strength measurements (p < 0.05), in both genders. Among endurance athletes, the results also demonstrated that female D allele carriers exhibited the higher performance right grip and CMJ scores (p < 0.05). In conclusion, the ACE D allele seems associated with skeletal muscle baseline strength in elite athletes, being easily identified in females.

The aims of the present study were to assess critical velocity using the swimmer curriculum in front crawl events and to compare critical velocity to the velocity corresponding to a 4 mmol·l-1 of blood lactate concentration and to the velocity of a 30 min test. The sample included 24 high level male swimmers ranged between 14 and 16 years old. For each subject the critical velocity, the velocity corresponding to a 4 mmol·l-1 of blood lactate concentration and the mean velocity of a 30 min test were determined. The critical velocity was also estimated by considering the best performance of a swimmer over several distances based on the swimmer curriculum. Critical velocity including 100, 200 and 400 m events was not different from the velocity of 4 mmol·l-1 of blood lactate concentration. Critical velocity including all the swimmer events was not different from the velocity of a 30 min test. The assessment of critical velocity based upon the swimmer curriculum would therefore seem to be a good approach to determine the aerobic ability of a swimmer. The selection of the events to be included in critical velocity assessment must be a main concern in the evaluation of the swimmer.

Several studies claim that the physical effort of students during the Physical Education classes (PE) is low. There is a lack of desirable intensity to cause adaptations and improvement of physical fitness. Purpose: In this study, we intend to analyse the average values of heart rate (HR) during different phases of the PE class, trying to identify possible differences between collective and individual sports (basketball and apparatus gymnastics). The sample consisted of a group of 15 students, 5 female and 10 male (15.2 ± 12:56 years) and the study was conducted over 10 sessions (5 of each type), registering values of HR (bpm) using HR monitors (Polar Electronic, FT1 model). Results: After exploratory data analysis there were significant differences in the transition phase (basketball: 146 ± 27.2 bpm, p = 0.001; apparatus gymnastics: 138.4 ± 25.8 bpm, p = 0.001) and the drilling stage (basketball: 151.2 ± 26.1 bpm, p = 0.000; gymnastics apparatus: 143.0 ± 27.0 bpm, p = 0.000). In the process of organizing, the differences were not significant (basketball: 136.8 ± 26.2 bpm, p = 0526; apparatus gymnastics: 132.3 ± 23.9 bpm, p = 0526). Conclusions: Having these results, we believe that PE teachers should plan sessions that provide increased uptime and higher levels of intensity for students, especially in periods of drilling, regardless of the class.

Aim: The purpose of this study was to analyze secular trends in anthropometrics and physical fitness of Portuguese children. Methods: 1819 students (881 boys and 938 girls) between 10 and 11 years old, were assessed in their 5th and 6th scholar grade throughout a 20 years’ time-frame. ANCOVA models were used to analyze variations in anthropometrics (height, weight and body mass index) and physical fitness (sit and reach, sit ups, horizontal jump and sprint time) across four quinquennials (1993-1998; 1998-2003; 2003-2008; 2008-2013). Results: Secular trends showed the presence of heavier boys and girls with higher BMI in the 5th and 6th grade throughout the last 20 years. There was also a presence of taller girls but just until the 3rd quinquennial. Both boys and girls were able to perform better on the core strength test and sprint time but become less flexible over the years. Mean jumping performance remained unchanged for both genders. Conclusions: Our results indicate the presence of positive secular trends in BMI and in some physical fitness components (strength and speed) among the Portuguese youth.

De entre as técnicas não invasivas de determinação do limiar anaeróbio, o método da determinação da velocidade crítica tem merecido grande atenção, nomeadamente no âmbito da avaliação e controlo do treino em natação. Neste sentido, o objetivo do presente artigo foi efetuar uma revisão da literatura do tipo qualitativa acerca do significado do parâmetro velocidade crítica e sua aplicação à natação. Foram abordadas questões relativas à origem e definição do conceito de velocidade crítica, às metodologias de determinação mais comuns, bem como uma breve referência ao conceito de velocidade crítica anaeróbia. A velocidade crítica é sugerida como um parâmetro não invasivo de avaliação do desempenho aeróbio e de predição do limiar anaeróbio de nadadores, independentemente do nível desportivo. As principais vantagens deste indicador resultam da facilidade de aplicação e análise num elevado número de nadadores, sem a necessidade da utilização de equipamentos dispendiosos ou de recolha de sangue. Aponta-se como uma ferramenta útil no mecanismo de prescrição e controlo de cargas de treino por meio de resultados em condições experimentais ou recorrendo a tempos obtidos durante as competições. A descriminação dos valores de velocidade crítica entre nadadores com diferentes perfis metabólicos (velocistas versus fundistas) e ainda a sua aplicabilidade em regime anaeróbio são aspetos que ainda carecem de um maior entendimento.

Introduction: The main purpose of this study was to have a comparison of the physical fitness levels and body mass index of students with urban and rural residence from an elementary school in Portugal. Methods: The sample covered 270 students, 142 male and 128 female, aged between 9 and 16, from the 5th to the 9th grade. The Fitnessgram test battery (NES, 2002) measured the physical fitness, the body mass index was based on the reference values from the World Health Organization (1995) and the students' characterization was assessed through the biographical archives given by the school. Results: The test results only demonstrated significant differences (p <0.05) amongst these students: Females in the 5th and 6th grade in the following tests, trunk extension with better results in students with rural residence and middle strenght with better results in students with urban residence; Males in the 5th and 6th grade in the following tests: the shuttle run with better results in students with rural residence; Females between 7th and 9th grade in the following tests: trunk extension with better results in students with urban residence. Conclusions: Significant differences were not observed between the levels of physical fitness and BMI related to the place of residence (rural and urban).

O objetivo central do artigo foi analisar as perceções dos nadadores Portugueses sobre o seu contexto de desenvolvimento desportivo. Foram estudadas as perceções de 207 nadadores Portugueses de nível nacional (juniores e séniores), homens e mulheres, provenientes de 28 clubes de natação. Os nadadores foram diferenciados em três grupos de acordo com o nível desportivo médio do clube. Foi aplicada uma versão adaptada do Talent Development Environment Questionnaire for Sport (TDEQ), o qual, estatisticamente, demonstrou uma confiabilidade excelente (> .8) ou satisfatória (> .6) em cinco dos sete fatores. Contudo as comunalidades associadas a cada variável apresentam bastante variabilidade (entre 0.04 e 0.768). Quanto às perceções dos nadadores inquiridos, os dados sugerem que a qualidade do contexto de desenvolvimento desportivo não parece ser significativamente distinto entre os 28 clubes de natação Portugueses envolvidos em divisões desportivas distintas.

The aims of the present study were to assess critical velocity using the swimmer curriculum in front crawl events and to compare critical velocity to the velocity corresponding to a 4 mmol·l(-1) of blood lactate concentration and to the velocity of a 30 min test. The sample included 24 high level male swimmers ranged between 14 and 16 years old. For each subject the critical velocity, the velocity corresponding to a 4 mmol·l(-1) of blood lactate concentration and the mean velocity of a 30 min test were determined. The critical velocity was also estimated by considering the best performance of a swimmer over several distances based on the swimmer curriculum. Critical velocity including 100, 200 and 400 m events was not different from the velocity of 4 mmol·l(-1) of blood lactate concentration. Critical velocity including all the swimmer events was not different from the velocity of a 30 min test. The assessment of critical velocity based upon the swimmer curriculum would therefore seem to be a good approach to determine the aerobic ability of a swimmer. The selection of the events to be included in critical velocity assessment must be a main concern in the evaluation of the swimmer. Key pointsCritical velocity using 100, 200 and 400 m events was not different from the velocity of 4 mmol·l(-1) of blood lactate concentration.Critical velocity using all the swimmer events was not different from the velocity of a 30 min test.The assessment of critical velocity based upon the swimmer curriculum seemed to be a good approach to determine the aerobic capacity of a swimmer.The decision on the events to be analysed must be a main concern in the evaluation of the swimmer critical velocity.

Previous studies have associated angiotensin-converting enzyme (ACE) D allele with variability in the skeletal muscle baseline strength, though conclusions have been inconsistent across investigations. The purpose of this study was to examine the possible association between ACE genotype and skeletal muscle baseline strength in elite male and female athletes involved in different event expertise. A group of 58 elite athletes, designated as Olympic candidates, were studied: 35 swimmers (19 males and 16 females, 18.8 ± 3.2 years) and 23 triathletes (15 males and 8 females, 18.7 ± 3.0 years). The athletes were classified as: short (≤ 200m) and middle (400m to 1500m) distance athletes, respectively. For each subject the grip strength in both hands was measure using an adjustable mechanical hand dynamometer. The maximum height in both squat jump (SJ) and counter movement jump (CMJ) were also assessed, using a trigonometric carpet (Ergojump Digitime 1000; Digitest, Jyvaskyla, Finland). DNA extraction was obtained with Chelex 100(®) and genotype determination by PCR-RFLP methods. Both males and females showed significantly higher right grip strength in D allele carriers compared to II homozygote's. We found that allelic frequency differs significantly by event distance specialization in both genders (p < 0.05). In fact, sprinter D allele carriers showed the superior scores in nearly all strength measurements (p < 0.05), in both genders. Among endurance athletes, the results also demonstrated that female D allele carriers exhibited the higher performance right grip and CMJ scores (p < 0.05). In conclusion, the ACE D allele seems associated with skeletal muscle baseline strength in elite athletes, being easily identified in females. Key pointsDD homozygote's and D allele carriers from both genders shows significantly higher right grip strength.Right grip strength remains significantly higher in the D allele carrier's female endurance group.Female's D allele carriers exhibited the higher performance counter-movement jump scores.ACE genotype effects in skeletal-muscle strength are diverse by gender, being easily identified in females.

Introduction: The purpose of this study was to analyze secular trends in anthropometrics and physical fitness of Portuguese children. Material and Methods: A group of 1819 students (881 boys and 938 girls) between 10 and 11 years old was assessed in their 5th and 6th scholar grade throughout a 20 years’ time-frame. ANCOVA models were used to analyze variations in anthropometrics (height, weight and body mass index) and physical fitness (sit and reach, curl-up, horizontal jump and sprint time) across four quinquennials (1993 - 1998; 1998 - 2003; 2003 - 2008; 2008 - 2013). Results: Secular trends showed the presence of heavier boys and girls with higher body mass index in the 5th and 6th grade throughout the last 20 years. There was also a presence of taller girls but just until the 3rd quinquennial. Both boys and girls were able to perform better on the core strength test and sprint time but become less flexible over the years. Mean jumping performance remained unchanged for both genders. Discussion: The present study provides novel data on anthropometrics and physical fitness trends over the last two decades in young Portuguese children, consistent with the results reported in other developed countries. Conclusion: Evidence for the start of a positive secular trend in body mass index and in some physical fitness components over the last two decades among the Portuguese youth.